1. |
- Anesater, Erik, et al.
(författare)
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A Rigid Disc for Protection of Exposed Blood Vessels During Negative Pressure Wound Therapy
- 2013
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Ingår i: Surgical Innovation. - : SAGE Publications. - 1553-3506 .- 1553-3514. ; 20:1, s. 74-80
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Tidskriftsartikel (refereegranskat)abstract
- Background. There are increasing reports of serious complications and deaths associated with negative pressure wound therapy (NPWT). Bleeding may occur when NPWT is applied to a wound with exposed blood vessels. Inserting a rigid disc in the wound may protect these structures. The authors examined the effects of rigid discs on wound bed tissue pressure and blood flow through a large blood vessel in the wound bed during NPWT. Methods. Wounds were created over the femoral artery in the groin of 8 pigs. Rigid discs were inserted. Wound bed pressures and arterial blood flow were measured during NPWT. Results. Pressure transduction to the wound bed was similar for control wounds and wounds with discs. Blood flow through the femoral artery decreased in control wounds. When a disc was inserted, the blood flow was restored. Conclusions. NPWT causes hypoperfusion in the wound bed tissue, presumably as a result of mechanical deformation. The insertion of a rigid barrier alleviates this effect and restores blood flow.
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2. |
- Anesäter, Erik, et al.
(författare)
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The influence on wound contraction and fluid evacuation of a rigid disc inserted to protect exposed organs during negative pressure wound therapy.
- 2011
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Ingår i: International Wound Journal. - 1742-481X. ; 8, s. 393-399
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Tidskriftsartikel (refereegranskat)abstract
- The use of a rigid disc as a barrier between the wound bed and the wound filler during negative pressure wound therapy (NPWT) has been suggested to prevent damage to exposed organs. However, it is important to determine that the effects of NPWT, such as wound contraction and fluid removal, are maintained during treatment despite the use of a barrier. This study was performed to examine the effect of NPWT on wound contraction and fluid evacuation in the presence of a rigid disc. Peripheral wounds were created on the backs of eight pigs. The wounds were filled with foam, and rigid discs of different designs were inserted between the wound bed and the foam. Wound contraction and fluid evacuation were measured after application of continuous NPWT at -80 mmHg. Wound contraction was similar in the presence and the absence of a rigid disc (84 ± 4% and 83 ± 3%, respectively, compared with baseline). Furthermore, the rigid disc did not affect wound fluid removal compared with ordinary NPWT (e.g. after 120 seconds, 71 ± 4 ml was removed in the presence and 73 ± 3 ml was removed in the absence of a disc). This study shows that a rigid barrier may be placed under the wound filler to protect exposed structures during NPWT without affecting wound contraction and fluid removal, which are two crucial features of NPWT.
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3. |
- Anesäter, Erik, et al.
(författare)
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The use of a rigid disc to protect exposed structures in wounds treated with negative pressure wound therapy: Effects on wound bed pressure and microvascular blood flow.
- 2012
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Ingår i: Wound Repair and Regeneration. - 1524-475X. ; 20:4, s. 611-616
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Tidskriftsartikel (refereegranskat)abstract
- There are increasing reports of deaths and serious complications associated with the use of negative pressure wound therapy (NPWT). Bleeding may occur in patients when NPWT is applied to a wound with exposed blood vessels or vascular grafts, possibly due to mechanical deformation and hypoperfusion of the vessel walls. Recent evidence suggests that using a rigid barrier disc to protect underlying tissue can prevent this mechanical deformation. The aim of this study was to examine the effect of rigid discs on the tissue exposed to negative pressure with regard to tissue pressure and microvascular blood flow. Peripheral wounds were created on the backs of eight pigs. The pressure and microvascular blood flow in the wound bed were measured when NPWT was applied. The wound was filled with foam, and rigid discs of different designs were inserted between the wound bed and the foam. The discs were created with or without channels (to accommodate exposed sensitive structures such as blood vessels and nerves), perforations, or a porous dressing that covered the underside of the discs (to facilitate pressure transduction and fluid evacuation). When comparing the results for pressure transduction to the wound bed, no significant differences were found using different discs covered with dressing, whereas pressure transduction was lower with bare discs. Microvascular blood flow in the wound bed decreased by 49 ± 7% when NPWT was applied to control wounds. The reduction in blood flow was less in the presence of a protective disc (e.g., -6 ± 5% for a dressing-covered, perforated disc, p = 0.006). In conclusion, NPWT causes hypoperfusion of superficial tissue in the wound bed. The insertion of a rigid barrier counteracts this effect. The placement of a rigid disc over exposed blood vessels or nerves may protect these structures from rupture and damage.
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4. |
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5. |
- Dohmen, Pascal M, et al.
(författare)
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Use of incisional negative pressure wound therapy on closed median sternal incisions after cardiothoracic surgery: clinical evidence and consensus recommendations.
- 2014
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Ingår i: Medical Science Monitor. - 1643-3750. ; 20, s. 1814-1825
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Negative pressure wound therapy is a concept introduced initially to assist in the treatment of chronic open wounds. Recently, there has been growing interest in using the technique on closed incisions after surgery to prevent potentially severe surgical site infections and other wound complications in high-risk patients. Negative pressure wound therapy uses a negative pressure unit and specific dressings that help to hold the incision edges together, redistribute lateral tension, reduce edema, stimulate perfusion, and protect the surgical site from external infectious sources. Randomized, controlled studies of negative pressure wound therapy for closed incisions in orthopedic settings (which also is a clean surgical procedure in absence of an open fracture) have shown the technology can reduce the risk of wound infection, wound dehiscence, and seroma, and there is accumulating evidence that it also improves wound outcomes after cardiothoracic surgery. Identifying at-risk individuals for whom prophylactic use of negative pressure wound therapy would be most cost-effective remains a challenge; however, several risk-stratification systems have been proposed and should be evaluated more fully. The recent availability of a single-use, closed incision management system offers surgeons a convenient and practical means of delivering negative pressure wound therapy to their high-risk patients, with excellent wound outcomes reported to date. Although larger, randomized, controlled studies will help to clarify the precise role and benefits of such a system in cardiothoracic surgery, limited initial evidence from clinical studies and from the authors' own experiences appears promising. In light of the growing interest in this technology among cardiothoracic surgeons, a consensus meeting, which was attended by a group of international experts, was held to review existing evidence for negative pressure wound therapy in the prevention of wound complications after surgery and to provide recommendations on the optimal use of negative pressure wound therapy on closed median sternal incisions after cardiothoracic surgery.
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6. |
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7. |
- Haraldsen, Pernille, et al.
(författare)
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A porcine model for acute ischaemic right ventricular dysfunction.
- 2014
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Ingår i: Interactive Cardiovascular and Thoracic Surgery. - : Oxford University Press (OUP). - 1569-9285 .- 1569-9293. ; 18:1, s. 43-48
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Tidskriftsartikel (refereegranskat)abstract
- To establish an experimental model for acute ischaemic isolated right ventricular dysfunction and the subsequent haemodynamic changes.
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8. |
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9. |
- Ingemansson, Richard, et al.
(författare)
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A protective device for negative-pressure therapy in patients with mediastinitis.
- 2013
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Ingår i: Annals of Thoracic Surgery. - : Elsevier BV. - 1552-6259 .- 0003-4975. ; 95:1, s. 362-364
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Tidskriftsartikel (refereegranskat)abstract
- A devastating complication associated with negative-pressure wound therapy (NPWT) after cardiac surgical intervention is heart rupture resulting in serious bleeding. The benefit of a rigid barrier between the underlying organs and the sharp sternal edges has been demonstrated in pigs. In the present article, we present our first 6 patients with deep sternal wound infection treated with NPWT in combination with a protective device. The median duration of NPWT was 8 days (range, 6-14 days). No major bleeding or signs of organ damage were observed. The use of a protective device seems to decrease the risk of bleeding complications.
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10. |
- Ingemansson, Richard, et al.
(författare)
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Clinical transplantation of initially rejected donor lungs after reconditioning ex vivo.
- 2009
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Ingår i: Annals of Thoracic Surgery. - : Elsevier BV. - 1552-6259 .- 0003-4975. ; 87:1, s. 255-260
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: A major problem in clinical lung transplantation is the shortage of donor lungs. Only about 20% of donor lungs are accepted for transplantation. A method to evaluate and recondition lungs ex vivo has been tested on donor lungs that have been rejected for transplantation. METHODS: The donor lungs were reconditioned ex vivo in an extracorporeal membrane oxygenation (ECMO) circuit with STEEN solution (Vitrolife AB, Kungsbacka, Sweden) mixed with erythrocytes. The hyperoncotic solution dehydrates edematous lung tissue. Functional evaluations were performed with deoxygenated perfusate by varying the inspired fraction of oxygen. After the reconditioning, the lungs were kept immersed at 8 degrees C in extracorporeal membrane oxygenation until transplantation was performed. RESULTS: Six of nine initially rejected donor lungs were reconditioned to acceptable function, and in six recipients, double lung transplantation was performed. Three-month survival was 100%. One patient has since died due to sepsis after 95 days, and one due to rejection after 9 months. Four recipients are alive and well without any sign of bronchiolitis obliterans syndrome 24 months after the transplantation. CONCLUSIONS: The result from the present study is promising, and we continue to transplant reconditioned lungs.
