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Current intensive care ventilator-humidifier systems neither monitor nor adequately control inspired gas humidity. Problems of low delivered humidity and condensation within ventilator circuitry are commonly encountered. To help to address these problems, a numerical model of a complete ventilator-humidifier-patient intensive care system has been developed. The model, based on a finite difference technique, can predict pressures, flow-rates, temperatures and relative humidities at discrete points throughout the system. A comparison of numerical predictions and measurements in a real system is reported. A strong qualitative agreement is demonstrated in all cases studied, and a good quantitative agreement is obtained in most cases. It is concluded that such models could be used to assess methods of controlling ventilator-humidifier systems to prevent the occurrence of condensation. Similar models could be developed for other medical gas delivery systems.

Newborn animal and human pilot studies suggest that mild hypothermia following peripartum hypoxia-ischaemia in newborn infants may reduce neurological sequelae, without adverse effects.To determine whether therapeutic hypothermia in encephalopathic asphyxiated newborn infants reduces mortality and long-term neurodevelopmental disability, without clinically important side effects.The standard search strategy of the Neonatal Review Group as outlined in the Cochrane Library (Issue 2, 2003) was used. Randomised controlled trials evaluating therapeutic hypothermia in term newborns with hypoxic ischaemic encephalopathy were identified by searching the Oxford Database of Perinatal Trials, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library Issue Issue 2, 2003), MEDLINE (1966 to July 2003), previous reviews including cross-references, abstracts, conferences, symposia proceedings, expert informants and journal hand searching.Randomised controlled trials comparing the use of therapeutic hypothermia with normothermia in encephalopathic newborn infants with evidence of peripartum asphyxia and without recognisable major congenital anomalies were included. The primary outcome measure was death or long-term major neurodevelopmental disability. Other outcomes included adverse effects of cooling and 'early' indicators of neurodevelopmental outcome.Three reviewers independently selected, assessed the quality of and extracted data from the included studies. Authors were contacted for further information. Meta-analyses were performed using relative risk and risk difference for dichotomous data, and weighted mean difference for continuous data with 95% confidence intervals.Two randomised controlled trials were included in this review, comprising 50 term infants with moderate/ severe encephalopathy and evidence of intrapartum asphyxia. There was no significant effect of therapeutic hypothermia on the combined outcome of death or major neurodevelopmental disability in survivors followed. No adverse effects of hypothermia on short term medical outcomes or on some 'early' indicators of neurodevelopmental outcome were detected.Although two small randomised controlled trials demonstrated neither evidence of benefit or harm, current evidence is inadequate to assess either safety or efficacy of therapeutic hypothermia in newborn infants with hypoxic ischaemic encephalopathy. Therapeutic hypothermia for encephalopathic asphyxiated newborn infants should be further evaluated in well designed randomised controlled trials.

Preterm birth after spontaneous preterm labour is associated with death, neonatal disease, and long-term disability. Previous small trials of antibiotics for spontaneous preterm labour have reported inconclusive results. We did a randomised multicentre trial to resolve this issue.6295 women in spontaneous preterm labour with intact membranes and without evidence of clinical infection were randomly assigned 250 mg erythromycin (n=1611), 325 mg co-amoxiclav (250 mg amoxicillin and 125 mg clavulanic acid; n=1550), both (n=1565), or placebo (n=1569) four times daily for 10 days or until delivery, whichever occurred earlier. The primary outcome measure was a composite of neonatal death, chronic lung disease, or major cerebral abnormality on ultrasonography before discharge from hospital. Analysis was by intention to treat.None of the trial antibiotics was associated with a lower rate of the composite primary outcome than placebo (erythromycin 90 [5.6%], co-amoxiclav 76 [5.0%], both antibiotics 91 [5.9%], vs placebo 78 [5.0%]). However, antibiotic prescription was associated with a lower occurrence of maternal infection.This trial provides evidence that antibiotics should not be routinely prescribed for women in spontaneous preterm labour without evidence of clinical infection.

A census of activity and staff levels in 1996 was conducted in UK neonatal units and achieved a 100% response from 246 units. Among the 186 neonatal intensive care units, the median (interquartile range) number of total cots was 18(14−22); level 1 intensive care cots 4(2−6); total admissions 318(262−405); very low birthweight admissions 40(28−68); and the number ventilated or given CPAP by endotracheal tube 52(32−83). Forty six (25%) intensive care units lacked the recommended minimum of one consultant with prime responsibility for neonatal medicine. As a conservative estimate 79% of intensive care units had a lower nursing provision than that recommended in previously published guidelines. There was substantial variation in activity and staffing levels among units.

In their detailed study of the long-term survivors of bronchopulmonary dysplasia (BPD) Smyth and colleagues1 contrast their findings of a high incidence of abnormal pulmonary function in early childhood with the commonly held view that pulmonary function becomes normal in most children surviving BPD.2 However, they do not give us detailed parameters of the mode of intermittent positive pressure ventilation (IPPV) used on their patients, in particular maximum peak pressures, inspiratory: expiratory ratios and rates, or type of pressure wave curves generated by the ventilators used.