Persistent patent ductus arteriosus (PDA) is associated with mortality and morbidity in preterm infants. Prostaglandin synthetase inhibitors such as indomethacin promote PDA closure but also have ...potential side effects. The effect of the prophylactic use of indomethacin, where infants who may not have gone on to develop a symptomatic PDA would be exposed to indomethacin, warrants particular scrutiny.
To determine the effect of prophylactic indomethacin on mortality and morbidity in preterm infants.
The standard search strategy of the Cochrane Neonatal Review Group was used. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 5, 2010), MEDLINE, EMBASE and CINAHL (until April 2010), conference proceedings, and previous reviews.
Randomised or quasi-randomised controlled trials that compared prophylactic indomethacin versus placebo or no drug in preterm infants.
The standard methods of the Cochrane Neonatal Review Group were used, with separate evaluation of trial quality and data extraction by two review authors.
Nineteen eligible trials in which 2872 infants participated were identified. Most participants were very low birth weight, but the largest single trial restricted participation to extremely low birth weight infants (N = 1202). The trials were generally of good quality.The incidence of symptomatic PDA typical relative risk (RR) 0.44, 95% confidence interval (CI) 0.38 to 0.50 and PDA surgical ligation (typical RR 0.51, 95% CI 0.37,0.71) was significantly lower in treated infants. Prophylactic indomethacin also significantly reduced the incidence of severe intraventricular haemorrhage (typical RR 0.66, 95% CI 0.53 to 0.82). Meta-analyses found no evidence of an effect on mortality (typical RR 0.96, 95% CI 0.81 to 1.12) or on a composite of death or severe neurodevelopmental disability assessed at 18 to 36 months old (typical RR 1.02, 95% CI 0.90, 1.15).
Prophylactic indomethacin has short-term benefits for preterm infants including a reduction in the incidence of symptomatic PDA, PDA surgical ligation, and severe intraventricular haemorrhage. However, there is no evidence of effect on mortality or neurodevelopment.
Infants at higher risk of bronchopulmonary dysplasia had increased rates of survival free of cerebral palsy after postnatal corticosteroid treatment in a previous metaregression of data from 14 ...randomized controlled trials. The relationship persists and is stronger in an updated analysis with data from 20 randomized controlled trials.
Cohort studies have suggested that nasal continuous positive airway pressure (CPAP) starting in the immediate postnatal period before the onset of respiratory disease (prophylactic CPAP) may be ...beneficial in reducing the need for intubation and intermittent positive pressure ventilation (IPPV), and in preventing bronchopulmonary dysplasia (BPD), in preterm or low birth weight infants.
To determine if prophylactic nasal CPAP (started within the first 15 minutes) or very early nasal CPAP regardless of respiratory status (started within the first hour of life), reduces the use of mechanical ventilation and the incidence of bronchopulmonary dysplasia without any adverse effects in preterm infants.
A comprehensive search was run on 6 November 2020 in the Cochrane Central Register of Controlled Trials (CENTRAL via CRS Web) and MEDLINE via Ovid. We also searched the reference lists of retrieved studies.
We included all randomised controlled trials (RCTs) and quasi-RCTs in preterm infants (under 37 weeks of gestation). We included trials if they compared prophylactic nasal CPAP (started within the first 15 minutes) or very early nasal CPAP (started within the first hour of life) in infants with minimal signs of respiratory distress with 'supportive care', such as supplemental oxygen therapy, standard nasal cannula, or mechanical ventilation. We excluded studies where prophylactic CPAP was compared with CPAP along with co-interventions.
We used the standard methods of Cochrane Neonatal, including independent study selection, assessment of trial quality, and extraction of data by two review authors.
