| 1. |
- Ahlström, Katarina, 1966, et al.
(författare)
-
Metabolic responses in ischemic myocardium after inhalation of carbon monoxide.
- 2009
-
Ingår i: Acta Anaesthesiol Scand. - : Wiley. - 1399-6576 .- 0001-5172. ; 53:8, s. 1036-42
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: To clarify the mechanisms of carbon monoxide (CO) tissue-protective effects, we studied energy metabolism in an animal model of acute coronary occlusion and pre-treatment with CO. METHODS: In anesthetized pigs, a coronary snare and microdialysis probes were placed. CO (carboxyhemoglobin 5%) was inhaled for 200 min in test animals, followed by 40 min of coronary occlusion. Microdialysate was analyzed for lactate and glucose, and myocardial tissue samples were analyzed for adenosine tri-phosphate, adenosine di-phosphate, and adenosine mono-phosphate. RESULTS: Lactate during coronary occlusion was approximately half as high in CO pre-treated animals and glucose levels decreased to a much lesser degree during ischemia. Energy charge was no different between groups. CONCLUSIONS: CO in the low-doses tested in this model results in a more favorable energy metabolic condition in that glycolysis is decreased in spite of maintained energy charge. Further work is warranted to clarify the possible mechanistic role of energy metabolism for CO protection.
|
|
| 2. |
- Bohm, Katarina, et al.
(författare)
-
Dispatcher-assisted telephone-guided cardiopulmonary resuscitation: an underused lifesaving system.
- 2007
-
Ingår i: Eur J Emerg Med. - 0969-9546. ; 14:5, s. 256-9
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Our purpose with this investigation was to (i) estimate how often telephone-guided cardiopulmonary resuscitation was offered from emergency medical service dispatchers in Stockholm, (ii) study the willingness to perform cardiopulmonary resuscitation, and (iii) assess factors that could mislead the dispatcher in identifying the patient as a cardiac arrest victim. METHODS: In this prospective study, 313 consecutive emergency calls of out-of-hospital cardiac arrest were obtained from the Swedish Cardiac Arrest Register. Seventy-six cases of out-of-hospital cardiac arrest fulfilled the inclusion criteria. All alarm calls were tape-recorded and analyzed according to a standardized protocol. RESULTS: Dispatchers offered bystanders telephone instructions for cardiopulmonary resuscitation in 47% (n=36) of the cases and, among these, cardiopulmonary resuscitation instructions were given in 69% (n=25). Only 6% (n=2) of bystanders were not willing to perform cardiopulmonary resuscitation. Signs of breathing (suspected agonal breathing) were described in 45% of the cases. Cardiopulmonary resuscitation was offered to 23% (n=10) of patients with signs of breathing versus 92% (n=23) of those who were not breathing (P<0.001). CONCLUSIONS: Despite the fact that the vast majority of bystanders are willing to take part in telephone-guided cardiopulmonary resuscitation, emergency medical service dispatchers offer telephone-guided cardiopulmonary resuscitation in about only half of cases. Signs of breathing (agonal breathing) are often mistaken for normal breathing and are a cause of delay in the diagnosis of cardiac arrest.
|
|
| 3. |
- Claesson, Jonas, et al.
(författare)
-
Evaluation of intestinal preconditioning in a porcine model using classic ischemic preconditioning or lung recruitment maneuvers.
- 2008
-
Ingår i: Shock. - : Ovid Technologies (Wolters Kluwer Health). - 1073-2322 .- 1540-0514. ; 21:1, s. 98-103
-
Tidskriftsartikel (refereegranskat)abstract
- To test the hypotheses that repeated brief intestinal ischemic insults would elicit an intestinal preconditioning response to a subsequent intestinal I/R injury and that a similar response would be elicited by repeated lung recruitment maneuvers (RMs). Randomized experimental controlled animal study. University hospital animal laboratory. Eighteen anesthetized pigs. Animals were randomized to one of three groups, with six animals in each group. Control group 75-min superior mesenteric artery (SMA) occlusion followed by 60-min reperfusion. Ischemic preconditioning group, three 5-min-long SMA occlusions preceding 75-min SMA occlusion and 60-min reperfusion. Recruitment maneuver (RM) group, three 2-min-long RMs preceding 75-min SMA occlusion and 60-min reperfusion. We measured systemic and mesenteric hemodynamic parameters, jejunal mucosal perfusion, net mesenteric lactate flux, jejunal tissue oxygen tension, and mesenteric oxygenation. Every 15 min, jejunal microdialysate samples were collected and analyzed for glucose, lactate, and glycerol. Jejunal tissue samples were collected postmortem. After occlusion of SMA, regional parameters in all groups indicated abolished perfusion and gradually increasing intraluminal microdialysate lactate and glycerol levels. At reperfusion, regional parameters indicated mesenteric hyperperfusion, whereas microdialysis markers of mucosal anaerobic metabolism and cell injury decreased, although not reaching baseline. Histological examination revealed severe mucosal injury in all groups. There were no significant differences between groups in the observed parameters. No protective preconditioning response could be observed when performing repeated brief intestinal ischemic insults or repeated lung RMs before an intestinal I/R injury.
|
|
| 4. |
- Gordh, Torsten E, et al.
