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D Acolet

Publications and source records attributed to D Acolet.

14 recordsLinked to original sources
PubMed2001

Twenty-four hours of mild hypothermia in unsedated newborn pigs starting after a severe global hypoxic-ischemic insult is not neuroprotective.

Three to 12 h of mild hypothermia (HT) starting after hypoxia-ischemia is neuroprotective in piglets that are anesthetized during HT. Newborn infants suffering from neonatal encephalopathy often ventilate spontaneously and are not necessarily sedated. We aimed to test whether mild posthypoxic HT lasting 24 h was neuroprotective if the animals were not sedated. Thirty-nine piglets (median weight 1.6 kg, range 0.8-2.2 kg; median age 24 h, range 7-48 h) were anesthetized and ventilated and subjected to a 45-min hypoxic (FiO(2) approximately 6%) global insult (n = 36) or sham hypoxia (n = 3). On reoxygenation, 18 were maintained normothermic (NT, 39.0 degrees C) for 72 h, and 21 were cooled from 39 (NT) to 35 degrees C (HT) for the first 24 h before NT was resumed (18 experimental, three sham hypoxia). Cardiovascular parameters and intermittent EEG were documented throughout. The brain was perfusion fixed for neuropathology and five main areas examined using light microscopy. The insult severity (duration in minutes of EEG amplitude < 7 microV) was similar in the NT and HT groups, mean +/- SD (28 +/- 7.2 versus 27 +/- 8.6 min), as was the mean FiO(2) (5.9 +/- 0.7 versus 5.8 +/- 0.8%) during the insult. Six NT and seven HT piglets developed posthypoxic seizures that lasted 29 and 30% of the time, respectively. The distribution and degree of injury (0.0-4.0, normal-maximal damage) within the brain (hippocampus, cortex/white matter, cerebellum, basal ganglia, thalamus) were similar in the NT and HT groups (overall score, mean +/- SD, 2.3 +/- 1.5 versus 2.4 +/- 1.3) as was the EEG background amplitude at 3 h (13 +/- 3.5 versus 10 +/- 3.3 microV). The HT animals shivered and were more active. The sham control group (n = 3) shivered but had normal physiology and neuropathology. Plasma cortisol was significantly higher in the HT group during the HT period, 766 +/- 277 versus 244 +/- 144 microM at 24 h. Mild postinsult HT for 24 h was not neuroprotective in unsedated piglets and did not reduce the number of animals that developed posthypoxic seizures. Cortisol reached 3 times the NT value at the end of HT. We speculate that the stress of shivering and feeling cold interfered with the previously shown neuroprotective effect of HT. Research on the appropriateness of sedation during clinical HT is urgent.

Adult↗
PubMed1999

Prediction of neurological outcome after birth asphyxia from early continuous two-channel electroencephalography.

OBJECTIVE: To determine whether two-channel continuous electroencephalography (EEG) applied within 12 h of birth can predict the severity of neurological complications and neurodevelopmental outcome following birth asphyxia. METHODS: A continuous two-channel EEG was performed within 12 h of birth in 22 infants suspected of having suffered birth asphyxia and 11 healthy control infants (22 infants at a general and 11 at a specialist paediatric unit). Criteria to categorise normal and abnormal EEG records were defined and compared with the severity of hypoxic/ischaemic encephalopathy (HIE) and with neurodevelopmental outcome, assessed at or after 12 months of age. RESULTS: EEG recordings were commenced at a median (range) of 2 h 50 min (1 h 45 min to 12 h) after birth. Technically satisfactory recordings were obtained in all but one infant. All control infants remained asymptomatic and had a normal EEG with discernible sleep/awake periods. 12 h after birth the EEG was normal in all 12 infants suspected of asphyxia who remained well or developed grade 1 HIE and was abnormal in six of nine infants with grade II or III HIE. Fifteen of 16 infants suspected of asphyxia with a normal neurodevelopmental outcome had a normal EEG at 12 h; transient abnormalities lasting not more than 8 h had been detected in three of these infants. All five infants who died or developed neurodevelopmental abnormalities had an abnormal EEG. At 12 h of age the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and likelihood ratio for predicting severe (grade II or III) HIE were: 67, 100, 100, 80% and infinity and for subsequent death or neurodevelopmental impairments: 100, 94, 83, 100 and 16%, respectively. Assessment of the EEG before 12 h of age altered prognostic accuracy: 4 h after birth the sensitivity, specificity, positive and negative predictive values and the likelihood ratio for poor neurodevelopmental outcome were 100, 71, 33%, 100 and 3.7%, respectively (16 infants). CONCLUSION: Continuous two-channel EEG is an accurate tool for assessing the severity of neurological insult soon after birth asphyxia.