We included eight trials (seven from the previous version of the review and one new study), recruiting 3201 babies, in the meta-analysis. Four trials, involving 765 babies, compared CPAP with supportive care, and three trials (2364 babies) compared CPAP with mechanical ventilation. One trial (72 babies) compared prophylactic CPAP with very early CPAP. Apart from a lack of blinding of the intervention, we judged seven studies to have a low risk of bias. However, one study had a high risk of selection bias. Prophylactic or very early CPAP compared to supportive care There may be a reduction in failed treatment (risk ratio (RR) 0.6, 95% confidence interval (CI) 0.49 to 0.74; risk difference (RD) -0.16, 95% CI -0.34 to 0.02; 4 studies, 765 infants; very low certainty evidence). CPAP possibly reduces BPD at 36 weeks (RR 0.76, 95% CI 0.51 to 1.14; 3 studies, 683 infants, moderate certainty evidence); there may be little or no difference in death (RR 1.04, 95% CI 0.56 to 1.93; 4 studies, 765 infants; moderate certainty evidence). Prophylactic CPAP may reduce the composite outcome of death or BPD (RR 0.69, 95% CI 0.40 to 1.19; 1 study, 256 infants; low certainty evidence). There may be no difference in pulmonary air leak (pneumothorax) (RR 0.75, 95% CI 0.35 to 1.16; 3 studies, 568 infants; low certainty evidence), or intraventricular haemorrhage (IVH) Grade 3 or 4 (RR 0.96, 95% CI 0.39 to 2.37; 2 studies, 486 infants; moderate certainty evidence). Neurodevelopmental impairment was not reported in any of the studies. Prophylactic or very early CPAP compared to mechanical ventilation There was probably a reduction in the incidence of BPD at 36 weeks (RR 0.89, 95% CI 0.8 to 0.99; RD -0.04, 95% CI -0.08 to 0.00; 3 studies, 2150 infants; moderate certainty evidence); and death or BPD (RR 0.89, 95% CI 0.81 to 0.97; RD -0.05, 95% CI -0.09 to 0.01; 3 studies, 2358 infants; moderate certainty evidence). There was also probably a reduction in the need for mechanical ventilation (failed treatment) (RR 0.49, 95% CI 0.45 to 0.54; RD -0.50, 95% CI -0.54 to -0.45; 2 studies, 1042 infants; moderate certainty evidence). There was probably a reduction in the incidence of death (RR 0.82, 95% CI 0.66 to 1.03; 3 studies, 2358 infants; moderate certainty evidence); pulmonary air leak (pneumothorax) (RR 1.24, 95% CI 0.91 to 1.69; 3 studies, 2357 infants; low certainty evidence); and IVH Grade 3 or 4 (RR 1.09, 95% CI 0.86 to 1.39; 3 studies, 2301 infants; moderate certainty evidence). One study in this comparison reported that there was probably little or no difference between the groups in the incidence of neurodevelopmental impairment at 18 to 22 months (RR 0.91, 95% CI 0.62 to 1.32; 976 infants; moderate certainty evidence). Prophylactic CPAP compared with very early CPAP There was one study in this comparison. We are very uncertain whether there is any difference in the incidence of BPD (RR 0.5, 95% CI 0.05 to 5.27; very low certainty evidence). The combined outcome of death and BPD was not reported, and failed treatment was reported but without data. There may have been little to no effect on death (RR 0.75, 95% CI 0.29 to1.94; 1 study, 72 infants; very low certainty evidence). Intraventricular haemorrhage Grade 3 or 4 and neurodevelopmental outcomes were not reported in this study. Pulmonary air leak (pneumothorax) was reported in this study, but there were no events in either group.
For preterm and very preterm infants, there is insufficient evidence to evaluate prophylactic CPAP compared to oxygen therapy and other supportive care. When compared to mechanical ventilation, prophylactic nasal CPAP in very preterm infants reduces the incidence of BPD, the combined outcome of death and BPD, and mechanical ventilation. There is probably no difference in neurodevelopmental impairment at 18 to 22 months of age. When prophylactic CPAP is compared to early CPAP, we are very uncertain about whether there is any difference between prophylactic and very early CPAP. There is no information about the effect of prophylactic or very early CPAP in late preterm infants. There is one study awaiting classification.
Caffeine as tested in the CAP trial is safe and effective for preterm infants with birthweights less than 1250 g. Evidence for its use beyond the indications and timing used in this trial is of low ...quality and conflicting. Some studies suggest that earlier use of caffeine increases the risk of mortality while others suggest it has important benefits. It appears that infants with apnea of prematurity and those receiving assisted ventilation are the most likely to benefit from caffeine. Based on currently available evidence, routine early prescription of caffeine does not appear to be indicated. Infants continue to have potentially damaging episodes of hypoxia secondary to apnea beyond 34 weeks’ postmenstrual age. It is unclear whether prolonged use of caffeine improves outcomes in these infants. Randomized trials to resolve these uncertainties are required. They need to be large, at least the size of the CAP trial, and include neurodevelopmental outcomes.
