Trial of Selective Early Treatment of Patent Ductus Arteriosus with Ibuprofen

BACKGROUND

The cyclooxygenase inhibitor ibuprofen may be used to treat patent ductus arteriosus (PDA) in preterm infants. Whether selective early treatment of large PDAs with ibuprofen would improve short-term outcomes is not known.

METHODS

We conducted a multicenter, randomized, double-blind, placebo-controlled trial evaluating early treatment (≤72 hours after birth) with ibuprofen for a large PDA (diameter of ≥1.5 mm with pulsatile flow) in extremely preterm infants (born between 23 weeks 0 days' and 28 weeks 6 days' gestation). The primary outcome was a composite of death or moderate or severe bronchopulmonary dysplasia evaluated at 36 weeks of postmenstrual age.

RESULTS

A total of 326 infants were assigned to receive ibuprofen and 327 to receive placebo; 324 and 322, respectively, had data available for outcome analyses. A primary-outcome event occurred in 220 of 318 infants (69.2%) in the ibuprofen group and 202 of 318 infants (63.5%) in the placebo group (adjusted risk ratio, 1.09; 95% confidence interval [CI], 0.98 to 1.20; P = 0.10). A total of 44 of 323 infants (13.6%) in the ibuprofen group and 33 of 321 infants (10.3%) in the placebo group died (adjusted risk ratio, 1.32; 95% CI, 0.92 to 1.90). Among the infants who survived to 36 weeks of postmenstrual age, moderate or severe bronchopulmonary dysplasia occurred in 176 of 274 (64.2%) in the ibuprofen group and 169 of 285 (59.3%) in the placebo group (adjusted risk ratio, 1.09; 95% CI, 0.96 to 1.23). Two unforeseeable serious adverse events occurred that were possibly related to ibuprofen.

CONCLUSIONS

The risk of death or moderate or severe bronchopulmonary dysplasia at 36 weeks of postmenstrual age was not significantly lower among infants who received early treatment with ibuprofen than among those who received placebo. (Funded by the National Institute for Health Research Health Technology Assessment Programme; Baby-OSCAR ISRCTN Registry number, ISRCTN84264977.).

Association between immediate oxygenation response and survival in preterm infants receiving rescue inhaled nitric oxide therapy for hypoxemia from pulmonary hypertension: A systematic review and meta-analysis

PURPOSE

To investigate whether immediate response to inhaled nitric oxide (iNO) therapy is associated with reduced mortality in preterm infants with hypoxemic respiratory failure (HRF) and pulmonary hypertension (PH).

METHODS

A systematic review and meta-analysis of observational studies was conducted to examine the association between immediate response (improved oxygenation ≤6 h) compared to non-response, and all-cause mortality among preterm infants <34 weeks gestational age without congenital anomalies or genetic disorders who received iNO treatment. Adjusted and unadjusted odds ratio, were pooled using a random effects meta-analysis Hartung-Knapp-Sidik-Jonkman approach. Subgroup analyses were planned for infants with preterm premature rupture of membranes (PPROM) and those treated within 72 h after birth.

RESULTS

The primary analysis included 5 eligible studies, a total of 400 infants (196 responders; 204 non-responders). The studies were rated as low to moderate risk of bias based on the Quality in Prognostic Studies tool. Immediate iNO responsiveness was associated with reduced odds of mortality [odds ratio (OR) 0.22, 95 % confidence interval (95 % CI) (0.10-0.49)]. Although there was insufficient data for a subgroup analysis of infants with PPROM, infants treated with iNO within 72 h demonstrated consistent findings of reduced mortality [OR 0.21 95 % CI (0.13-0.36)]. Based on the GRADE approach, considering the risk of bias of included studies, the overall strength of evidence was rated as moderate.

CONCLUSION

There is evidence to suggest that immediate improvement in oxygenation following iNO therapy is associated with reduced odds of mortality before discharge in preterm infants with HRF and clinically suspected or confirmed PH.

Targeted neonatal echocardiography training: a survey of trainees in a region of England

Targeted neonatal echocardiography (TNE) is an important skill to advise diagnosis and management. Training in TNE is currently optional for neonatal subspecialty (grid) trainees and accessing training is often challenging. We disseminated a survey, asking neonatal grid trainees for their views on TNE training. 48 out of 91 trainees (53%) completed the survey. 96% of trainees (n=48) wanted to learn TNE with similar numbers eager to access a formal training package, using a variety of teaching media. Identified barriers to TNE training included time, access to supervision and the perceived complexity of the skill. These findings will influence the design and delivery of a regional TNE training programme.

