| 1. |
- Feet, B A, et al.
(författare)
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Early cerebral metabolic and electrophysiological recovery during controlled hypoxemic resuscitation in piglets
- 1998
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Ingår i: Journal of Applied Physiology. - 1522-1601. ; 84:4, s. 1208-1216
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Tidskriftsartikel (refereegranskat)abstract
- We tested the hypothesis that controlled hypoxemic resuscitation improves early cerebral metabolic and electrophysiological recovery in hypoxic newborn piglets. Severely hypoxic anesthetized piglets were randomly divided into three resuscitation groups: hypoxemic, 21% O2, and 100% O2 groups (8 in each group). The hypoxemic group was mechanically ventilated with 12-18% O2 adjusted to achieve a cerebral venous O2 saturation of 17-23% (baseline; 45 +/- 1%). Base excess (BE) reached -22 +/- 1 mM at the end of hypoxia. During a 2-h resuscitation period, no significant differences in time to recovery of electroencephalography (EEG), quality of EEG at recovery, or extracellular hypoxanthine concentrations in the cerebral cortex and striatum were found among the groups. BE and plasma hypoxanthine, however, normalized significantly more slowly during controlled hypoxemic resuscitation than during resuscitation with 21 or 100% O2. We conclude that early brain recovery during controlled hypoxemic resuscitation was as efficient as, but not superior to, recovery during resuscitation with 21 or 100% O2. The systemic metabolic recovery from hypoxia, however, was delayed during controlled hypoxemic resuscitation.
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| 2. |
- Greisen, G, et al.
(författare)
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EEG depression and germinal layer haemorrhage in the newborn
- 1987
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Ingår i: Acta Paediatrica Scandinavica. - : Wiley. - 0001-656X .- 0803-5253 .- 1651-2227. ; 76:3, s. 519-525
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Tidskriftsartikel (refereegranskat)abstract
- Amplitude integrated EEG (aEEG) recordings from 32 mechanically ventilated infants, gestational age 32 weeks or less, were analysed. All recordings were started within 24 h of birth and continued for at least 50 h. Germinal layer haemorrhage (GLH) was diagnosed by repeated ultrasonography. In six infants neither GLH nor hypocalcaemia were diagnosed; aEEG in these infants rapidly became more active after birth: at 30 h of age continuous background activity was present for more than 20% of the time, and a seizure-like pattern was exceptional. In seven infants without GLH but with hypocalcaemia and other signs of metabolic derangement, continuous background activity appeared later and seizure-like activity was frequent. In the infants with GLH, depression of the background activity was apparent. This finding was particularly distinct in the presence of severe haemorrhages. Four infants developed GLH after 30 h of age. All these infants had depressed aEEG before the development of GLH, with less than 20% continuous activity at 30 h of age. In ten infants an analysis of the aEEG during the occurrence of GLH was possible. In six of these, cortical electrical activity decreased. Due to the limitation of GLH timing, it was not possible to decide whether this decrease closely preceded or followed GLH. We suggest that GLH primarily occurs in brains with a preceding metabolic and neurophysiologic abnormality, and that further functional deterioration is caused by the most severe haemorrhages.
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| 3. |
- Hellström-Westas, Lena, et al.
(författare)
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Cerebral complications detected by EEG-monitoring during neonatal intensive care
- 1989
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Ingår i: Acta paediatrica Scandinavica. Supplement. - : Wiley. - 0300-8843. ; 78:S360, s. 83-86
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Tidskriftsartikel (refereegranskat)abstract
- The report describes the clinical use and value of continuous EEG-monitoring during different clinical circumstances that are not usually related to changes in EEG. Three infants with pneumothorax, hypoglycaemia, and severe hyaline membrane, respectively, are presented.
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| 4. |
- Hellström-Westas, Lena, et al.
(författare)
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Cerebral function monitoring during the first week of life in extremely small low birthweight (ESLBW) infants
- 1991
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Ingår i: Neuropediatrics. - 0174-304X. ; 22:1, s. 27-32
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Tidskriftsartikel (refereegranskat)abstract
- In order to evaluate the usefulness of early continuous EEG-monitoring in very preterm neonates, recordings with a Cerebral Function Monitor (CFM) were made prospectively in 31 ESLBW infants with birthweights below 901 grams, during their first week of life. The CFM background activity was, as expected from EEG studies, dominated by a suppression-burst pattern in 94% of the infants. Some infants had periods with more continuous EEG activity or suppression-burst changing into continuous. Patterns similar to sleep-wake cycling (SWC) were identified in infants with gestational ages as low as 24 weeks. The level of the CFM-background activity was mainly influenced by the presence and severity of intracranial hemorrhage (ICH), but also by medications such as phenobarbital. Epileptiform activity (EPA) was only found in infants with ICH, and was identified in 75% of these infants. Of the infants with EPA, 87% had periods with subclinical EPA, although 47% had both clinical and subclinical seizures. The presence of more continuous activity and SWC were indicators of a favourable outcome, whereas electrocerebral inactivity predicted an unfavorable outcome. The prognostic estimates of mortality and neurologic outcome were similar for early CFM recording (positive predictive value 69-100%) and cranial ultrasound scan (positive predictive value 71-100%). The monitoring of cerebral electrical activity also provided immediate and clinically useful information during the intensive care of these ESLBW infants. Further studies on the causal relation between EPA and the development of ICH should be performed before definite conclusions can be drawn concerning any preventive effect from anticonvulsive treatment of clinical/subclinical seizures.