Non-invasive respiratory support is increasingly used for the management of respiratory dysfunction in preterm infants. This approach runs the risk of under-treating those with respiratory distress ...syndrome (RDS), for whom surfactant administration is of paramount importance. Several techniques of minimally invasive surfactant therapy have been described. This review focuses on surfactant administration to spontaneously breathing infants via a thin catheter briefly inserted into the trachea.
Primary objectives In non-intubated preterm infants with established RDS or at risk of developing RDS to compare surfactant administration via thin catheter with: 1. intubation and surfactant administration through an endotracheal tube (ETT); or 2. continuation of non-invasive respiratory support without surfactant administration or intubation. Secondary objective 1. To compare different methods of surfactant administration via thin catheter Planned subgroup analyses included gestational age, timing of intervention, and use of sedating pre-medication during the intervention.
We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL), in the Cochrane Library; Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Daily and Versions(R); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL), on 30 September 2020. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-randomised trials.
We included randomised trials comparing surfactant administration via thin catheter (S-TC) with (1) surfactant administration through an ETT (S-ETT), or (2) continuation of non-invasive respiratory support without surfactant administration or intubation. We also included trials comparing different methods/strategies of surfactant administration via thin catheter. We included preterm infants (at < 37 weeks' gestation) with or at risk of RDS.
Review authors independently assessed study quality and risk of bias and extracted data. Authors of all studies were contacted regarding study design and/or missing or unpublished data. We used the GRADE approach to assess the certainty of evidence.
We included 16 studies (18 publications; 2164 neonates) in this review. These studies compared surfactant administration via thin catheter with surfactant administration through an ETT with early extubation (Intubate, Surfactant, Extubate technique - InSurE) (12 studies) or with delayed extubation (2 studies), or with continuation of continuous positive airway pressure (CPAP) and rescue surfactant administration at pre-specified criteria (1 study), or compared different strategies of surfactant administration via thin catheter (1 study). Two trials reported neurosensory outcomes of of surviving participants at two years of age. Eight studies were of moderate certainty with low risk of bias, and eight studies were of lower certainty with unclear risk of bias. S-TC versus S-ETT in preterm infants with or at risk of RDS Meta-analyses of 14 studies in which S-TC was compared with S-ETT as a control demonstrated a significant decrease in risk of the composite outcome of death or bronchopulmonary dysplasia (BPD) at 36 weeks' postmenstrual age (risk ratio (RR) 0.59, 95% confidence interval (CI) 0.48 to 0.73; risk difference (RD) -0.11, 95% CI -0.15 to -0.07; number needed to treat for an additional beneficial outcome (NNTB) 9, 95% CI 7 to 16; 10 studies; 1324 infants; moderate-certainty evidence); the need for intubation within 72 hours (RR 0.63, 95% CI 0.54 to 0.74; RD -0.14, 95% CI -0.18 to -0.09; NNTB 8, 95% CI; 6 to 12; 12 studies, 1422 infants; moderate-certainty evidence); severe intraventricular haemorrhage (RR 0.63, 95% CI 0.42 to 0.96; RD -0.04, 95% CI -0.08 to -0.00; NNTB 22, 95% CI 12 to 193; 5 studies, 857 infants; low-certainty evidence); death during first hospitalisation (RR 0.63, 95% CI 0.47 to 0.84; RD -0.02, 95% CI -0.10 to 0.06; NNTB 20, 95% CI 12 to 58; 11 studies, 1424 infants; low-certainty evidence); and BPD among survivors (RR 0.57, 95% CI 0.45 to 0.74; RD -0.08, 95% CI -0.11 to -0.04; NNTB 13, 95% CI 9 to 24; 11 studies, 1567 infants; moderate-certainty evidence). There was no significant difference in risk of air leak requiring drainage (RR 0.58, 95% CI 0.33 to 1.02; RD -0.03, 95% CI -0.05 to 0.00; 6 studies, 1036 infants; low-certainty evidence). None of the studies reported on the outcome of death or survival with neurosensory disability. Only one trial compared surfactant delivery via thin catheter with continuation of CPAP, and one trial compared different strategies of surfactant delivery via thin catheter, precluding meta-analysis.
Administration of surfactant via thin catheter compared with administration via an ETT is associated with reduced risk of death or BPD, less intubation in the first 72 hours, and reduced incidence of major complications and in-hospital mortality. This procedure had a similar rate of adverse effects as surfactant administration through an ETT. Data suggest that treatment with surfactant via thin catheter may be preferable to surfactant therapy by ETT. Further well-designed studies of adequate size and power, as well as ongoing studies, will help confirm and refine these findings, clarify whether surfactant therapy via thin tracheal catheter provides benefits over continuation of non-invasive respiratory support without surfactant, address uncertainties within important subgroups, and clarify the role of sedation.