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11. |
- Ingemansson, Richard, et al.
(författare)
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The Duration of Negative Pressure Wound Therapy Can Be Reduced Using the HeartShield Device in Patients With Deep Sternal Wound Infection.
- 2014
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Ingår i: Eplasty: Open Access Journal of Plastic and Reconstructive Surgery. - 1937-5719. ; 14:Apr 3, s. 16-16
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Tidskriftsartikel (refereegranskat)abstract
- Background: Heart rupture resulting in lethal bleeding is a devastating complication associated with negative pressure wound therapy (NPWT) in patients with deep sternal wound infection (DSWI). We have previously reported that the use of a protective HeartShield device in combination with NPWT decreases the risk of damage to the heart. This article presents a retrospective analysis of NPWT duration with and without the HeartShield device. Subjects and patients: The study included 6 patients treated with the HeartShield device in combination with NPWT and 6 patients treated with conventional NPWT during the same time period. The duration of active treatment time was measured. Results: The median duration of NPWT was 8 days (range: 6-14 days) in the HeartShield device NPWT group and 14 days in the conventional group (range: 10-18 days). The difference was statistically significant (P < .05). Conclusions: It appears that the treatment of patients with DSWI with the HeartShield device reduces the duration of NPWT.
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12. |
- Ingemansson, Richard, et al.
(författare)
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The HeartShield Device Reduces the Risk for Right Ventricular Damage in Patients With Deep Sternal Wound Infection.
- 2014
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Ingår i: Innovations: Technology and Techniques in Cardiothoracic and Vascular Surgery. - 1556-9845. ; 9:2, s. 137-141
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Tidskriftsartikel (refereegranskat)abstract
- Right ventricular rupture, resulting in serious bleeding, is a life-threatening complication associated with negative-pressure wound therapy (NPWT) in cardiac surgery. The use of a rigid barrier between the heart and the sharp sternal edges has been successfully tested on pigs. In the present article, we demonstrate increased safety in NPWT through the use of the HeartShield device.
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13. |
- Liersch Nordqvist, Annika, et al.
(författare)
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Lungs exposed to 1 hour warm ischemia without heparin before harvesting might be suitable candidates for transplantation.
- 2015
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Ingår i: Journal of Cardiothoracic Surgery. - : Springer Science and Business Media LLC. - 1749-8090. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- The limiting factor for lung transplantation is the lack of donor organs. The usage of lungs from donation after cardiac death (DCD) would dramatically increase donor availability. In the present paper we wanted to investigate lungs exposed to 1 h of warm ischemia without heparin followed by flush-perfusion and cold storage compared to lungs harvested from heart beating donors (HBD) using standard harvesting technique.
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14. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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A compare between myocardial topical negative pressure levels of-25 mmHg and-50 mmHg in a porcine model
- 2008
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Ingår i: BMC Cardiovascular Disorders. - : Springer Science and Business Media LLC. - 1471-2261. ; 8:14
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Tidskriftsartikel (refereegranskat)abstract
- Background: Topical negative pressure (TNP), widely used in wound therapy, is known to stimulate wound edge blood flow, granulation tissue formation, angiogenesis, and revascularization. We have previously shown that application of a TNP of -50 mmHg to the myocardium significantly increases microvascular blood flow in the underlying tissue. We have also shown that a myocardial TNP levels between -75 mmHg and -150 mmHg do not induce microvascular blood flow changes in the underlying myocardium. The present study was designed to elucidate the difference between -25 mmHg and -50 mmHg TNP on microvascular flow in normal and ischemic myocardium. Methods: Six pigs underwent median sternotomy. The microvascular blood flow in the myocardium was recorded before and after the application of TNP using laser Doppler flowmetry. Analyses were performed before left anterior descending artery (LAD) occlusion (normal myocardium), and after 20 minutes of LAD occlusion (ischemic myocardium). Results: A TNP of -25 mmHg significantly increased microvascular blood flow in both normal (from 263.3 +/- 62.8 PU before, to 380.0 +/- 80.6 PU after TNP application, *p = 0.03) and ischemic myocardium (from 58.8 +/- 17.7 PU before, to 85.8 +/- 20.9 PU after TNP application, *p = 0.04). A TNP of -50 mmHg also significantly increased microvascular blood flow in both normal (from 174.2 +/- 20.8 PU before, to 240.0 +/- 34.4 PU after TNP application, *p = 0.02) and ischemic myocardium (from 44.5 +/- 14.0 PU before, to 106.2 +/- 26.6 PU after TNP application, **p = 0.01). Conclusion: Topical negative pressure of -25 mmHg and -50 mmHg both induced a significant increase in microvascular blood flow in normal and in ischemic myocardium. The increase in microvascular blood flow was larger when using -25 mmHg on normal myocardium, and was larger when using -50 mmHg on ischemic myocardium; however these differences were not statistically significant.
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15. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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A rigid barrier between the heart and sternum protects the heart and lungs against rupture during negative pressure wound therapy.
- 2011
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Ingår i: Journal of Cardiothoracic Surgery. - : Springer Science and Business Media LLC. - 1749-8090. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Right ventricular heart rupture is a devastating complication associated with negative pressure wound therapy (NPWT) in cardiac surgery. The use of a rigid barrier has been suggested to offer protection against this lethal complication, by preventing the heart from being drawn up and damaged by the sharp edges of the sternum. The aim of the present study was to investigate whether a rigid barrier protects the heart and lungs against injury during NPWT. METHODS: Sixteen pigs underwent median sternotomy followed by NPWT at -120 mmHg for 24 hours, in the absence (eight pigs) or presence (eight pigs) of a rigid plastic disc between the heart and the sternal edges. The macroscopic appearance of the heart and lungs was inspected after 12 and 24 hours of NPWT. RESULTS: After 24 hours of NPWT at -120 mmHg the area of epicardial petechial bleeding was 11.90 ± 1.10 cm2 when no protective disc was used, and 1.15 ± 0.19 cm2 when using the disc (p < 0.001). Heart rupture was observed in three of the eight animals treated with NPWT without the disc. Lung rupture was observed in two of the animals, and lung contusion and emphysema were seen in all animals treated with NPWT without the rigid disc. No injury to the heart or lungs was observed in the group of animals treated with NPWT using the rigid disc. CONCLUSION: Inserting a rigid barrier between the heart and the sternum edges offers protection against heart rupture and lung injury during NPWT.
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16. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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A Short Period of Ventilation without Perfusion Seems to Reduce Atelectasis without Harming the Lungs during Ex Vivo Lung Perfusion.
- 2013
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Ingår i: Journal of transplantation. - : Hindawi Limited. - 2090-0015 .- 2090-0007. ; 2013
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Tidskriftsartikel (refereegranskat)abstract
- To evaluate the lung function of donors after circulatory deaths (DCDs), ex vivo lung perfusion (EVLP) has been shown to be a valuable method. We present modified EVLP where lung atelectasis is removed, while the lung perfusion is temporarily shut down. Twelve pigs were randomized into two groups: modified EVLP and conventional EVLP. When the lungs had reached 37°C in the EVLP circuit, lung perfusion was temporarily shut down in the modified EVLP group, and positive end-expiratory pressure (PEEP) was increased to 10 cm H2O for 10 minutes. In the conventional EVLP group, PEEP was increased to 10 cm H2O for 10 minutes with unchanged lung perfusion. In the modified EVLP group, the arterial oxygen partial pressure (PaO2) was 18.5 ± 7.0 kPa before and 64.5 ± 6.0 kPa after the maneuver (P < 0.001). In the conventional EVLP group, the PaO2 was 16.8 ± 3.1 kPa and 46.8 ± 2.7 kPa after the maneuver (P < 0.01; P < 0.01). In the modified EVLP group, the pulmonary graft weight was unchanged, while in the conventional EVLP group, the pulmonary graft weight was significantly increased. Modified EVLP with normoventilation of the lungs without ongoing lung perfusion for 10 minutes may eliminate atelectasis almost completely without harming the lungs.
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17. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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C-reactive protein and leucocyte counts drop faster using the HeartShield® device in patients with DSWI.