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| 5. |
- Hellström-Westas, Lena, et al.
(författare)
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Cerebroelectrical depression following surfactant treatment in preterm neonates
- 1992
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Ingår i: Pediatrics. - 1098-4275. ; 89:4 Pt 1, s. 643-647
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Tidskriftsartikel (refereegranskat)abstract
- During surfactant treatment of respiratory distress syndrome, 23 premature newborns were investigated with continuous amplitude-integrated electroencephalography (cerebral function monitors). Simultaneously, arterial blood pressure and transcutaneous blood gas values were recorded. A short (less than 10 minutes) but significant decrease in cerebral activity was seen in almost all neonates immediately after the surfactant instillation, in spite of an improved pulmonary function. In 21 of 23 neonates, a transient fall in mean arterial blood pressure of 9.3 mm Hg (mean) occurred coincidently with the cerebral reaction. Neonates in whom intraventricular hemorrhage developed tended to have lower presurfactant mean arterial blood pressure (P greater than .05), but they had a significantly lower mean arterial blood pressure after surfactant instillation (P less than .05). No other differences were found between neonates in whom intraventricular hemorrhage developed and those without intraventricular hemorrhage. The present findings demonstrate that an acute cerebral dysfunction may occur after surfactant instillation. In some vulnerable neonates with arterial hypotension and severe pulmonary immaturity, the fall in mean arterial blood pressure may increase the risk of cerebral complications and could be related to an unchanged rate of intraventricular hemorrhage after surfactant treatment.
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| 6. |
- Hellström-Westas, Lena, et al.
(författare)
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Lidocaine for treatment of severe seizures in newborn infants. I. Clinical effects and cerebral electrical activity monitoring
- 1988
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Ingår i: Acta Paediatrica Scandinavica. - : Wiley. - 0001-656X .- 0803-5253 .- 1651-2227. ; 77:1, s. 79-84
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Tidskriftsartikel (refereegranskat)abstract
- The anticonvulsive effect of lidocaine was evaluated in 46 newborn infants with severe, recurrent seizures. Before the lidocaine all infants were being given phenobarbital, and 22 infants were also treated with diazepam. Different dosages of lidocaine were tested. A loading dose of 2 mg/kg followed by i.v. infusion of 6 mg/kg/hour was the most effective dosage and had an immediate anticonvulsive effect in 18 of 25 infants; within 30 min the same effect was attained in another five of the infants, with an overall seizure control in 92% of the sample population. During the lidocaine treatment cerebral electrical activity was followed continuously with a cerebral function monitor (CFM), which also enabled evaluation of the treatment. No serious side effects on blood-pressure, heart-rate or cerebral electrical activity were registered. For newborn infants with severe recurrent seizures not responding to other drugs, lidocaine is an effective additional mode of treatment.
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| 7. |
- Hellström-Westas, Lena, et al.
(författare)
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Lidocaine for treatment of severe seizures in newborn infants. II. Blood concentrations of lidocaine and metabolites during intravenous infusion
- 1992
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Ingår i: Acta Pædiatrica. - : Wiley. - 1651-2227 .- 0803-5253. ; 81:1, s. 35-39
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Tidskriftsartikel (refereegranskat)abstract
- The blood concentrations of lidocaine and its main active metabolites, methylethylglycinexylidide (MEGX) and glycinexylidide (GX), were measured in 24 newborn infants during anticonvulsive treatment with an iv infusion of lidocaine. After a bolus dose of 1.5-2.2 mg/kg and continuous infusion of lidocaine (4.7-6.3 mg/kg/h) there was accumulation of the drug and MEGX within 24 h. After termination of the iv infusion, both lidocaine and the metabolites were eliminated within 24-48 h. The anticonvulsive effectiveness--estimated by clinical observation and continuous amplitude integrated EEG monitoring (cerebral function monitor)--was immediate in 15 infants (nine term and six preterm). There was no correlation between blood concentrations of lidocaine and metabolites, and anticonvulsive effect (i.e. good, intermediate or no response). No differences in blood concentrations were found between full-term and preterm babies, or between infants with or without birth asphyxia. In combination with a fast withdrawal of the drug, few adverse reactions were seen with the dosages used, even though blood concentrations were high. Routine measurements of lidocaine concentrations during anticonvulsive treatment in neonates seem to be of little clinical value. For evaluation of the anticonvulsive effect and for early detection of seizure activity during lidocaine withdrawal, continuous EEG monitoring is preferable.