(författare)
-
Gabapentin in traumatic nerve injury pain : a randomized, double-blind, placebo-controlled, cross-over, multi-center study
- 2008
-
Ingår i: Pain. - : Ovid Technologies (Wolters Kluwer Health). - 0304-3959 .- 1872-6623. ; 138:2, s. 255-266
-
Tidskriftsartikel (refereegranskat)abstract
- A double-blind, randomized, placebo-controlled cross-over multi-center study was conducted to evaluate the efficacy and safety of gabapentin in the treatment of neuropathic pain caused by traumatic or postsurgical peripheral nerve injury, using doses up to 2400 mg/day. The study comprised a run-in period of two weeks, two treatment periods of five weeks separated by a three weeks' washout period. The primary efficacy variable was the change in the mean pain intensity score from baseline to the last week of treatment. Other variables included pain relief, health related quality of life (SF-36), interference of sleep by pain, Clinician and Patient Global Impression of Change, and adverse effects. Nine centers randomized a total of 120 patients, 22 of whom withdrew. There was no statistically significant difference between the treatments for the primary outcome efficacy variable. However, gabapentin provided significantly better pain relief (p=0.015) compared with placebo. More patients had at least a 30% pain reduction with gabapentin compared with placebo (p=0.040) and pain interfered significantly less with sleep during gabapentin treatment compared with placebo (p=0.0016). Both the Patient (p=0.023) and Clinician (p=0.037) Global Impression of Change indicated a better response with gabapentin compared with placebo. Gabapentin was well tolerated. The most common adverse effects were dizziness and tiredness.
|
|
| 5. |
|
|
| 6. |
- Haney, Michael, et al.
(författare)
-
Beat-to-beat change in "myocardial performance index" related to load.
- 2007
-
Ingår i: Acta Anaesthesiol Scand. - : Wiley. - 0001-5172 .- 1399-6576. ; 51:5, s. 545-52
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: This study was designed to assess the relationship of the "myocardial performance index" (MPI) to the beat-by-beat change in pre-load with static or unchanged contractile status. METHODS: Eight anesthetized juvenile pigs were studied using direct measurement of the left ventricular pressure and volume. Transient inflation of a vena cava balloon catheter produced controlled pre-load alterations. Consecutive beats were analyzed, grouped for first, second, third, etc. during the pre-load alteration, and evaluated for the change in MPI during the same contractile status with a controlled pre-load alteration. Two pharmacologic inotropic interventions were also included to generate several myocardial conditions in each animal. RESULTS: MPI demonstrated a strong linear relationship to the pre-load and after-load. MPI increased progressively during decreasing end-diastolic volume, mostly related to changes in ejection time. MPI was observed at the same level for three different myocardial function conditions (all eight animals), with a different relationship between MPI and pre-load noted for each observation. CONCLUSIONS: MPI is strongly load dependent, and can vary widely in value for the same contractile status if the load is varied. The use of this index in critically ill patients should be limited in this respect. Further work is needed to establish the relationship of MPI to load and contractile status.
|
|
| 7. |
- Haney, Michael F, et al.
(författare)
-
Myocardial systolic function increases during positive pressure lung inflation.
- 2005
-
Ingår i: Anesth Analg. - 0003-2999. ; 101:5, s. 1269-74
-
Tidskriftsartikel (refereegranskat)abstract
- Lung inflation with positive airway pressure may have rapid and dynamic effects on myocardial contractile function. We designed this study to assess the magnitude and time to onset of myocardial function changes during the initiation of single positive pressure lung inflation at clinically relevant inflation pressures. In 8 anesthetized 40-kg pigs, left ventricular pressures and volumes were measured directly (conductance volumetry). A 15 cm H2O airway pressure plateau with lung inflation (PPLI-15) was performed, and 2 single beats from that sequence, one from resting apnea at zero airway pressure and the second from the point when the lungs were first maximally inflated, were selected for analysis. Systolic function variables for zero airway pressure and PPLI-15 were analyzed. Systolic elastance, derived from bilinear time-varying elastance curves, increased approximately 15% during PPLI-15 from zero airway pressure. This agreed with other systolic function variables that identified an increase in left ventricular contractile function for the lung inflation beat. Serial measurements of myocardial function should be conducted with constant airway pressure and lung inflation conditions.
|
|
| 8. |
- Haney, Michael F, et al.