Asphyxia Neonatorum↗
PubMed1996

Phase I study of intraventricular recombinant tissue plasminogen activator for treatment of posthaemorrhagic hydrocephalus.

AIM: Phase I study to evaluate intraventricular fibrinolytic treatment with recombinant tissue plasminogen activator (tPA) as a method of clearing blood from the cerebrospinal fluid, and thus preventing permanent hydrocephalus. METHODS: Twenty two preterm infants, aged 7 to 26 days, with progressive posthaemorrhagic ventricular dilatation (ventricular width > 4 mm over 97th centile) received one to five intraventricular bolus injections of 1.0 mg or 0.5 mg tPA at intervals of one to seven days. RESULTS: The mean cerebrospinal fluid concentration of tPA 24 hours after 1 mg was 1860 micrograms/ml. The half life of tPA in cerebrospinal fluid was about 24 hours. Twenty one (95%) infants survived, 12 (55%) without shunt surgery. One infant had secondary intraventricular haemorrhage. CONCLUSION: Intraventricular tPA resulted in survival without a shunt for most of the infants, but with some risk. Failure may have been due to plasminogen deficiency, an inhibitor, or late intervention.

Cerebral Hemorrhage↗
PubMed1995

Ischaemic and haemorrhagic brain lesions in newborns with seizures and normal Apgar scores.

Serial ultrasound scans and conventional and diffusion weighted magnetic resonance imaging (MRI) were performed on 16 neonates who presented with seizures. The Apgar scores were normal and subsequently no metabolic or infective cause could be found. The aim of the study was to evaluate the extent to which early sequential imaging can elucidate the cause of seizures in apparently neurologically normal infants. Fourteen of the infants had haemorrhagic or ischaemic lesions on MRI and these were detected by ultrasound scanning in 11. Early ultrasound scanning detected the haemorrhagic lesions but the ischaemic lesions were often not seen until the end of the first week of life. Early MRI, however, was able to detect all the ischaemic lesions. The evolution of the insult could be timed by using serial ultrasound scans and a combination of diffusion weighted and conventional MRI during the first week of life, confirming a perinatal insult even in the absence of fetal distress. Although the aetiology of these lesions remains obscure, serial ultrasound scans will detect the presence of cerebral lesions in neonates presenting with isolated seizures but additional MRI sequences will give better definition on type, site, and extent of the pathology.

Apgar Score↗
PubMed1994

Enterobacter cloacae in a neonatal intensive care unit: account of an outbreak and its relationship to use of third generation cephalosporins.

After uneventful use of cefotaxime and ceftazidime as first line therapy for three years in our neonatal intensive care unit we isolated cephalosporin-resistant Enterobacter cloacae (CREC) strains which caused clusters of cases or colonization and/or serious neonatal infection. By using two or more typing methods, at least five different strains with similar patterns of antimicrobial sensitivities were identified. The results of a case-control study did not support the notion that the use of third generation cephalosporins was associated with colonization and infection by CREC. The outbreak was brought under control by interrupting the transmission of the epidemic strain D, by measures such as cohort nursing, diligent handwashing before and after procedures, and thorough environmental cleaning as well as by decontamination with glutaraldehyde after dismantling of the blood gas analyser believed to have acted as a persistent reservoir. Our experience highlights the danger of inadequate supervision and maintenance of equipment used for near-patient testing and the need to monitor such equipment not only in terms of its calibration and analytical performance but also microbiologically.

Blood Gas Analysis↗
PubMed1994

Evolution of early hemiplegic signs in full-term infants with unilateral brain lesions in the neonatal period: a prospective study.

Neonates with unilateral hemispheric lesions detected by imaging in the newborn period are at risk for developing hemiplegia. Five full-term infants with predominantly unilateral lesions identified by cranial ultrasound in the neonatal period and confirmed with MRI were examined clinically at regular intervals in order to establish the development, incidence and evolution of later hemiplegia and the evolution of hemiplegic signs. In the neonatal period the infants had either a normal examination or subtle transient abnormalities. Abnormalities were not seen until 6 months of age in infants who developed hemiplegia. The number of hemiplegic signs in each child increased with time, the earlier the signs appeared the more severe the hemiplegia. In some infants deterioration with loss of preexisting skills was observed. At 24 months two of the infants were normal, one had a mild and two a moderate hemiplegia.

Brain Damage, Chronic↗
PubMed1994

Prognostic value of continuous electroencephalographic recording in full term infants with hypoxic ischaemic encephalopathy.