Increase in the use of inhaled nitric oxide in neonatal intensive care units in England: a retrospective population study

OBJECTIVE

To describe temporal changes in inhaled nitric oxide (iNO) use in English neonatal units between 2010 and 2015.

DESIGN

Retrospective analysis using data extracted from the National Neonatal Research Database.

SETTING

All National Health Service neonatal units in England.

PATIENTS

Infants of all gestational ages born 2010-2015 admitted to a neonatal unit and received intensive care.

MAIN OUTCOME MEASURES

Proportion of infants who received iNO; age at initiation and duration of iNO use.

RESULTS

4.9% (6346/129 883) of infants received iNO; 31% (1959/6346) were born <29 weeks, 18% (1152/6346) 29-33 weeks and 51% (3235/6346)>34 weeks of gestation. Between epoch 1 (2010-2011) and epoch 3 (2014-2015), there was (1) an increase in the proportion of infants receiving iNO: <29 weeks (4.9% vs 15.9%); 29-33 weeks (1.1% vs 4.8%); >34 weeks (4.5% vs 5.0%), (2) increase in postnatal age at iNO initiation: <29 weeks 10 days vs 18 days; 29-33 weeks 2 days vs 10 days, (iii) reduction in iNO duration: <29 weeks (3 days vs 2 days); 29-33 weeks (2 days vs 1 day).

CONCLUSIONS

Between 2010 and 2015, there was an increase in the use of iNO among infants admitted to English neonatal units. This was most notable among the most premature infants with an almost fourfold increase. Given the cost of iNO therapy, limited evidence of efficacy in preterm infants and potential for harm, we suggest that exposure to iNO should be limited, ideally to infants included in research studies (either observational or randomised placebo-controlled trial) or within a protocolised pathway. Development of consensus guidelines may also help standardise practice.

Variation in the definition of pulmonary hypertension and clinical indications for the use of nitric oxide in neonatal clinical trials

AIM

Pulmonary hypertension (PH) frequently complicates neonatal hypoxaemic respiratory failure, but is inconsistently defined. We aimed to describe the variation among randomised controlled trials (RCTs) of inhaled nitric oxide (iNO), in relation to the definition of PH and/or hypoxaemic respiratory failure used to select patients for trial inclusion.

METHODS

PubMed, Cochrane Library and ClinicalTrials.gov were systematically searched for RCTs of iNO in neonates. Included studies were assessed for clinical and/or echocardiography criteria used to define PH/hypoxaemic respiratory failure.

RESULTS

Thirty-two trials were included in this review, of which 23 enrolled infants ≥34 weeks' gestation. Echocardiographic diagnosis was used in 21 studies, but there was considerable variation in the echocardiographic parameters used to diagnose PH. The most commonly used indices included markers of tricuspid regurgitation and extrapulmonary shunt.

CONCLUSION

There is wide variation in the definition of PH used to select infants for inclusion into RCTs of iNO therapy in neonates. We recommend that an international consensus be reached on which parameters should be used and the thresholds defining severity of disease.

Cost of nitric oxide therapy in neonates

A retrospective observational cohort study was performed to review the cost of inhaled nitric oxide (iNO) therapy in a UK neonatal intensive care setting over a 4-year period. 188 neonates with a median (IQR) gestational age and birth weight of 27 (24-37) weeks and 980 (695-2812) g, respectively, were treated with iNO. The median (IQR) duration of iNO therapy was 60 (22-129) hours. The mean cost of iNO therapy was approximately £820 per baby treated equivalent to £8.50 per hour of therapy. Alternative pricing models suggested a calculated cost of iNO therapy of between approximately £950 and £1350 per baby.