- 2015
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Ingår i: International Wound Journal. - : Wiley. - 1742-481X .- 1742-4801. ; 12:2, s. 189-194
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Tidskriftsartikel (refereegranskat)abstract
- Right ventricular heart rupture is a devastating complication associated with negative pressure wound therapy (NPWT) in cardiac surgery. The use of a rigid barrier disc (HeartShield™) has been suggested to offer protection against this lethal complication by preventing the heart from being drawn up by the negative pressure and damaged by the sharp sternum bone edges. Seven patients treated with conventional NPWT and seven patients treated with NPWT with a protective barrier disc (HeartShield) were compared with regard to bacterial clearance and infection parameters including C-reactive protein levels and leucocyte counts. C-reactive protein levels and leucocyte counts dropped faster and bacterial clearance occurred earlier in the HeartShield® group compared with the conventional NPWT group. Negative biopsy cultures were shown after 3·1 ± 0·4 NPWT dressing changes in the HeartShield group, and after 5·4 ± 0·6 NPWT dressing changes in the conventional NPWT group (P < 0·001). All patients were followed up with clinical check-up after 3 months. None of the patients in the HeartShield group had any signs of reinfection such as deep sternal wound infection (DSWI) or sternal fistulas, whereas in the conventional NPWT group, two patients had signs of sternal fistulas that demanded hospitalisation. HeartShield hiders the right ventricle to come into contact with the sharp sternal edges during NPWT and thereby protects from heart damage. This study shows that using HeartShield is beneficial in treating patients with DSWI. Improved wound healing by HeartShield may be a result of the efficient drainage of wound effluents from the thoracic cavity.
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18. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Comparative outcome of double lung transplantation using conventional donor lungs and non-acceptable donor lungs reconditioned ex vivo.
- 2010
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Ingår i: Interactive Cardiovascular and Thoracic Surgery. - : Oxford University Press (OUP). - 1569-9285 .- 1569-9293.
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Tidskriftsartikel (refereegranskat)abstract
- A method to evaluate and recondition lungs ex vivo has been tested on donor lungs that have been rejected for transplantation. In the present paper, we compare early postoperative course between the six patients who received reconditioned lungs and the patients who received conventional donor lungs during the same period of time. During 2006 and 2007, a total of 21 patients underwent double sequential lung transplantation at the University Hospital of Lund. Six of those patients received reconditioned lungs. The other 15 patients received conventional donor lungs for transplantation without reconditioning ex vivo. The results are presented as median and interquartile range. Time in intensive care unit (days) between recipients of reconditioned lungs [13 (5-24) days], and recipients of conventional donor lungs [7 (5-12) days], P=0.44. Total hospital stay after transplantation (days) between recipients of reconditioned lungs [52 (47-60) days] and recipients of conventional donor lungs [44 (37-48) days], P=0.9. Ex vivo lung evaluation and reconditioning might not prolong early postoperative course in double lung transplantation. However, given the small number of patients, there might be a failure to detect a difference between the two groups. Keywords: Double lung transplantation; Reconditioned lungs; Clinical outcome.
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19. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Comparative study of the microvascular blood flow in the intestinal wall, wound contraction and fluid evacuation during negative pressure wound therapy in laparostomy using the V.A.C. abdominal dressing and the ABThera open abdomen negative pressure therapy system.
- 2015
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Ingår i: International Wound Journal. - : Wiley. - 1742-481X .- 1742-4801. ; 12:1, s. 83-88
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Tidskriftsartikel (refereegranskat)abstract
- To compare the changes in microvascular blood flow in the small intestinal wall, wound contraction and fluid evacuation, using the established V.A.C. abdominal dressing (VAC dressing) and a new abdominal dressing, the ABThera open abdomen negative pressure therapy system (ABThera dressing), in negative pressure wound therapy (NPWT). Midline incisions were made in 12 pigs, which were subjected to treatment with NPWT using the VAC or ABThera dressing. The microvascular blood flow in the intestinal wall, were measured before and after the application at topical negative pressures of -50, -75 and -125 mmHg, using laser Doppler velocimetry. Wound contraction and fluid evacuation were also measured. Baseline blood flow was defined as 100% in all settings. The blood flow was significantly reduced, to 64·6 ± 6·7% (P < 0·05) after the application of -50 mmHg using the VAC dressing, and to 65·3 ± 9·6% (P < 0·05) after the application of -50 mmHg with the ABThera dressing. The blood flow was significantly reduced, to 39·6 ± 6·7% (P < 0·05) after the application of -125 mmHg using VAC, and to 40·5 ± 6·2% (P < 0·05) after the application of -125 mmHg with ABThera. No significant difference in the reduction in blood flow could be observed between the two groups. The ABThera system gave significantly better fluid evacuation from the wound compared to the VAC system. There was no difference between the dressings regarding the reduction in blood flow, but the ABThera dressing afforded better drainage of the abdomen and better wound contraction than the VAC dressing.
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20. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Effects on drainage of the mediastinum and pleura during negative pressure wound therapy when using a rigid barrier to prevent heart rupture.
- 2011
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Ingår i: International Wound Journal. - 1742-481X. ; 8, s. 454-458
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Tidskriftsartikel (refereegranskat)abstract
- Right ventricular heart rupture is a devastating complication associated with negative pressure wound therapy (NPWT) following cardiac surgery. The use of a rigid disc has been suggested to offer protection against this lethal complication by preventing the heart from being drawn up towards, and damaged by, the sharp sternum edges. The aim of the present study was to compare the wound fluid evacuation from the pericardium and the left pleura when using NPWT with such a disc between the sternal edges and the heart, and when using conventional NPWT. Six pigs underwent median sternotomy followed by NPWT at -120 mmHg, using foam, with or without a rigid plastic disc between the heart and the sternal edges. A 250 ml saline was infused into the pericardium, and the time required for fluid evacuation was measured. A 500 ml saline was infused into the left pleura and the time for fluid evacuation measured. The pericardium was effectively drained of 250 ml fluid in both cases [conventional NPWT: 24 ± 0·7 seconds, NPWT with the disc: 25 ± 1·1 seconds (n.s.)]. The left pleura was effectively drained when using NPWT with the disc, but was not drained at all when using conventional NPWT. The left pleura could be effectively drained of 500 ml fluid when a rigid perforated plastic disc was inserted between the sternal edges and the heart during NPWT. Significantly less drainage of the left pleura was possible when using conventional NPWT without the disc. The pericardium was equally good drained using NPWT with or without the disc.
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21. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Evaluation of continuous and intermittent myocardial topical negative pressure.
- 2008
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Ingår i: Journal of Cardiovascular Medicine. - 1558-2027. ; 9:8, s. 813-819
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Topical negative pressure, commonly used in wound therapy, has been shown to increase blood flow and stimulate angiogenesis in subcutaneous tissue and skeletal muscle. In wound therapy, intermittent negative pressure is often preferred to continuous negative pressure as tissue exposed to intermittent therapy shows twice as much granulation tissue formation than that exposed to continuous pressure after 2 weeks of therapy. The present study was designed to elucidate the differences in microvascular blood flow in the left anterior descending artery area between continuous and intermittent myocardial topical negative pressure of -50 mmHg. METHODS: Six pigs underwent median sternotomy. Laser Doppler probes were inserted horizontally into the heart muscle in the left anterior descending artery area at depths of approximately 5-6 mm. Measurements of microvascular blood flow were performed in normal myocardium and ischemic myocardium during 20 min of countinuous and intermittent topical negative pressure at -50 mmHg. RESULTS: Both continuous and intermittent topical negative pressure of -50 mmHg significantly increased microvascular blood flow in the underlying myocardium: from 56.2 +/- 13.1 perfusion units (PU) before to 132.8 +/- 7.4 PU during countinuous topical negative pressure application (P < 0.05) and from 75.8 +/- 12.1 PU before to 153.6 +/- 4.7 PU during intermittent topical negative pressure application (P < 0.05). CONCLUSION: No statistically significant difference was found between microvascular blood flow during 20 min of continuous and intermittent topical negative pressure at -50 mmHg in this porcine model.
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22. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Haemodynamic effects of negative pressure wound therapy when using a rigid barrier to prevent heart rupture.
- 2011
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Ingår i: International Wound Journal. - 1742-481X. ; 8, s. 385-392
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Tidskriftsartikel (refereegranskat)abstract
- Right ventricular heart rupture is a devastating complication associated with negative pressure wound therapy (NPWT) in cardiac surgery. The use of a rigid barrier has been suggested to offer protection against this lethal complication by preventing the heart from being drawn up and damaged by the sharp sternum bone edges. The aim of this study was to investigate the haemodynamic effects of placing a rigid barrier over the heart to protect it from rupture during NPWT. Eight pigs underwent median sternotomy followed by NPWT at -70 and -120 mmHg, using foam, with or without a rigid plastic disc between the heart and the sternal edges. The heart frequency, cardiac output, mean systemic arterial pressure, mean pulmonary artery pressure, central venous pressure and left atrial pressure were recorded. Cardiac output was not affected by NPWT, regardless of whether a rigid barrier was used. Heart frequency decreased during NPWT without a disc, and showed a tendency towards a decrease when using a rigid disc. The blood pressure decreased during NPWT without a disc, and showed only a tendency towards a decrease when a disc was inserted between the heart and the sternum. In conclusion, the results of this haemodynamic study show that a rigid disc can safely be placed over the heart during NPWT, to prevent heart rupture. The haemodynamic effects of NPWT in sternotomy wounds are slightly reduced by the presence of the rigid disc.