As measurement of arterial oxygen saturation (SpO2) is common in the delivery room, target SpO2 ranges allow clinicians to titrate oxygen therapy for preterm infants in order to achieve saturation ...levels similar to those seen in normal term infants in the first minutes of life. However, the influence of the onset of ventilation and the timing of cord clamping on systemic and cerebral oxygenation is not known.
We investigated whether the initiation of ventilation, prior to, or after umbilical cord clamping, altered systemic and cerebral oxygenation in preterm lambs.
Systemic and cerebral blood-flows, pressures and peripheral SpO2 and regional cerebral tissue oxygenation (SctO2) were measured continuously in apnoeic preterm lambs (126±1 day gestation). Positive pressure ventilation was initiated either 1) prior to umbilical cord clamping, or 2) after umbilical cord clamping. Lambs were monitored intensively prior to intervention, and for 10 minutes following umbilical cord clamping.
Clamping the umbilical cord prior to ventilation resulted in a rapid decrease in SpO2 and SctO2, and an increase in arterial pressure, cerebral blood flow and cerebral oxygen extraction. Ventilation restored oxygenation and haemodynamics by 5-6 minutes. No such disturbances in peripheral or cerebral oxygenation and haemodynamics were observed when ventilation was initiated prior to cord clamping.
The establishment of ventilation prior to umbilical cord clamping facilitated a smooth transition to systemic and cerebral oxygenation following birth. SpO2 nomograms may need to be re-evaluated to reflect physiological management of preterm infants in the delivery room.
There are potential benefits and harms of hyperoxemia and hypoxemia for extremely preterm infants receiving more vs less supplemental oxygen.
To compare the effects of different target ranges for ...oxygen saturation as measured by pulse oximetry (Spo2) on death or major morbidity.
Prospectively planned meta-analysis of individual participant data from 5 randomized clinical trials (conducted from 2005-2014) enrolling infants born before 28 weeks' gestation.
Spo2 target range that was lower (85%-89%) vs higher (91%-95%).
The primary outcome was a composite of death or major disability (bilateral blindness, deafness, cerebral palsy diagnosed as ≥2 level on the Gross Motor Function Classification System, or Bayley-III cognitive or language score <85) at a corrected age of 18 to 24 months. There were 16 secondary outcomes including the components of the primary outcome and other major morbidities.
A total of 4965 infants were randomized (2480 to the lower Spo2 target range and 2485 to the higher Spo2 range) and had a median gestational age of 26 weeks (interquartile range, 25-27 weeks) and a mean birth weight of 832 g (SD, 190 g). The primary outcome occurred in 1191 of 2228 infants (53.5%) in the lower Spo2 target group and 1150 of 2229 infants (51.6%) in the higher Spo2 target group (risk difference, 1.7% 95% CI, -1.3% to 4.6%; relative risk RR, 1.04 95% CI, 0.98 to 1.09, P = .21). Of the 16 secondary outcomes, 11 were null, 2 significantly favored the lower Spo2 target group, and 3 significantly favored the higher Spo2 target group. Death occurred in 484 of 2433 infants (19.9%) in the lower Spo2 target group and 418 of 2440 infants (17.1%) in the higher Spo2 target group (risk difference, 2.8% 95% CI, 0.6% to 5.0%; RR, 1.17 95% CI, 1.04 to 1.31, P = .01). Treatment for retinopathy of prematurity was administered to 220 of 2020 infants (10.9%) in the lower Spo2 target group and 308 of 2065 infants (14.9%) in the higher Spo2 target group (risk difference, -4.0% 95% CI, -6.1% to -2.0%; RR, 0.74 95% CI, 0.63 to 0.86, P < .001). Severe necrotizing enterocolitis occurred in 227 of 2464 infants (9.2%) in the lower Spo2 target group and 170 of 2465 infants (6.9%) in the higher Spo2 target group (risk difference, 2.3% 95% CI, 0.8% to 3.8%; RR, 1.33 95% CI, 1.10 to 1.61, P = .003).
In this prospectively planned meta-analysis of individual participant data from extremely preterm infants, there was no significant difference between a lower Spo2 target range compared with a higher Spo2 target range on the primary composite outcome of death or major disability at a corrected age of 18 to 24 months. The lower Spo2 target range was associated with a higher risk of death and necrotizing enterocolitis, but a lower risk of retinopathy of prematurity treatment.