The prognostic value of early neonatal continuous electroencephalographic recordings in hypoxic ischaemic encephalopathy was evaluated. Thirty seven full term infants with hypoxic ischaemic encephalopathy were studied. The electroencephalogram (EEG) was recorded using four or eight channel Oxford Medilog recorders and was started as soon as possible after birth. The recordings were initially visually analysed and divided into four categories: three in relation to the grade of discontinuity of the background activity (continuous, discontinuous, and maximum depression) and an additional fourth category to include status epilepticus. The EEGs with discontinuous activity were then analysed by computer to obtain a more objective assessment of discontinuity. The results were related to neurological outcome. Continuous background activity was associated with a normal outcome in all but the three infants who had continuous, but asymmetrical EEGs and who developed contralateral hemiplegia. In the eight infants with discontinuous activity, the outcome appeared to be related to the grade of continuity and the presence of clear convulsions on the EEG. The 10 infants with maximum depression and status epilepticus had severe impairment. These preliminary results suggest that continuous recording of EEGs could be used routinely in term infants with hypoxic ischaemic encephalopathy. Computer analysis can improve the value of this technique, allowing the identification of infants who might benefit from early therapeutic intervention.

Brain Damage, Chronic↗
PubMed1994

Fetal marrow suppression after maternal chemotherapy for leukaemia.

A preterm baby, whose mother received chemotherapy for acute leukaemia during pregnancy, required intensive care because of profound anaemia and neutropenia. Haemopoietic progenitor cell studies showed fetal marrow suppression. Those caring for such mothers and babies should know the possible serious effects chemotherapy for malignancies can have on a developing fetus. Long term follow up of the baby is imperative.

Acute Disease↗
PubMed1993

Changes in plasma cortisol and catecholamine concentrations in response to massage in preterm infants.

The biochemical and clinical response to massage in preterm infants was assessed. Eleven stable infants, of 29 weeks' median gestational age, median birth weight 980 g, and median postnatal age 20 days, were studied. Blood samples were obtained for the determination of adrenaline, noradrenaline, and cortisol 45 minutes before the start of massage and approximately one hour after completion of massage. Cortisol, but not catecholamine, concentrations decreased consistently after massage (median difference -35.8 nmol/l; 95% confidence interval -0.5 to -94.0, Wilcoxon matched pairs). There was a slight decrease in skin temperature (median difference -0.36 degrees C, 95% confidence interval -0.09 to -0.65) but there was no change in oxygenation or oxygen requirement. This study has shown that it is possible to detect an objective hormonal change following a supposedly 'non-therapeutic' intervention in preterm infants. The development of such methods of assessment are likely to be of particular relevance in the extremely immature or ill neonate in whom behavioural evaluation cannot play more than a limited part.

Birth Weight↗
PubMed1989

Oxygenation, heart rate and temperature in very low birthweight infants during skin-to-skin contact with their mothers.

Fourteen very low birthweight infants were studied positioned either prone horizontal or skin-to-skin at 60 degree tilt between the mother's breasts. Heart rate, skin temperature and oxygenation by transcutaneous PO2 and pulse oximetry were measured. Nine of the infants had normal lungs when studied. These infants showed no change in tcPO2 or oxygen saturation but heart rate increased significantly by a mean of 6.5 beats per min during skin-to-skin contact. Five infants with chronic lung disease, including two on nasal catheter oxygen, showed a significant 1.0 kPa rise in tcPO2 during skin-to-skin contact. Back skin temperature was well maintained during skin-to-skin contact with the room temperature at 26 to 29 degrees C. None of the infants had a significant apnoea or bradycardia during the study. Stable very low birthweight infants can enjoy such close contact with their mothers and the tilted position may improve pulmonary function in some cases.

Blood Gas Monitoring, Transcutaneous↗
PubMed1988

Skin to skin contact for very low birthweight infants and their mothers.

Separation between mothers and very low birthweight infants is often prolonged with subsequent psychological distress, behaviour problems, and lactation failure. Babies as small as 700 g, who no longer require oxygen, can be safely and enjoyably held naked, except for a nappy, between the mother's breasts for up to four hours a day. We have carried out a randomised trial among babies less than 1500 g. Seventy one infants were randomised. In 35, the mother was helped to hold her baby in skin to skin contact and encouraged to do so whenever she visited the baby. In 36, the mother was encouraged to handle her baby but without skin to skin contact. Mothers using skin to skin contact lactated for four weeks longer on average than the control group. At 6 months of age the infants who had skin to skin contact cried significantly less than the control group. Skin to skin contact can safely and enjoyably be offered to very low birthweight infants especially in developing countries where the mother's lactation is vital.

Child Behavior↗