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23. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Heparin does not seem to improve the function of pulmonary grafts for lung transplantation.
- 2013
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Ingår i: Scandinavian Cardiovascular Journal. - : Informa UK Limited. - 1651-2006 .- 1401-7431. ; 47:5, s. 307-313
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Background. It has been debated whether or not heparin infusion before or after non-heart-beating donors are declared dead improves the quality of pulmonary grafts. In clinical lung transplantation with heart-beating donors (HBDs) heparin is routinely infused prior to organ harvesting since it is believed to improve pulmonary grafts by minimizing thrombosis formation in the pulmonary grafts. Here, we raise the question of whether or not the use of heparin in HBDs improves the quality of the pulmonary grafts. Methods. Twelve landrace pigs were divided into two groups of six animals; heparin was given prior to lung harvesting in one group, while the other group did not receive any heparin. The lungs were evaluated using an ex vivo lung perfusion (EVLP) method. Results. No significant difference in arterial oxygen partial pressure (PaO2) was observed between the two groups at an inspired oxygen fraction (FiO2) of 1.0 (mean 69.2 kPa, range 46.1-77.0 in the non-heparin group, and 61.6 kPa, range 47.9-71.4 in the heparin group, p = 0.44), neither in pulmonary vascular resistance: mean 543 ((dyne × s)/cm(5)) (range 280-615) in the non-heparin group and 533 ((dyne × s)/cm(5)) (320-762) in the heparin group (p = 0.99). Conclusions. Heparin did not seem to improve pulmonary graft function in our animal model using conventional HBDs.
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24. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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How to recondition ex vivo initially rejected donor lungs for clinical transplantation: clinical experience from lund university hospital.
- 2011
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Ingår i: Journal of transplantation. - : Hindawi Limited. - 2090-0015 .- 2090-0007. ; 2011:Aug 24
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Tidskriftsartikel (refereegranskat)abstract
- A major problem in clinical lung transplantation is the shortage of donor lungs. Only about 20% of donor lungs are accepted for transplantation. We have recently reported the results of the first six double lung transplantations performed with donor lungs reconditioned ex vivo that had been deemed unsuitable for transplantation by the Scandiatransplant, Eurotransplant, and UK Transplant organizations because the arterial oxygen pressure was less than 40 kPa. The three-month survival of patients undergoing transplant with these lungs was 100%. One patient died due to sepsis after 95 days, and one due to rejection after 9 months. Four recipients are still alive and well 24 months after transplantation, with no signs of bronchiolitis obliterans syndrome. The donor lungs were reconditioned ex vivo in an extracorporeal membrane oxygenation circuit using STEEN solution mixed with erythrocytes, to dehydrate edematous lung tissue. Functional evaluation was performed with deoxygenated perfusate at different inspired fractions of oxygen. The arterial oxygen pressure was significantly improved in this model. This ex vivo evaluation model is thus a valuable addition to the armamentarium in increasing the number of acceptable lungs in a donor population with inferior arterial oxygen pressure values, thereby, increasing the lung donor pool for transplantation. In the following paper we present our clinical experience from the first six patients in the world. We also present the technique we used in detail with flowchart.
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25. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Impact of different topical negative pressure levels on myocardial microvascular blood flow.
- 2008
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Ingår i: Cardiovascular Revascularization Medicine. - : Elsevier BV. - 1878-0938 .- 1553-8389. ; 9:1, s. 29-35
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: We have previously shown that a myocardial topical negative pressure (TNP) of -50 mmHg significantly increases microvascular blood flow in the underlying myocardium in normal, ischemic, and reperfused porcine myocardium. The present study was designed to elucidate the effect of different TNP levels between -50 and -150 mmHg on microvascular flow in normal and ischemic myocardium. MATERIALS AND METHODS: Seven pigs underwent median sternotomy. The microvascular blood flow in the myocardium was recorded, before and after the application of TNP, using laser Doppler velocimetry. Analyses were performed before left anterior descending artery (LAD) occlusion (normal myocardium) and after 20 min of LAD occlusion (ischemic myocardium). RESULTS: A TNP of -50 mmHg significantly increased microvascular blood flow in both normal (from 320.0+/-56.1 PU before TNP application to 435.7+/-65.5 PU after TNP application, P=.028) and ischemic myocardium (from 110.0+/-36.7 PU before TNP application to 194.3+/-56.2 PU after TNP application, P=.012). TNP between -75 and -150 mmHg showed no significant increase in microvascular blood flow in normal or ischemic myocardium. CONCLUSIONS: Of pressures between -50 and -150 mmHg, a TNP of -50 mmHg seems to be the most effective negative pressure concerning significant increase in microvascular blood flow in both normal and ischemic myocardium.
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26. |
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27. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Macroscopic changes during negative pressure wound therapy of the open abdomen using conventional negative pressure wound therapy and NPWT with a protective disc over the intestines
- 2011
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Ingår i: BMC Surgery. - : Springer Science and Business Media LLC. - 1471-2482. ; 11, s. 10-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Higher closure rates of the open abdomen have been reported with negative pressure wound therapy (NPWT) than with other wound management techniques. However, the method has occasionally been associated with increased development of fistulae. We have previously shown that NPWT induces ischemia in the underlying small intestines close to the vacuum source, and that a protective disc placed between the intestines and the vacuum source prevents the induction of ischemia. In the present study we compare macroscopic changes after 12, 24, and 48 hours, using conventional NPWT and NPWT with a protective disc between the intestines and the vacuum source. Methods: Twelve pigs underwent midline incision. Six animals underwent conventional NPWT, while the other six pigs underwent NPWT with a protective disc inserted between the intestines and the vacuum source. Macroscopic changes were photographed and quantified after 12, 24, and 48 hours of NPWT. Results: The surface of the small intestines was red and mottled as a result of petechial bleeding in the intestinal wall in all cases. After 12, 24 and 48 hours of NPWT, the area of petechial bleeding was significantly larger when using conventional NPWT than when using NPWT with the protective disc (9.7 +/- 1.0 cm(2) vs. 1.8 +/- 0.2 cm(2), p < 0.001, 12 hours), (14.5 +/- 0.9 cm(2) vs. 2.0 +/- 0.2 cm(2), 24 hours) (17.0 +/- 0.7 cm(2) vs. 2.5 +/- 0.2 cm(2) with the disc, p < 0.001, 48 hours) Conclusions: The areas of petechial bleeding in the small intestinal wall were significantly larger following conventional NPWT after 12, 24 and 48 hours, than using NPWT with a protective disc between the intestines and the vacuum source. The protective disc protects the intestines, reducing the amount of petechial bleeding.
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28. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Microvascular Blood Flow Changes in the Small Intestinal Wall During Conventional Negative Pressure Wound Therapy and Negative Pressure Wound Therapy Using a Protective Disc Over the Intestines in Laparostomy.
- 2012
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Ingår i: Annals of Surgery. - 1528-1140 .- 0003-4932. ; 255, s. 171-175
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES:: Blood flow changes in the intestines during conventional negative pressure wound therapy (NPWT), and NPWT using a protective disc over the intestines in laparostomy. BACKGROUND:: Higher closure rates of the open abdomen have been reported with NPWT compared with other kinds of wound management. However, the method has been associated with increased development of fistulae. We have compared the changes in blood flow in the intestinal wall using conventional NPWT and NWPT with a protective disc between the intestines and the vacuum source. METHODS:: Midline incisions were made in 10 pigs and either conventional NPWT or NPWT with a disc over the intestines was applied. The microvascular blood flow was measured in the intestinal wall before and after the application of topical negative pressures of -50, -70, and -120 mmHg, using laser Doppler velocimetry. RESULTS:: The blood flow was significantly decreased (by 24%) after the application of conventional NPWT at -50 mmHg, compared with a slight decrease (2%) after the application of NWPT with a protective disc (P < 0.05). The blood flow was significantly decreased (by 54%) after the application of conventional NPWT at -120 mmHg, compared with a slight decrease (17%) after application of NPWT using a protective disc (P < 0.001). CONCLUSIONS:: Inserting a disc between the intestines and the vacuum source in NPWT protects the intestines from ischemia. The decreased blood flow in the intestinal wall may induce ischemia, which could promote the development of intestinal fistulae.
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29. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Myocardial topical negative pressure increases blood flow in hypothermic, ischemic myocardium.