Prostaglandin E 2 in a preterm infant with coarctation of the aorta

Prostaglandins are widely used in aortic coarctation to maintain ductal patency and preserve systemic perfusion until surgical intervention can be performed. Although the short-term use of prostaglandins to ameliorate aortic narrowing in neonates with a closed ductus has been reported, it has not been described as a longer term therapy in extremely preterm neonates. A 27-week gestation baby weighing 560 g presented at 40 days of age with coarctation and a closed ductus arteriosus. He was successfully treated with a 7-week course of prostaglandin E₂ therapy because surgical intervention was not deemed feasible in view of his size. Treatment resulted in a relaxation of the aortic constriction and improvement in aortic blood flow velocity profile, highlighting the value of long-term prostaglandin therapy in this population and supporting the hypothesis that the presence of ductal tissue contributes to the development of juxtaductal aortic constriction in some extremely preterm infants.

Nitric Oxide in Pulmonary Hypoplasia: Results from the European iNO Registry

OBJECTIVES

The aim of this work was to describe treatment response and outcome data for preterm infants with pulmonary hypoplasia treated with inhaled nitric oxide (iNO). We hypothesised that an acute oxygenation response to iNO would be associated with survival.

DESIGN

A retrospective observational study design was used to identify cases of pulmonary hypoplasia in preterm infants <34 weeks' gestation reported to the European iNO Registry. Demographic and clinical data were collected including oxygenation and echocardiographic parameters. The primary outcome was acute oxygenation response defined as a reduction in fractional inspired oxygen of >0.15. Outcome data included chronic lung disease (CLD) and death.

RESULTS

Seventy-two infants with pulmonary hypoplasia were treated with iNO during a 10-year period (2007-2016). In total, 30/69 (43%) of the infants showed a significant improvement in oxygenation and were categorised as "responders." Thirty-one treated infants died, and 19 survivors developed CLD. Although there were no differences in demographics and baseline cardiorespiratory parameters between responders and non-responders, an acute response was significantly associated with survival. Neither pulmonary hypertension nor PPHN (persistent pulmonary hypertension of the newborn) physiology predicted the acute response to iNO or survival.

CONCLUSION

Although the acute oxygenation response to iNO therapy in pulmonary hypoplasia is comparable to other respiratory disorders in preterm infants, mortality in this group remains very high. An acute response is associated with survival and suggests that a short therapeutic trial of iNO therapy is warranted in this population. This study underscores the value of registries in evaluating therapies for rare neonatal disorders, although their limitations must be recognised.

Corticosteroids for treating hypotension in preterm infants

BACKGROUND

Systemic hypotension is a relatively common complication of preterm birth and is associated with periventricular haemorrhage, periventricular white matter injury and adverse neurodevelopmental outcome. Corticosteroid treatment has been used as an alternative or an adjunct to conventional treatment with volume expansion and vasopressor/inotropic therapy.

OBJECTIVES

To determine the effectiveness and safety of corticosteroids used either as primary treatment of hypotension or for the treatment of refractory hypotension in preterm infants.

SEARCH METHODS

Randomized or quasi-randomised controlled trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 2, 2011), MEDLINE (1996 to Jan 2011), EMBASE (1974 to Jan 2011), CINAHL (1981 to 2011), reference lists of published papers and abstracts from the Pediatric Academic Societies and the European Society for Pediatric Research meetings published in Pediatric Research (1995 to 2011).

SELECTION CRITERIA

We included all randomised or quasi-randomised controlled trials investigating the effect of corticosteroid therapy in the treatment of hypotension in preterm infants (< 37 weeks gestation) less than 28 days old. Studies using corticosteroids as primary treatment were included as well as studies using corticosteroids in babies with hypotension resistant to inotropes/pressors and volume therapy. We included studies comparing oral/intravenous corticosteroids with placebo, other drugs used for providing cardiovascular support or no therapy in this review.

DATA COLLECTION AND ANALYSIS

Methodological quality of eligible studies was assessed according to the methods used for minimising selection bias, performance bias, attrition bias and detection bias. Studies that evaluated corticosteroids (1) as primary treatment for hypotension or (2) for refractory hypotension unresponsive to prior use of inotropes/pressors and volume therapy, were analysed using separate comparisons. Data were analysed using the standard methods of the Neonatal Review Group using Rev Man 5.1.2. Treatment effect was analysed using relative risk, risk reduction, number needed to treat for categorical outcomes and weighted mean difference for outcomes measured on a continuous scale, with 95% confidence intervals.

