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P Steer

Publications and source records attributed to P Steer.

At least 19 recordsLinked to original sources

National census of availability of neonatal intensive care. British Association for Perinatal Medicine.

OBJECTIVE: To determine whether availability of neonatal intensive care cots is a problem in any or all parts of the United Kingdom. DESIGN: Three month census from 1 April to 30 June 1999 comprising simple data sheets on transfers out of tertiary units. SETTING: The 37 largest high risk perinatal centres in the United Kingdom. PARTICIPANTS: One obstetric specialist and one neonatal specialist in each centre. MAIN OUTCOME MEASURES: Suboptimal care resulting directly from pressure on service-that is, transfers out of tertiary units (either in utero or after delivery) because the unit was "full" and not because the hospital was incapable of providing the care needed. RESULTS: All units provided data. The number of intensive care cots in each unit was between five and 16. During the three months 309 transfers occurred (equivalent to 1236 per year), of which 264 were in utero and 45 postnatal. Sixty five in utero transfers involved multiple births, hence the census related to 382 babies (1528 per year). There was considerable regional variation. The reason for transfer in most cases was "lack of neonatal beds". CONCLUSIONS: Currently most major perinatal centres in the United Kingdom are regularly unable to meet in-house demand; this has implications for the service as a whole. The NHS has set no standards to help health authorities and primary care groups develop services relating to this specialty; such a step may well be an appropriate lever for change.

Bed Occupancy↗

Postoperative caffeine for preventing apnea in preterm infants.

BACKGROUND: Growing ex-preterm infants who undergo general anesthesia for surgery at about term-equivalent age may have episodes of apnea, cyanosis and bradycardia during the early postoperative period. Caffeine treatment given at the time of operation might prevent these episodes. OBJECTIVES: In ex-preterm infants who undergo general anesthesia for surgery, does the prophylactic use of caffeine prevent episodes of apnea, cyanosis and bradycardia during the postoperative period without clinically important side effects? SEARCH STRATEGY: The standard strategy of the Neonatal Review Group was used. This included searches of the Oxford Database of Perinatal trials, Medline, previous reviews including cross references, abstracts, conferences and symposia proceedings, expert informants and journal handsearching mainly in the English language. SELECTION CRITERIA: All trials utilising random or quasi-random patient allocation, in which treatment was compared with placebo or no treatment, were included. DATA COLLECTION AND ANALYSIS: The standard methods of the Cochrane Collaboration and its Neonatal Review Group were used to select trials, evaluate quality and to extract data. The methodological quality of each trial was reviewed by the second author blinded to trial authors and institution(s). Each author extracted data separately, compared and resolved differences. Meta-analysis used relative risk and risk difference. MAIN RESULTS: In each trial apnea/bradycardia occurred in fewer treated than control infants. In two trials (Welborn 1989, LeBard 1989) continuous recordings of oxygen saturation detected hypoxaemic episodes (<90 %) in fewer treatment than control infants. No infant in any trial required intubation and mechanical ventilation. No adverse effects were reported. REVIEWER'S CONCLUSIONS: Implications for practice. Caffeine can be used to prevent postoperative apnea/bradycardia and episodes of oxygen desaturation in growing preterm infants if this is deemed clinically necessary. In view of the small numbers of infants studied in these trials and uncertainty concerning the clinical significance of the episodes, caution is warranted in applying these results to routine clinical practice. Implications for research. There is a need to determine which infants might benefit most by this treatment. Studies confined to those most at risk of apnea (prior history, younger postmenstrual age) and those that might require mechanical ventilation (chronic lung disease) would be of value.

Anesthesia, General↗

Doxapram versus methylxanthine for apnea in preterm infants.