- 2008
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Ingår i: Scandinavian Cardiovascular Journal. - : Informa UK Limited. - 1651-2006 .- 1401-7431. ; 42, s. 345-353
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives. Hypothermia protects the myocardium from oxidative injury during ischemic stress and reperfusion. We have previously shown that topical negative pressure (TNP) of -50 mmHg significantly increases microvascular blood flow in the underlying myocardium in normal, ischemic, and reperfused porcine myocardium. The present study was designed to elucidate the effect of TNP between -50 mmHg and -150 mmHg on microvascular blood flow in ischemic myocardium during hypothermia. Design. The microvascular blood flow in the myocardium was recorded, in seven pigs, using laser Doppler velocimetry. Analyses were performed in the epicardium and in the myocardium, after 40 minutes of occlusion of the LAD followed by cooling to 31 degrees C. Results. A TNP of -50 mmHg applied to the epicardium, from 23.3+/-3.8 PU to 104.2+/-31.3 PU (*p <0.05), and in the myocardium, from 35.0+/-7.2 PU to 74.2+/-21.8 PU (*p <0.05). Conclusions. Only a TNP level of -50 mmHg significantly increased the microvascular blood flow in both the epicardium and in the myocardium during hypothermia.
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30. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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No hypoperfusion is produced in the epicardium during application of myocardial topical negative pressure in a porcine model.
- 2007
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Ingår i: Journal of Cardiothoracic Surgery. - : Springer Science and Business Media LLC. - 1749-8090. ; 2
-
Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT: BACKGROUND: Topical negative pressure (TNP), commonly used in wound therapy, has been shown to increase blood flow and stimulate angiogenesis in skeletal muscle. We have previously shown that a myocardial TNP of -50 mmHg significantly increases microvascular blood flow in the myocardium. When TPN is used in wound therapy (on skeletal and subcutaneous tissue) a zone of relative hypoperfusion is seen close to the wound edge. Hypoperfusion induced by TNP is thought to depend on tissue density, distance from the negative pressure source, and the amount negative pressure applied. When applying TNP to the myocardium, a significant, long-standing zone of hypoperfusion could theoretically cause ischemia, and negative effects on the myocardium. The current study was designed to elucidate whether hypoperfusion was produced during myocardial TNP. METHODS: Six pigs underwent median sternotomy. Laser Doppler probes were inserted horizontally into the heart muscle in the LAD area, at depths of approximately, 1-2 mm. The microvascular blood flow was measured before and after the application of a TNP. Analyses were performed before left anterior descending artery (LAD) occlusion (normal myocardium) and after 20 minutes of LAD occlusion (ischemic myocardium). RESULTS: A TNP of -50 mmHg induced a significant increase in microvascular blood flow in normal myocardium (**p = 0.01), while -125 mmHg did not significantly alter the microvascular blood flow. In ischemic myocardium a TNP of -50 mmHg induced a significant increase in microvascular blood flow (*p = 0.04), while -125 mmHg did not significantly alter the microvascular blood flow. CONCLUSION: No hypoperfusion could be observed in the epicardium in neither normal nor ischemic myocardium during myocardial TNP.
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31. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Pressure transduction and fluid evacuation during conventional negative pressure wound therapy of the open abdomen and NPWT using a protective disc over the intestines
- 2012
-
Ingår i: BMC Surgery. - : Springer Science and Business Media LLC. - 1471-2482. ; 12, s. 4-
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Negative pressure wound therapy (NPWT) has gained acceptance among surgeons, for the treatment of open abdomen, since very high closure rates have been reported with this method, compared to other kinds of wound management for the open abdomen. However, the method has occasionally been associated with increased development of fistulae. We have previously shown that NPWT induces ischemia in the underlying small intestines close to the vacuum source, and that a protective disc placed between the intestines and the vacuum source prevents the induction of ischemia. In this study we compare pressure transduction and fluid evacuation of the open abdomen with conventional NPWT and NPWT with a protective disc. Methods: Six pigs underwent midline incision and the application of conventional NPWT and NPWT with a protective disc between the intestines and the vacuum source. The pressure transduction was measured centrally beneath the dressing, and at the anterior abdominal wall, before and after the application of topical negative pressures of -50, -70 and -120 mmHg. The drainage of fluid from the abdomen was measured, with and without the protective disc. Results: Abdominal drainage was significantly better (p < 0. 001) using NPWT with the protective disc at -120 mmHg (439 +/- 25 ml vs. 239 +/- 31 ml), at -70 mmHg (341 +/- 27 ml vs. 166 +/- 9 ml) and at -50 mmHg (350 +/- 50 ml vs. 151 +/- 21 ml) than with conventional NPWT. The pressure transduction was more even at all pressure levels using NPWT with the protective disc than with conventional NPWT. Conclusions: The drainage of the open abdomen was significantly more effective when using NWPT with the protective disc than with conventional NWPT. This is believed to be due to the more even and effective pressure transduction in the open abdomen using a protective disc in combination with NPWT.
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32. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Sternum wound contraction and distension during negative pressure wound therapy when using a rigid disc to prevent heart and lung rupture.
- 2011
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Ingår i: Journal of Cardiothoracic Surgery. - : Springer Science and Business Media LLC. - 1749-8090. ; 6:1
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: There are increasing reports of deaths and serious complications associated with the use of negative pressure wound therapy (NPWT), of which right ventricular heart rupture is the most devastating. The use of a rigid barrier has been suggested to offer protection against this lethal complication by preventing the heart from being drawn up against the sharp edges of the sternum. The aim of the present study was to determine whether a rigid barrier can be safely inserted over the heart with regard to the sternum wound edge movement. METHODS: Sternotomy wounds were created in eight pigs. The wounds were treated with NPWT at -40, -70, -120 and -170 mmHg in the presence and absence of a rigid barrier between the heart and the edges of the sternum. Wound contraction upon NPWT application, and wound distension under mechanical traction to draw apart the edges of the sternotomy were evaluated. RESULTS: Wound contraction resulting from NPWT was similar with and without the rigid barrier. When mechanical traction was applied to a NPWT treated sternum wound, the sternal edges were pulled apart. Wound distension upon traction was similar in the presence and absence of a the rigid barrier during NPWT. CONCLUSIONS: A rigid barrier can safely be inserted between the heart and the edges of the sternum to protect the heart and lungs from rupture during NPWT. The sternum wound edge is stabilized equally well with as without the rigid barrier during NPWT.
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33. |
- Lindstedt Ingemansson, Sandra, et al.
(författare)
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Topical negative pressure effects on coronary blood flow in a sternal wound model.
- 2008
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Ingår i: International Wound Journal. - 1742-481X. ; 5:4, s. 503-509
-
Tidskriftsartikel (refereegranskat)abstract
- Several studies have suggested that mediastinitis is a strong predictor for poor long-term survival after coronary artery bypass surgery (CABG). In those studies, several conventional wound-healing techniques were used. Previously, we have shown no difference in long-term survival between CABG patients with topical negative pressure (TNP)-treated mediastinitis and CABG patients without mediastinitis. The present study was designed to elucidate if TNP, applied over the myocardium, resulted in an increase of the total amount of coronary blood flow. Six pigs underwent median sternotomy. The coronary blood flow was measured, before and after the application of TNP (-50 mmHg), using coronary electromagnetic flow meter probes. Analyses were performed before left anterior descending artery (LAD) occlusion (normal myocardium) and after 20 minutes of LAD occlusion (ischaemic myocardium). Normal myocardium: 171.3 +/- 14.5 ml/minute before to 206.3 +/- 17.6 ml/minute after TNP application, P < 0.05. Ischaemic myocardium: 133.7 +/- 18.4 ml/minute before to 183.2 +/- 18.9 ml/minute after TNP application, P < 0.05. TNP of -50 mmHg applied over the LAD region induced a significant increase in the total coronary blood flow in both normal and ischaemic myocardium.
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34. |
- Malmsjö, Malin, et al.
(författare)
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Comparison of bacteria and fungus-binding mesh, foam and gauze as fillers in negative pressure wound therapy - pressure transduction, wound edge contraction, microvascular blood flow and fluid retention.
- 2013
-
Ingår i: International Wound Journal. - 1742-481X. ; 10:5, s. 597-605
-
Tidskriftsartikel (refereegranskat)abstract
- Bacteria- and fungus-binding mesh binds and inactivates bacteria and fungus, which makes it interesting, alternative, wound filler for negative pressure wound therapy (NPWT). This study was conducted to compare the performance of pathogen-binding mesh, foam and gauze as wound fillers in NPWT with regard to pressure transduction, fluid retention, wound contraction and microvascular blood flow. Wounds on the backs of 16 pigs were filled with pathogen-binding mesh, foam or gauze and treated with NPWT. The immediate effects of 0, -40, -60, -80 and -120 mmHg, on pressure transduction and blood flow were examined in eight pigs using laser Doppler velocimetry. Wound contraction and fluid retention were studied during 72 hours of NPWT at -80 and -120 mmHg in the other eight pigs. Pathogen-binding mesh, gauze and foam provide similar pressure transduction to the wound bed during NPWT. Blood flow was found to decrease 0·5 cm laterally from the wound edge and increase 2·5 cm from the wound edge, but was unaltered 5·0 cm from the wound edge. The increase in blood flow was similar with all wound fillers. The decrease in blood flow was more pronounced with foam than with gauze and pathogen-binding mesh. Similarly, wound contraction was more pronounced with foam, than with gauze and pathogen-binding mesh. Wound fluid retention was the same in foam and pathogen-binding mesh, while more fluid was retained in the wound when using gauze. The blood flow 0·5-5 cm from the wound edge and the contraction of the wound during NPWT were similar when using pathogen-binding mesh and gauze. Wound fluid was efficiently removed through the pathogen-binding mesh, which may explain previous findings that granulation tissue formation is more rapid under pathogen-binding mesh than under gauze. This, in combination with its pathogen-binding properties, makes this mesh an interesting wound filler for use in NPWT.