Outcomes for extremely premature infants Glass, Hannah C; Costarino, Andrew T; Stayer, Stephen A ...
Anesthesia and analgesia,
2015-June, Letnik:
120, Številka:
6
Journal Article
Recenzirano
Odprti dostop
Premature birth is a significant cause of infant and child morbidity and mortality. In the United States, the premature birth rate, which had steadily increased during the 1990s and early 2000s, has ...decreased annually for 7 years and is now approximately 11.39%. Human viability, defined as gestational age at which the chance of survival is 50%, is currently approximately 23 to 24 weeks in developed countries. Infant girls, on average, have better outcomes than infant boys. A relatively uncomplicated course in the intensive care nursery for an extremely premature infant results in a discharge date close to the prenatal estimated date of confinement. Despite technological advances and efforts of child health experts during the last generation, the extremely premature infant (less than 28 weeks gestation) and extremely low birth weight infant (<1000 g) remain at high risk for death and disability with 30% to 50% mortality and, in survivors, at least 20% to 50% risk of morbidity. The introduction of continuous positive airway pressure, mechanical ventilation, and exogenous surfactant increased survival and spurred the development of neonatal intensive care in the 1970s through the early 1990s. Routine administration of antenatal steroids during premature labor improved neonatal mortality and morbidity in the late 1990s. The recognition that chronic postnatal administration of steroids to infants should be avoided may have improved outcomes in the early 2000s. Evidence from recent trials attempting to define the appropriate target for oxygen saturation in preterm infants suggests arterial oxygen saturation between 91% and 95% (compared with 85%-89%) avoids excess mortality; however, final analyses of data from these trials have not been published, so definitive recommendations are still pending. The development of neonatal neurocritical intensive care units may improve neurocognitive outcomes in this high-risk group. Long-term follow-up to detect and address developmental, learning, behavioral, and social problems is critical for children born at these early gestational ages.The striking similarities in response to extreme prematurity in the lung and brain imply that agents and techniques that benefit one organ are likely to also benefit the other. Finally, because therapy and supportive care continue to change, the outcomes of extremely low birth weight infants are ever evolving. Efforts to minimize injury, preserve growth, and identify interventions focused on antioxidant and anti-inflammatory pathways are now being evaluated. Thus, treating and preventing long-term deficits must be developed in the context of a "moving target."
Damage caused by lung overdistension (volutrauma) has been implicated in the development of bronchopulmonary dysplasia (BPD). Modern neonatal ventilation modes can target a set tidal volume as an ...alternative to traditional pressure-limited ventilation (PLV) using a fixed inflation pressure. Volume-targeted ventilation (VTV) aims to produce a more stable tidal volume in order to reduce lung damage and stabilise the partial pressure of carbon dioxide (pCO
).
To determine whether VTV compared with PLV leads to reduced rates of death and death or BPD in newborn infants and to determine whether use of VTV affected outcomes including air leak, cranial ultrasound findings and neurodevelopment.
We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 12), MEDLINE via PubMed (1966 to 13 January 2017), Embase (1980 to 13 January 2017) and CINAHL (1982 to 13 January 2017). We also searched clinical trials databases, conference proceedings and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. We contacted the principal investigators of studies to obtain supplementary information.
Randomised and quasi-randomised trials comparing VTV versus PLV in infants of less than 44 weeks' postmenstrual age and reporting clinically relevant outcomes.
We assessed risk of bias for each trial using Cochrane methodology. We evaluated quality of evidence for each outcome using GRADE criteria. We tabulated mortality, rates of BPD, short-term clinical outcomes and long-term developmental outcomes.
for categorical outcomes, we calculated typical estimates for risk ratios (RR), risk differences (RD) and number needed to treat for an additional beneficial outcome (NNTB). For continuous variables, we calculated typical estimates for mean differences (MD). We used 95% confidence intervals (CI) and assumed a fixed-effect model for meta-analysis.