BACKGROUND: Recurrent apnea is common in preterm infants, particularly at very early gestational ages. These episodes of loss of effective breathing can lead to hypoxemia and bradycardia which may be severe enough to require resuscitation including use of positive pressure ventilation. Doxapram and methylxanthine drugs have been used to stimulate breathing and so prevent apnea and its consequences. OBJECTIVES: In preterm infants with recurrent apnea, how does treatment with doxapram compare with treatment with theophylline in leading to a clinically important reduction in apnea and use of mechanical ventilation, without clinically important side effects. SEARCH STRATEGY: The standard search strategy of the Neonatal Review Group, as outlined in the Cochrane Library, was used. SELECTION CRITERIA: All trials utilising random or quasi-random patient allocation, in which doxapram was compared with methylxanthine (e.g. theophylline) for the treatment of apnea, were eligible. There must have been an effort to exclude specific causes of apnea. DATA COLLECTION AND ANALYSIS: The standard methods of the Cochrane Collaboration and its Neonatal Review Group were used to select trials, assess quality and to extract and synthesize data. The methodological quality of each trial was reviewed by the second author blinded to trial authors and institution(s). Additional information was requested from authors to clarify methodology. Each author extracted the data separately, then they were compared and differences resolved. Meta-analysis was carried out with use of relative risk and risk difference. MAIN RESULTS: In these trials involving a relatively small number of preterm infants with apnea of prematurity, there is no apparent difference between the effect of intravenous treatment with doxapram or methylxanthine on the incidence of apnea within 48 hours. There were no infants reported to have been given mechanical ventilation on either treatment. No adverse effects were reported. REVIEWER'S CONCLUSIONS: Implications for practice. The overall results of these small trials suggest that intravenous doxapram and intravenous methylxanthine are not different in their effectiveness in the short term in the treatment of apnea of prematurity. Caution is warranted as the number of patients in these trials is too small to exclude an important difference between these two treatments or to exclude the possibility of less common side effects. Longer term outcome of infants treated in these trials has not been reported. Implications for research. Further studies would require a large number of infants, stratified by gestation, to clarify which infants are likely to benefit and whether there might be differences in responses or side effects with these two drugs at different ages. It would be valuable to include important clinical outcomes such as use of mechanical ventilation as well as subsequent growth and development in future studies. Responses to treatment would have to take account of co-interventions, such as nasal continuous airway pressure which is frequently used post-intubation.

Aminophylline↗

Methylxanthine treatment for apnea in preterm infants.

BACKGROUND: Recurrent apnea is common in preterm infants, particularly at very early gestational ages. These episodes of loss of effective breathing can lead to hypoxemia and bradycardia which may be severe enough to require resuscitation including use of positive pressure ventilation. Methylxanthines have been used to stimulate breathing and prevent apnea and its consequences. OBJECTIVES: The objective of this review is to determine if methylxanthine treatment in preterm infants with recurrent apnea leads to a clinically important reduction in apnea and use of intermittent positive pressure ventilation (IPPV), without clinically important side effects. SEARCH STRATEGY: Searches were made of the Oxford Database of Perinatal Trials, MEDLINE, EMBASE, previous reviews including cross references, abstracts of conferences and symposia proceedings, expert informants, journal handsearching mainly in the English language. SELECTION CRITERIA: All trials utilising random or quasi-random patient allocation, in which methylxanthine (theophylline or caffeine) was compared with placebo or no treatment for apnea in preterm infants, were included. DATA COLLECTION AND ANALYSIS: Methodological quality was assessed independently by the two authors. Data were extracted independently by the two authors. Treatment effects were expressed as relative risk (RR) and risk difference (RD) and their 95% confidence intervals, using a fixed effect model. For significant results, the inverse of the risk difference (1/RD) was used to calculate the number needed to treat (NNT). MAIN RESULTS: The results of four trials which enrolled a total of 110 preterm infants with apnea indicate that methylxanthine therapy leads to a reduction in apnea and use of IPPV in the first 2 - 7 days. There are insufficient data to evaluate side effects and no data to examine effects within different gestational age groups. There are no trial data which examine long term effects. REVIEWER'S CONCLUSIONS: Methylxanthines are effective in reducing the number of apneic attacks and the use of mechanical ventilation in the two to seven days after starting treatment. In view of its lower toxicity, caffeine would be the preferred drug. Although the safety of methylxanthine therapy has been suggested in cohort studies, there are no trial data on longterm outcome. In order to indicate which infants are likely to benefit from treatment, there is a need for stratification by gestation and/or other risk factors in future studies. In any future studies the longer term effects of treatment on growth and development should be evaluated.

Apnea↗

Glucose production by the human placenta in vivo.

The human placenta transports glucose by facilitated diffusion down a concentration gradient from mother to fetus. It has previously been considered incapable of glucose synthesis. However, recent work has demonstrated the presence in placental tissue of glucose-6-phosphatase, which is required for the final step in the synthesis of glucose. Following continuous intravenous infusion into the maternal circulation of the stable isotope, 6,6-(2)H(2)glucose, during elective caesarean section, we have observed isotope dilution in the umbilical vein, without further dilution in the umbilical artery. Using a mathematical model containing maternal, placental and fetal compartments, the data were compatible with the release of glucose by the placenta. We conclude that the human placenta at term can produce glucose.

Adult↗

Fetal growth.

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Animals↗

Gender does not affect fetal heart rate variation.

There is a widespread but erroneous view among the lay public that there is a difference in the baseline fetal heart rate between male and female fetuses. It has been suggested that this perception might reflect an actual difference in fetal heart rate variability. Therefore, we studied the fetal heart rate variation in 79 white European women using the Sonicaid System 8002 computer. Fourty-four of the fetuses were male and 35 were female. There was no significant gender difference in any measured aspect of fetal heart rate variation.

Adult↗