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35. |
- Malmsjö, Malin, et al.
(författare)
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Effects of foam or gauze on sternum wound contraction, distension and heart and lung damage during negative pressure wound therapy of porcine sternotomy wounds.
- 2010
-
Ingår i: Interactive Cardiovascular and Thoracic Surgery. - : Oxford University Press (OUP). - 1569-9285 .- 1569-9293.
-
Tidskriftsartikel (refereegranskat)abstract
- The study was performed to compare the effects of negative-pressure wound therapy (NPWT) using gauze and foam on wound edge movement and the macroscopic appearance of the heart and lungs after NPWT. Sternotomy wounds were created in 6 kg pigs. Negative pressures of -40, -70, -120 and -160 mmHg were applied and the following were evaluated: wound contraction, distension and the macroscopic appearance of the heart and lungs after NPWT. Wound contraction was greater when using foam than gauze (3.5±0.3 cm and 1.3±0.2 cm, respectively, P<0.01). The application of traction to the lateral edges of the sternotomy resulted in greater wound distention with foam than with gauze (5.3±0.3 cm and 3.6±0.2 cm, respectively, P<0.001). After using foam, the surface of the heart was red and mottled, and lung emphysema and sometimes, lung rupture were observed. After using gauze, the organ surface had no markings. The study shows that foam allows greater wound contraction and distension than gauze. This movement of the wound edges may cause damage to the underlying organs. There is less damage to the heart and lungs when using gauze than foam. Keywords: Animal model; Wound contraction; Experimental surgery; Heart rupture; Negative-pressure wound therapy; Sternotomy wound.
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36. |
- Malmsjö, Malin, et al.
(författare)
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Effects on heart pumping function when using foam and gauze for negative pressure wound therapy of sternotomy wounds
- 2011
-
Ingår i: Journal of Cardiothoracic Surgery. - : Springer Science and Business Media LLC. - 1749-8090. ; 6
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Negative pressure wound therapy (NPWT) has remarkable effects on the healing of poststernotomy mediastinitis. Foam is presently the material of choice for NPWT in this indication. There is now increasing interest in using gauze, as this has proven successful in the treatment of peripheral wounds. It is important to determine the effects of NPWT using gauze on heart pumping function before it can be used for deep sternotomy wounds. The aim was to examine the effects of NPWT when using gauze and foam on the heart pumping function during the treatment of a sternotomy wound. Methods: Eight pigs underwent median sternotomy followed by NPWT at -40, -70, -120 and -160 mmHg, using foam or gauze. The heart frequency, cardiac output, mean systemic arterial pressure, mean pulmonary artery pressure, central venous pressure and left atrial pressure were recorded. Results: Cardiac output was not affected by NPWT using gauze or foam. Heart frequency decreased during NPWT when using foam, but not gauze. Treatment with foam also lowered the central venous pressure and the left atrial pressure, while gauze had no such effects. Mean systemic arterial pressure, mean pulmonary artery pressure and systemic vascular resistance were not affected by NPWT. Similar haemodynamic effects were observed at all levels of negative pressure studied. Conclusions: NPWT using foam results in decreased heart frequency and lower right and left atrial filling pressures. The use of gauze in NPWT did not affect the haemodynamic parameters studied. Gauze may thus provide an alternative to foam for NPWT of sternotomy wounds.
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37. |
- Malmsjö, Malin, et al.
(författare)
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Influence on pressure transduction when using different drainage techniques and wound fillers (foam and gauze) for negative pressure wound therapy.
- 2010
-
Ingår i: International Wound Journal. - 1742-481X. ; 7, s. 406-412
-
Tidskriftsartikel (refereegranskat)abstract
- Pressure transduction to the wound bed in negative pressure wound therapy (NPWT) is crucial in stimulating the biological effects ultimately resulting in wound healing. In clinical practice, either foam or gauze is used as wound filler. Furthermore, two different drainage techniques are frequently employed. One involves the connection of a non-perforated drainage tube to the top of the dressing, while the other involves the insertion of perforated drains into the dressing. The aim of this study was to examine the efficacy of these two different wound fillers and drainage systems on pressure transduction to the wound bed in a challenging wound (the sternotomy wound). Six pigs underwent median sternotomy. The wound was sealed for NPWT using different wound fillers (foam or gauze) and drainage techniques (see earlier). Pressures between 0 and -175 mmHg were applied and the pressure in the wound was measured using saline-filled catheters sutured to the bottom of the wound (over the anterior surface of the heart) and to the side of the wound (on the thoracic wall). The negative pressure on the wound bed increased linearly with the negative pressure delivered by the vacuum source. In a dry wound, the pressure transduction was similar when using the different wound fillers (foam and gauze) and drainage techniques. In a wet wound, pressure transduction was better when using a perforated drainage tube inserted into the wound filler than a non-perforated drainage tube connected to the top of the dressing (-116 +/- 1 versus -73 +/- 4 mmHg in the wound at a delivered pressure of -125 mmHg for foam, P < 0.01), regardless of the type of wound filler. Gauze and foam are equally effective at delivering negative pressure to the wound bed. Perforated drainage tubes inserted into the wound filler are more efficient than a non-perforated drainage tubes connected to the top of the dressing. The choice of drainage technique may be particularly important in wounds with a large volume of exudate.
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38. |
- Malmsjö, Malin, et al.
(författare)
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Negative Pressure Wound Therapy-associated Tissue Trauma and Pain: A Controlled In vivo Study Comparing Foam and Gauze Dressing Removal by Immunohistochemistry for Substance P and Calcitonin Gene-related Peptide in the Wound Edge.
- 2011
-
Ingår i: Ostomy - Wound Management. - 0889-5899. ; 57:12, s. 30-35
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Tidskriftsartikel (refereegranskat)abstract
- Pain upon negative pressure wound therapy (NPWT) dressing removal has been reported and is believed to be associ- ated with the observation that granulation tissue grows into foam. Wound tissue damage upon removal of the foam may cause the reported pain. Calcitonin gene-related peptide (CGRP) and substance P are neuropeptides that cause inflam- mation and signal pain and are known to be released when tissue trauma occurs. The aim of this controlled in vivo study was to compare the expression of CGRP and substance P in the wound bed in control wounds and following NPWT and foam or gauze dressing removal. Eight pigs with two wounds each were treated with open-pore structure polyurethane foam or AMD gauze and NPWT of 0 (control) or -80 mm Hg for 72 hours. Following removal of the wound filler, the ex- pression of CGRP and substance P was measured, using arbitrary units, in sections of biopsies from the wound bed using immunofluorescence techniques. Substance P and CGRP were more abundant in the wound edge following the removal of foam than of gauze dressings and least abundant in control wounds. The immunofluorescence staining of the wound edge for CGRP was 52 ± 3 au after the removal of gauze and 97 ± 5 au after the removal of foam (P <0.001). For substance P, the staining was 55 ± 3 au after gauze removal and 95 ± 4 au after foam removal (P <0.001). CGRP and substance P staining was primarily located to nerves and leukocytes. The increase in CGRP and substance P immuno- fluorescence was especially prominent in the dermis but also was seen in subcutaneous and muscle tissue. Using gauze may be one way of reducing NPWT dressing change-related pain. New wound fillers designed to optimize granulation tissue formation and minimize pain issues presumably will be developed in the near future.
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39. |
- Malmsjö, Malin, et al.
(författare)
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Use of bacteria- and fungus-binding mesh in negative pressure wound therapy provides significant granulation tissue without tissue ingrowth.
- 2014
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Ingår i: Eplasty: Open Access Journal of Plastic and Reconstructive Surgery. - 1937-5719. ; 14, s. 3-3
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Bacteria- and fungus-binding mesh traps and inactivates bacteria and fungus, which makes it interesting, alternative, and wound filler for negative pressure wound therapy (NPWT). The aim of this study was to compare pathogen-binding mesh, black foam, and gauze in NPWT with regard to granulation tissue formation and ingrowth of wound bed tissue in the wound filler. Methods: Wounds on the backs of 8 pigs underwent 72 hours of NPWT using pathogen-binding mesh, foam, or gauze. Microdeformation of the wound bed and granulation tissue formation and the force required to remove the wound fillers was studied. Results: Pathogen-binding mesh produced more granulation tissue, leukocyte infiltration, and tissue disorganization in the wound bed than gauze, but less than foam. All 3 wound fillers caused microdeformation of the wound bed surface. Little force was required to remove pathogen-binding mesh and gauze, while considerable force was needed to remove foam. This is the result of tissue growth into the foam, but not into pathogen-binding mesh or gauze, as shown by examination of biopsy sections from the wound bed. Conclusions: This study shows that using pathogen-binding mesh as a wound filler for NPWT leads to a significant amount of granulation tissue in the wound bed, more than that with gauze, but eliminates the problems of ingrowth of the wound bed into the wound filler. Pathogen-binding mesh is thus an interesting wound filler in NPWT.