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| 8. |
- Hellström-Westas, Lena, et al.
(författare)
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Low risk of seizure recurrence after early withdrawal of antiepileptic treatment in the neonatal period
- 1995
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Ingår i: Archives of disease in childhood. Fetal and neonatal edition. - 1359-2998. ; 72:2, s. 97-101
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Tidskriftsartikel (refereegranskat)abstract
- The risk of seizure recurrence within the first year of life was evaluated in infants with neonatal seizures diagnosed with a combination of clinical signs, amplitude-integrated electroencephalogram (EEG) monitoring, and standard EEG. Fifty eight of 283 (4.5%) neonates in tertiary level neonatal intensive care had seizures. The mortality in the infants with neonatal seizures was 36.2%. In 31 surviving infants antiepileptic treatment was discontinued after one to 65 days (median 4.5 days). Three infants received no antiepileptic treatment, two continued with prophylactic antiepileptic treatment. Seizure recurrence was present in only three cases (8.3%)--one infant receiving prophylaxis, one treated for 65 days, and in one infant treated for six days. Owing to the small number of infants with seizure recurrence, no clinical features could be specifically related to an increased risk of subsequent seizures. When administering antiepileptic treatment, one aim was to abolish both clinical and electrographical seizures. Another goal was to minimise the duration of treatment and to keep the treatment as short as possible. It is suggested that treating neonatal seizures in this way may not only reduce the risk of subsequent seizure recurrence, but may also minimise unnecessary non-specific prophylactic treatment for epilepsy.
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| 9. |
- Hellström-Westas, Lena, et al.
(författare)
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Predictive value of early continuous amplitude integrated EEG recordings on outcome after severe birth asphyxia in full term infants
- 1995
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Ingår i: Archives of disease in childhood. Fetal and neonatal edition. - 1359-2998. ; 72:1, s. 34-38
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Tidskriftsartikel (refereegranskat)abstract
- The background pattern in single channel amplitude integrated EEG recordings (aEEG) was recorded in 47 infants within the first six hours after birth to see if this could predict outcome after birth asphyxia. The aEEG background pattern during the first six hours of life was continuous and of normal voltage in 26 infants. All these infants survived; 25 were healthy, one had delayed psychomotor development. A continuous but extremely low voltage pattern was present in two infants, both of whom survived with severe handicap. Five infants had flat (mainly isoelectric) tracings during the first six hours of life; four died in the neonatal period, and one survived with severe neurological handicap. Burst-suppression pattern was identified in 14 infants, of whom five died, six survived with severe handicap, and three were healthy at follow up. The type of background pattern recorded within the first six postnatal hours in the aEEG tracings predicted outcome correctly in 43 of 47 (91.5%) infants. Use of aEEG monitoring can predict outcome, with a high degree of accuracy, after birth asphyxia, within the first six hours after birth. The predictive value of a suppression-burst pattern was, however, somewhat lower than the other background patterns. The aEEG seems to be a feasible technique for identifying infants at high risk of subsequent brain damage who might benefit from interventionist treatment after asphyxia.
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| 10. |
- Skov, L, et al.
(författare)
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Acute changes in cerebral oxygenation and cerebral blood volume in preterm infants during surfactant treatment
- 1992
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Ingår i: Neuropediatrics. - 0174-304X. ; 23:3, s. 126-130
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Tidskriftsartikel (refereegranskat)abstract
- Following administration of surfactant a marked depression in aEEG activity occurs for about 10 minutes; the mechanism of this depression is unknown. In view of this, twenty-nine preterm infants were investigated with near infrared spectroscopy (NIRS) to evaluate rapid changes in total cerebral haemoglobin concentration and cerebral oxyhaemoglobin concentration during rescue treatment with natural surfactant. During surfactant instillation there was a short-lasting hypoxaemia as demonstrated by pulseoximetry as well as a considerable fall in arterial blood pressure. With NIRS, tissue hypoxia was demonstrated by a drop in cerebral oxyhaemoglobin concentration. The marked drop in arterial blood pressure occurring immediately following surfactant was not matched by a drop in total cerebral haemoglobin concentration. This suggests that cerebral blood volume and hence cerebral blood flow was maintained. In the following minutes there was an improvement in cerebral oxygenation as indicated by the rise in cerebral oxyhaemoglobin concentration in nearly all the infants.
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