Twenty randomised trials met our inclusion criteria; 16 parallel trials (977 infants) and four cross-over trials (88 infants). No studies were blinded and the quality of evidence for outcomes assessed varied from moderate to low.We found no difference in the primary outcome, death before hospital discharge, between VTV modes versus PLV modes (typical RR 0.75, 95% CI 0.53 to 1.07; low quality evidence). However, there was moderate quality evidence that the use of VTV modes resulted in a reduction in the primary outcome, death or BPD at 36 weeks' gestation (typical RR 0.73, 95% CI 0.59 to 0.89; typical NNTB 8, 95% CI 5 to 20) and the following secondary outcomes: rates of pneumothorax (typical RR 0.52, 95% CI 0.31 to 0.87; typical NNTB 20, 95% CI 11 to 100), mean days of mechanical ventilation (MD -1.35 days, 95% CI -1.83 to -0.86), rates of hypocarbia (typical RR 0.49, 95% CI 0.33 to 0.72; typical NNTB 3, 95% CI 2 to 5), rates of grade 3 or 4 intraventricular haemorrhage (typical RR 0.53, 95% CI 0.37 to 0.77; typical NNTB 11, 95% CI 7 to 25) and the combined outcome of periventricular leukomalacia with or without grade 3 or 4 intraventricular haemorrhage (typical RR 0.47, 95% CI 0.27 to 0.80; typical NNTB 11, 95% CI 7 to 33). VTV modes were not associated with any increased adverse outcomes.
Infants ventilated using VTV modes had reduced rates of death or BPD, pneumothoraces, hypocarbia, severe cranial ultrasound pathologies and duration of ventilation compared with infants ventilated using PLV modes. Further studies are needed to identify whether VTV modes improve neurodevelopmental outcomes and to compare and refine VTV strategies.
Newborn animal studies and pilot studies in humans suggest that mild hypothermia following peripartum hypoxia-ischaemia in newborn infants may reduce neurological sequelae without adverse effects.
To ...determine the effect of therapeutic hypothermia in encephalopathic asphyxiated newborn infants on mortality, long-term neurodevelopmental disability and clinically important side effects.
We used the standard search strategy of the Cochrane Neonatal Review Group as outlined in The Cochrane Library (Issue 2, 2007). Randomised controlled trials evaluating therapeutic hypothermia in term and late preterm 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, 2007, Issue 2), MEDLINE (1966 to June 2007), previous reviews including cross-references, abstracts, conferences, symposia proceedings, expert informants and journal handsearching. We updated this search in May 2012.
We included randomised controlled trials comparing the use of therapeutic hypothermia with standard care in encephalopathic term or late preterm infants with evidence of peripartum asphyxia and without recognisable major congenital anomalies. 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.
Four review authors independently selected, assessed the quality of and extracted data from the included studies. Study authors were contacted for further information. Meta-analyses were performed using risk ratios (RR) and risk differences (RD) for dichotomous data, and weighted mean difference for continuous data with 95% confidence intervals (CI).
We included 11 randomised controlled trials in this updated review, comprising 1505 term and late preterm infants with moderate/severe encephalopathy and evidence of intrapartum asphyxia. Therapeutic hypothermia resulted in a statistically significant and clinically important reduction in the combined outcome of mortality or major neurodevelopmental disability to 18 months of age (typical RR 0.75 (95% CI 0.68 to 0.83); typical RD -0.15, 95% CI -0.20 to -0.10); number needed to treat for an additional beneficial outcome (NNTB) 7 (95% CI 5 to 10) (8 studies, 1344 infants). Cooling also resulted in statistically significant reductions in mortality (typical RR 0.75 (95% CI 0.64 to 0.88), typical RD -0.09 (95% CI -0.13 to -0.04); NNTB 11 (95% CI 8 to 25) (11 studies, 1468 infants) and in neurodevelopmental disability in survivors (typical RR 0.77 (95% CI 0.63 to 0.94), typical RD -0.13 (95% CI -0.19 to -0.07); NNTB 8 (95% CI 5 to 14) (8 studies, 917 infants). Some adverse effects of hypothermia included an increase sinus bradycardia and a significant increase in thrombocytopenia.
There is evidence from the 11 randomised controlled trials included in this systematic review (N = 1505 infants) that therapeutic hypothermia is beneficial in term and late preterm newborns with hypoxic ischaemic encephalopathy. Cooling reduces mortality without increasing major disability in survivors. The benefits of cooling on survival and neurodevelopment outweigh the short-term adverse effects. Hypothermia should be instituted in term and late preterm infants with moderate-to-severe hypoxic ischaemic encephalopathy if identified before six hours of age. Further trials to determine the appropriate techniques of cooling, including refinement of patient selection, duration of cooling and method of providing therapeutic hypothermia, will refine our understanding of this intervention.