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40. |
- Mokhtari, Arash, et al.
(författare)
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Haemodynamic effects of -75 mmHg negative pressure therapy in a porcine sternotomy wound model.
- 2009
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Ingår i: International Wound Journal. - 1742-481X. ; 6:1, s. 48-54
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Tidskriftsartikel (refereegranskat)abstract
- Previous research has shown -125 mmHg to be the optimal negative pressure for creating an environment that promotes wound healing, and this has therefore been adopted as a standard pressure for patients with deep sternal wound infection. However, it has not yet been clearly shown that -125 mmHg is the optimal pressure from a haemodynamic point of view. Furthermore, there have been reports of cardiac rupture during -125 mmHg negative pressure therapy. We therefore studied the effects of a lower pressure: -75 mmHg. Twelve pigs were used. After median sternotomy, sealed negative pressure therapy of -75 mmHg was applied. Baseline measurements were made and continuous recording of the cardiac output, end-tidal CO(2) production, mean arterial pressure, mean pulmonary pressure (pulmonary artery pressure), systemic vascular resistance, pulmonary vascular resistance, left atrial pressure and central venous pressure was started. Six pigs served as controls. No statistically significant difference was observed in any of the haemodynamic parameters studied, compared with the controls. The present study shows that, with a suitable foam application technique, -75 mmHg can be applied without compromising the central haemodynamics.
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41. |
- Pierre, Leif, et al.
(författare)
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Is it possible to further improve the function of pulmonary grafts by extending the duration of lung reconditioning using ex vivo lung perfusion?
- 2013
-
Ingår i: Perfusion. - : SAGE Publications. - 1477-111X .- 0267-6591. ; 28:4, s. 322-327
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The method of ex vivo lung perfusion (EVLP) has been suggested as a reliable means of differentiating between "good" and "poor" pulmonary grafts in marginal donors as, when grafts identified as good by this method are transplanted, the results do not differ from those using lungs fulfilling standard criteria. The EVLP method is also thought to improve pulmonary grafts by reducing lung edema and eliminating lung atelectasis. In the present study, we investigated whether the pulmonary graft could be further improved by extending the duration of EVLP.Methods and Materials:Six Landrace pigs were used. The lungs were reconditioned and evaluated, using the EVLP method, as double lungs. After the initial evaluation, EVLP was continued for a further 90 minutes. RESULTS: The arterial oxygen level (pO(2)) was 60.8 ± 4.8 kPa after the standard 60 minutes of EVLP and 67.1 ± 2.2 kPa after 150 minutes (p = 0.48). The pulmonary vascular resistance was 453 ± 78 dyne*s/cm(5) after 60, 90, 120 and 150 minutes of EVLP (p = 1.0). The pulmonary artery pressure was 17.8 ± 1.0 mmHg after 60, 90, 120, and 150 minutes of EVLP (p = 1.0) and the pulmonary artery flow was 3.5 ± 0.4 l/min after 60, 90, 120, and 150 minutes of EVLP (p = 1.0). The mean weight of the pulmonary grafts after harvesting was 574 ± 20 g at the beginning of EVLP 541 ± 24 g and, after 150 min of EVLP, 668 ± 33 (p = 0.011). CONCLUSIONS: The blood gases and hemodynamic parameters in the pulmonary grafts did not improve as a result of the extra 90 minutes of EVLP. However, the weight of the pulmonary graft increased significantly with increasing duration of EVLP, indicating lung perfusion injury.
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42. |
- Pierre, Leif, et al.
(författare)
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Ventilation in situ after cardiac death improves pulmonary grafts exposed to 2 hours of warm ischemia
- 2015
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Ingår i: Scandinavian Cardiovascular Journal. - : Informa UK Limited. - 1651-2006 .- 1401-7431. ; 49:5, s. 293-298
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Tidskriftsartikel (refereegranskat)abstract
- Background. The pulmonary donor pool would increase substantially if lungs could be donated after cardiac death (DCD). There have been ethical and legal obstacles since administration of heparin and cooling has to be done immediately after cardiac death. This study examines whether ventilation of DCD lungs without administering heparin or cooling the lungs after cardiac death could improve graft function. Method. Twelve donor pigs with a mean bodyweight of 70 kg were randomized into two groups. Six animals were ventilated in situ with 50% oxygen, 4 L/min, and 5 cm H2O in positive end-expiratory pressure or PEEP for 2 h after cardiac death. Six animals served as non-ventilated controls and were exposed to warm ischemia for 2 h. After 2 h, all lungs were harvested and flush perfused with Perfadex (R) solution and stored at 8 degrees C for another 2 h. An ex vivo lung perfusion or EVLP circuit was used for evaluation. Results. Non-ventilated lungs developed pulmonary edema, and had highly impaired blood gas levels and a significantly increased weight. The ventilated lungs demonstrated excellent blood gas levels and unchanged weight. Conclusion. The increase in tolerable warm ischemic time in combination with avoiding heparinization and cooling might facilitate the use of DCD lungs for transplantation.
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43. |
- Sjögren, Johan, et al.
(författare)
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Negative-pressure wound therapy following cardiac surgery: bleeding complications and 30-days mortality in 176 patients with deep sternal wound infection.
- 2011
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Ingår i: Interactive Cardiovascular and Thoracic Surgery. - : Oxford University Press (OUP). - 1569-9285 .- 1569-9293. ; 12:2, s. 117-120
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Tidskriftsartikel (refereegranskat)abstract
- Negative-pressure wound therapy (NPWT) has been used for the treatment of deep sternal wound infection (DSWI) with promising results. However, questions have been raised regarding the potential risk of right ventricle (RV) rupture during treatment. In the present study, we evaluate our clinical experience of NPWT focusing on RV rupture and major bleeding complications and its potentially negative impact on 30-day mortality during an 11-year period. Serious bleeding complications during NPWT were reviewed for 176 patients treated for DSWI between January 1999 and April 2010. The 30-day mortality following DSWI was 1.1% (2/176). Four patients (2.3%) suffered bleeding from the RV rupture during NPWT of the sternal wound (two spontaneous and two debridement related). Furthermore, two patients had debridement-related bleedings from the venous bypass grafts during wound dressing change. The very low 30-day mortality (1.1%) following DSWI supports the use of NPWT. Overall, even if major bleeding complications may occur, the risk of RV rupture seems to be outweighed by the benefit of superior infection control. However, surgical experience is recommended when debriding sternal wounds and we recommend the use of a wound dressing, such as paraffin gauze, in order to protect the RV from direct contact with the polyurethane foam. Keywords: Wound infection; Sternum; Negative-pressure wound therapy; Outcome.
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44. |
- Sjögren, Johan, et al.
(författare)
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Vakuumassisterad sår- behandling ger goda kliniska resultat God läkning vid komplicerade sår--djupa sternuminfektioner ett exempel.
- 2008
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Ingår i: Läkartidningen. - 0023-7205. ; 105:40, s. 2773-2776
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Tidskriftsartikel (refereegranskat)abstract
- acuum-assisted closure (V.A.C.®) is a novel treatment for wound healing, which has been used extensively during the last years in a growing number of clinical applications. This wound-healing technique is based on the application of local negative pressure to a wound. During treatment with vacuum-assisted closure, several beneficial wound healing mechanisms are initiated. Topical negative pressure increases the microvascular blood flow in the surrounding tissue and reduces wound tissue oedema and wound size. Furthermore, the stimulation of growth factors and neoangiogenesis facilitates the formation of granulation tissue in the wound. Vacuum-assisted closure has been widely adopted as a standard treatment for deep sternal wound infections following cardiac surgery since topical negative pressure combines several advantageous features from conventional surgical techniques. However, although it is effective, vacuum-assisted closure must always be used in combination with proper surgical revision and adequate antibiotic therapy in order to obtain optimal results.
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45. |
- Torbrand, Christian, et al.
(författare)
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Sympathetic and sensory nerve activation during negative pressure therapy of sternotomy wounds.