MAIN RESULTS

Four studies were included in this review enrolling a total of 123 babies. In one study, persistent hypotension was more common in hydrocortisone treated infants as compared to those who received dopamine as primary treatment for hypotension (RR 8.2, 95% CI 0.47 to 142.6; RD 0.19, 95% CI 0.01 to 0.37). In two studies comparing steroid versus placebo, persistent hypotension (defined as a continuing need for inotrope infusion) was less common in steroid treated infants as compared to controls who received placebo for refractory hypotension (RR 0.35, 95% CI 0.19 to 0.65; RD -0.47, 95% CI - 0.68 to - 0.26; NNT = 2.1, 95% CI 1.47, 3.8). There were no statistically significant effects on any other short or long-term outcome. A further two studies that have only been published in abstract form to date, may be eligible for inclusion in a future update of this review.

AUTHORS' CONCLUSIONS

Hydrocortisone may be as effective as dopamine when used as a primary treatment for hypotension. But the long term safety data on the use of hydrocortisone in this manner is unknown.Steroids are effective in treatment of refractory hypotension in preterm infants without an increase in short term adverse consequences. However, long term safety or benefit data is lacking. With long term benefit or safety data lacking steroids cannot be recommended routinely for the treatment of hypotension in preterm infants.

Critical incident reporting in neonatal practice

Patient safety incidents (PSIs) occur relatively frequently in healthcare. Incident-reporting systems are designed to systematically collect information relating to PSIs in order to identify and rectify problems in the delivery of clinical care. This review provides an overview of the incident reporting process and summarises local and national data of PSIs reported in a neonatal population.

Telomere length dynamics differ in foetal and early post-natal human leukocytes in a longitudinal study

Haemopoietic stem cells (HSC) undergo a process of self renewal to constantly maintain blood cell turnover. However, it has become apparent that adult HSC lose their self-renewal ability with age. Telomere shortening in peripheral blood leukocytes has been seen to occur with age and it has been associated with loss of HSC proliferative capacity and cellular ageing. In contrast foetal HSC are known to have greater proliferative capacity than post-natal stem cells. However it is unknown whether they undergo a similar process of telomere shortening. In this study we show a more accentuated rate of telomere loss in leukocytes from pre term infants compared to human foetuses of comparable age followed longitudinally for 8-12 weeks in a longitudinal study. Our results point to a difference in HSC behaviour between foetal and early postnatal life which is independent of age but may be influenced by events at birth itself.

Corticosteroids for treating hypotension in preterm infants

BACKGROUND

Systemic hypotension is a relatively common complication of preterm birth and is associated with periventricular haemmorhage, periventricular white matter injury and adverse neurodevelopmental outcome. Corticosteroid treatment has been used as an alternative, or an adjunct, to conventional treatment with volume expansion and vasopressor/inotropic therapy.

OBJECTIVES

To determine the effectiveness and safety of corticosteroids used either as primary treatment of hypotension or for the treatment of refractory hypotension in preterm infants.

SEARCH STRATEGY

Randomized or quasi-randomized controlled trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2005), MEDLINE (1996 - June 2005), EMBASE (1974 - June 2005), reference lists of published papers and abstracts from the Pediatric Academic Societies and the European Society for Pediatric Research meetings published in Pediatric Research (1995 - 2004).

SELECTION CRITERIA

We included all randomised or quasi-randomised controlled trials investigating the effect of corticosteroid therapy in the treatment of hypotension in preterm infants (< 37 weeks gestation) less than 28 days old. Studies using corticosteroids as primary treatment were included as well as studies using corticosteroids in babies with hypotension resistant to inotropes/pressors and volume therapy. We included studies comparing oral/intravenous corticosteroids with placebo, other drugs used for providing cardiovascular support or no therapy in this review.

DATA COLLECTION AND ANALYSIS

Methodological quality of eligible studies was assessed according to the methods used for minimising selection bias, performance bias, attrition bias and detection bias. Studies that evaluated corticosteroids (1) as primary treatment for hypotension or (2) for refractory hypotension unresponsive to prior use of inotropes/pressors and volume therapy, were analysed using separate comparisons. Data were analysed using the standard methods of the Neonatal Review Group using Rev Man 4.2.7. Treatment effect was analysed using relative risk, risk reduction, number needed to treat for categorical outcomes and weighted mean difference for outcomes measured on a continuous scale, with 95% confidence intervals.