(författare)
-
The effect of lung inflation on absolute ventricular volume measurement by conductance.
- 2006
-
Ingår i: Clin Physiol Funct Imaging. - 1475-0961. ; 26:4, s. 220-3
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Conductance catheter in vivo ventricular volume measurements during lung ventilation may provide important information on left ventricular (LV) function. Breathing potentially may alter parallel conductance (V(c)), complicating interpretation of the conductance-derived volume signals. The effects of controlled positive pressure lung inflation (PPLI) on measured parallel conductance with dual-field conductance volumetry were investigated. METHODS: Eight anaesthetized pigs were instrumented with an LV dual-field conductance volumetry catheter. V(c) was measured repeatedly, using the hypertonic saline injection method, at three different levels of lung insufflation: continuous positive airway pressure (PPLI) 0, 5, and 10 cm H(2)O. RESULTS: V(c)s measured at PPLI 0, 5 and 10 cm H(2)O were 70.9 +/- 4.8, 70.7 +/- 5.5 and 70.5 +/- 5.9 ml, respectively. The corresponding uncalibrated end-diastolic volumes (EDV(u)) were 115.5 +/- 7.1, 117.0 +/- 7.5 and 117.5 +/- 7.7 ml, respectively. Mean coefficients of variance for V(c) and EDV(u) at all three PPLI levels were 3.8% and 1.25%, respectively. DISCUSSION: Several levels of PPLI demonstrated no systematic change in parallel conductance for LV dual-field conductance volume signal. We concluded that lung inflation at these levels does not generate changes in V(c).
|
|
| 9. |
- Häggmark, Sören, et al.
(författare)
-
Vectorcardiographic ST deviations related to increased heart rate in the absence of ischemia in an experimental pig model.
- 2006
-
Ingår i: J Electrocardiol. - : Elsevier BV. - 0022-0736 .- 1532-8430. ; 39:2, s. 169-76
-
Tidskriftsartikel (refereegranskat)abstract
- The electrocardiographic ST segment may change when heart rate (HR) increases. We aimed to analyze vectorcardiographic ST relation and myocardial conditions during controlled HR increases in anesthetized pigs. The relative parameters ST change vector magnitude and ST change vector angle were calculated at paced HRs ranging from 85 to 175 beats per minute. ST change vector magnitude increased from baseline 6.3 +/- 1.3 to 26.0 +/- 3.1 microV (P < .01; range, 4-50 microV) at HR 175 beats per minute with similar changes in ST change vector angle, whereas the absolute parameter ST vector magnitude demonstrated a heterogeneous pattern without any systematic relation to HR changes. Microdialysis results from left ventricular wall, with analysis of glucose, lactate, and pyruvate, showed no sign of ischemia during pacing. Potassium concentrations did not change during pacing. We conclude that significant HR-related ST vector changes can occur in the absence of myocardial ischemia.
|
|
| 10. |
- Konrad, D, et al.
(författare)
-
Positive inotropic and negative lusitropic effects of endothelin receptor agonism in vivo.
- 2005
-
Ingår i: Am J Physiol Heart Circ Physiol. - : American Physiological Society. - 0363-6135 .- 1522-1539. ; 289:4
-
Tidskriftsartikel (refereegranskat)abstract
- The endothelin (ET) system is involved in the regulation of myocardial function in health as well as in several diseases, such as congestive heart failure, myocardial infarction, and septic myocardial depression. Conflicting results have been reported regarding the acute contractile properties of ET-1. We therefore investigated the effects of intracoronary infusions of ET-1 and of the selective ET(B) receptor-selective agonist sarafotoxin 6c with increasing doses in anesthetized pigs. Myocardial effects were measured through analysis of the left ventricular pressure-volume relationship. ET-1 elicited increases in the myocardial contractile status (end-systolic elastance value of 0.94 +/- 0.11 to 1.48 +/- 0.23 and preload recruitable stroke work value of 68.7 +/- 4.7 to 83.4 +/- 7.2) that appear to be mediated through ET(A) receptors, whereas impairment in left ventricular isovolumic relaxation (tau = 41.5 +/- 1.4 to 58.1 +/- 5.0 and t(1/2) = 23.0 +/- 0.7 to 30.9 +/- 2.6, where tau is the time constant for pressure decay and t(1/2) is the half-time for pressure decay) was ET(B) receptor dependent. In addition, intravenous administration of ET-1 impaired ventricular relaxation but had no effect on contractility. Intracoronary sarafotoxin 6c administration caused impairments in left ventricular relaxation (tau from 43.3 +/- 1.8 to 54.4 +/- 3.4) as well as coronary vasoconstriction. In conclusion, ET-1 elicits positive inotropic and negative lusitropic myocardial effects in a pig model, possibly resulting from ET(A) and ET(B) receptor activation, respectively.
|
|