- 2008
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Ingår i: Interactive cardiovascular and thoracic surgery. - : Oxford University Press (OUP). - 1569-9285 .- 1569-9293. ; 7:6, s. 1067-70
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Tidskriftsartikel (refereegranskat)abstract
- Negative pressure wound therapy (NPWT) has been adopted as the first-line treatment for poststernotomy mediastinitis as a result of the excellent clinical outcome. The knowledge concerning the effects of NPWT on the cardiovascular system and homeostasis is still limited. The aim of the present study was to investigate whether the plasma levels of neurohormones change during NPWT. Six pigs underwent median sternotomy followed by NPWT at -125 mmHg. The plasma levels of noradrenaline, adrenaline, neuropeptide Y, substance P, vasoactive intestinal peptide (VIP), and calcitonin gene-related peptide (CGRP) were determined before (0 min) and 5, 20, 60 and 180 min after the application of NPWT. The results show a transient increase in the plasma levels of noradrenaline and adrenaline when NPWT was applied. The plasma level of the adrenergic co-transmitter neuropeptide Y was higher in NPWT--than in sham-treated pigs, after 180 min of negative pressure. After 180 min of NPWT there was an increase in the plasma levels of the sensory nerve transmitter substance P, while no such effect was observed for CGRP or VIP. In conclusion, the results suggest sympathetic nerve activation during NPWT. This may be the result of an increase in workload on the heart during the initial phase of NPWT.
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46. |
- Acosta, Stefan, et al.
(författare)
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Engaging patients and caregivers in establishing research priorities for aortic dissection
- 2019
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Ingår i: SAGE Open Medicine. - : Sage Publications. - 2050-3121. ; 7, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: The aim of this study was to establish the top 10 research uncertainties in aortic dissection together with the patient organization Aortic Dissection Association Scandinavia using the James Lind Alliance concept. Methods: A pilot survey aiming to identify uncertainties sent to 12 patients was found to have high content validity (scale content validity index = 0.91). An online version of the survey was thereafter sent to 30 patients in Aortic Dissection Association Scandinavia and 45 caregivers in the field of aortic dissection. Research uncertainties of aortic dissection were gathered, collated and processed. Results: Together with research priorities retrieved from five different current guidelines, 94 uncertainties were expressed. A shortlist of 24 uncertainties remained after processing for the final workshop. After the priority-setting process, using facilitated group format technique, the ranked final top 10 research uncertainties included diagnostic tests for aortic dissection; patient information and care continuity; quality of life; endovascular and medical treatment; surgical complications; rehabilitation; psychological consequences; self-care; and how to improve prognosis. Conclusion: These ranked top 10 important research priorities may be used to justify specific research in aortic dissection and to inform healthcare research funding decisions.
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47. |
- Anesäter, Erik, et al.
(författare)
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The influence of different sizes and types of wound fillers on wound contraction and tissue pressure during negative pressure wound therapy.
- 2011
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Ingår i: International Wound Journal. - 1742-481X. ; 8, s. 336-342
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Tidskriftsartikel (refereegranskat)abstract
- Negative pressure wound therapy (NPWT) contracts the wound and alters the pressure in the tissue of the wound edge, which accelerates wound healing. The aim of this study was to examine the effect of the type (foam or gauze) and size (small or large) of wound filler for NPWT on wound contraction and tissue pressure. Negative pressures between -20 and -160 mmHg were applied to a peripheral porcine wound (n = 8). The pressure in the wound edge tissue was measured at distances of 0·1, 0·5, 1·0 and 2·0 cm from the wound edge and the wound diameter was determined. At 0·1 cm from the wound edge, the tissue pressure decreased when NPWT was applied, whereas at 0·5 cm it increased. Tissue pressure was not affected at 1·0 or 2·0 cm from the wound edge. The tissue pressure, at 0·5 cm from the wound edge, was greater when using a small foam than when using than a large foam. Wound contraction was greater when using a small foam than when using a large foam during NPWT. Gauze resulted in an intermediate wound contraction that was not affected by the size of the gauze filler. The use of a small foam to fill the wound causes considerable wound contraction and may thus be used when maximal mechanical stress and granulation tissue formation are desirable. Gauze or large amounts of foam result in less wound contraction which may be beneficial, for example when NPWT causes pain to the patient.
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48. |
- Birke-Sorensen, H., et al.
(författare)
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Evidence-based recommendations for negative pressure wound therapy: Treatment variables (pressure levels, wound filler and contact layer) - Steps towards an international consensus
- 2011
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Ingår i: Journal of Plastic, Reconstructive and Aesthetic Surgery. - : Elsevier BV. - 1878-0539 .- 1748-6815. ; 64, s. 1-16
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Forskningsöversikt (refereegranskat)abstract
- Negative pressure wound therapy (NPWT) is becoming a commonplace treatment in many clinical settings. New devices and dressings are being introduced. Despite widespread adoption, there remains uncertainty regarding several aspects of NPWT use. To respond to these gaps, a global expert panel was convened to develop evidence-based recommendations describing the use of NPWT. In a previous communication, we have reviewed the evidence base for the use of NPWT within trauma and reconstructive surgery. In this communication, we present results of the assessment of evidence relating to the different NPWT treatment variables: different wound fillers (principally foam and gauze); when to use a wound contact layer; different pressure settings; and the impact of NPWT on bacterial bioburden. Evidence-based recommendations were obtained by a systematic review of the literature, grading of evidence and drafting of the recommendations by a global expert panel. Evidence and recommendations were graded according to the Scottish Intercollegiate Guidelines Network (SIGN) classification system. In general, there is relatively weak evidence on which to base recommendations for any one NPWT treatment variable over another. Overall, 14 recommendations were developed: five for the choice of wound filler and wound contact layer, four for choice of pressure setting and five for use of NPWT in infected wounds. With respect to bioburden, evidence suggests that reduction of bacteria in wounds is not a major mode of action of NPWT. (C) 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
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49. |
- Bolys, Ramunas, et al.
(författare)
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Vascular function in the cadaver up to six hours after cardiac arrest
- 1999
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Ingår i: The Journal of Heart and Lung Transplantation. - 1557-3117. ; 18:6, s. 582-586
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The aim of the study was to evaluate how well vascular function is retained in a cadaver kept in a room with a temperature of 21 degrees C. METHODS: The aorta and pulmonary artery of rats were investigated in organ baths as fresh controls and after 1, 2, 3, or 6 hours' storage in the cadaver. Six-hour-old cadaver aortas were transplanted and investigated after 24 hours and 60 days. RESULTS: After 3 hours' storage there was no significant decrease in smooth muscle contractile function in either aorta or pulmonary artery. After 6 hours' storage both the aorta and the pulmonary artery demonstrated a significant decrease in smooth muscle contractile function, 30% (p < 0.05) and 44% (p < 0.001), respectively, compared to fresh controls. Storing the aorta for 2 hours and the pulmonary artery for 6 hours caused no significant decrease in endothelium-dependent relaxing function. In aorta segments investigated after 3 and 6 hours there was a significant decrease in endothelium-dependent relaxation, 12% (p < 0.05) and 29% (p < 0.001), respectively. Six-hour-old cadaver aortas transplanted and investigated after 24 hours or 60 days demonstrated no significant changes in endothelium-dependent relaxation and smooth muscle function compared to fresh controls. CONCLUSION: The pulmonary artery can tolerate 3 hours of warm ischemia in the nonheart-beating cadaver without loss of endothelium-dependent relaxation and smooth muscle function. The dysfunction seen in 6-hour-old cadaver aortas was normalized after transplantation and 24 hours of reperfusion.
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50. |
- Borgquist, Ola, et al.
(författare)
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Individualizing the Use of Negative Pressure Wound Therapy for Optimal Wound Healing: A Focused Review of the Literature
- 2011
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Ingår i: Ostomy - Wound Management. - 0889-5899. ; 57:4, s. 44-44
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Forskningsöversikt (refereegranskat)abstract
- Currently available research suggests that negative pressure wound therapy (NPWT) creates a moist wound healing environment, drains exudate, reduces tissue edema, contracts the wound edges, mechanically stimulates the wound bed, and influences blood perfusion at the wound edge, which may lead to angiogenesis and the formation of granulation tissue. Although no clear evidence is available that NPWT accelerates wound healing compared to other interventions or that one form of NPWT is better than another, preclinical research suggests that the most commonly used dressings, level of negative pressure, and application mode (continuous, intermittent, or variable) may not be optimal for all patients. To summarize available literature related to these NPWT choices, pertinent literature published between 2005 and 2010 was reviewed. Preclinical study results suggest that the maximal biological effect of NPWT at the wound edge often can be achieved at -80 mm Hg and that foam dressings may be advantageous for large defect wounds, whereas gauze dressings may be more suitable for smaller wounds or when scar formation or pain is a concern. Preclinical research results also suggest that intermittent or variable pressure application has a better effect on granulation tissue formation than continuous application. The variable pressure mode maintains a negative pressure environment at lower pressure settings without dramatic fluctuations inherent to intermittent (on-and-off) pressure. Prospective, controlled clinical studies are needed to compare NPWT to other advanced wound care protocols of care and to ascertain the effect of various NPWT methods and regimens on outcomes of care.
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