MAIN RESULTS

Two studies were included in this review enrolling a total of 57 babies. In the first study, persistent hypotension was more common in hydrocortisone treated infants as compared to those who received dopamine as primary treatment for hypotension (RR 8.2, 95% CI 0.47 to 142.6; RD 0.19, 95% CI 0.01 to 0.37). In the second study, persistent hypotension (defined as a continuing need for epinephrine infusion) was less common in dexamethasone treated infants as compared to controls who received placebo for refractory hypotension (RR 0.42 , 95% CI 0.17 to 1.06; RD -0.51, 95% CI - 0.91 to - 0.12). There were no statistically significant effects on any other short or long-term outcome. It was not considered appropriate to perform a meta-analysis. A further two studies that have only been published in abstract form to date, may be eligible for inclusion in a future update of this review.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support the routine use of steroids in the treatment of primary or refractory neonatal hypotension. Hydrocortisone may be as effective as dopamine in treating primary hypotension, but there are no data regarding the long-term safety of steroids used for this indication.A single dose of dexamethasone may be effective in treating preterm infants with refractory hypotension receiving epinephrine. However, given the lack of data on long-term safety dexamethasone cannot be recommended for routine use in preterm hypotension.

Sequential cardiac troponin T following delivery and its relationship with myocardial performance in neonates with respiratory distress syndrome

We measured serial cardiac troponin T in babies with respiratory distress syndrome and in "healthy" controls (no cardiorespiratory support required). We investigated relationships between cardiac troponin T and myocardial performance in respiratory distress syndrome. This was a prospective observational study at a large tertiary maternity unit that recruited 104 "healthy" babies from whom individual samples were collected. A further 24 infants with respiratory distress syndrome and 14 "healthy" preterm infants had serial sampling over the first three days. We measured fractional shortening in 14 of the infants with respiratory distress syndrome. Cardiac troponin T rose from a median (interquartile range) of 10 (10-11) pg/mL on day one to 34 (22-46) pg/mL by day three, p=0.005, in "healthy" babies. In respiratory distress syndrome levels were higher, 91 (46-135) pg/mL at 6 (5-7) hours of age, p<0.001, and remained so for all three days. In babies with respiratory distress syndrome on day one cardiac troponin T correlated negatively with fractional shortening, Rho=-0.831, p<0.001, but this correlation did not persist. In "healthy" babies there is a minimal rise of cardiac troponin T by day 3. In respiratory distress syndrome there is an early and sustained elevation of cardiac troponin T, with a negative relationship with fraction shortening, suggesting significant myocardial damage of antenatal/intrapartum origin, giving rise to measurable dysfunction.

Nasal potential difference increases with gestation in moderately preterm neonates on the first postnatal day

At birth the mammalian airway switches from liquid secretion to absorption, an important mechanism in lung liquid clearance. Airway ion transport was examined on the first postnatal day in 38 moderately preterm infants (29-36 weeks gestation). The absorptive airway ion transport capacity was well developed regardless of respiratory condition and there was little capacity for Cl- secretion.

Treated threshold stage 3 versus spontaneously regressed subthreshold stage 3 retinopathy of prematurity: a study of motility, refractive, and anatomical outcomes at 6 months and 36 months

AIM

To compare the visual acuity (VA), spherical equivalent refractive error, motility, and anatomical outcomes in children with treated regressed threshold stage 3 retinopathy of prematurity (ROP) and those with spontaneously regressed subthreshold stage 3 ROP.

METHOD

6 month and 3 year data collected from infants examined between 1989 and 1999 with regressed stage 3 ROP, with or without treatment were retrospectively reviewed.

RESULTS

85 infants were included in this study. 40 eyes received cryotherapy, 81 eyes laser photocoagulation, and 34 eyes had spontaneously regressed subthreshold stage 3 ROP. Grating acuity score > or =2 cycles/degree (c/d) at 6 months was predictive of optotype acuity > or =6/9 in 69% of eyes and a score <2 c/d at 6 months was predictive of acuity < 6/9 in 88% of eyes. Eyes with subthreshold stage 3 ROP were twice as likely to have VA of 6/9 or better at 36 months than the treated eyes. The mean spherical equivalent refractive error at 36 months was -6.5 dioptres (D) (-21.5D to +1.38D) in cryotherapy treated eyes, -2.4D (-13D to +4D) in the laser group, and -0.22D (-9D to +2.25D) in the subthreshold group. Eyes within the treated groups were more myopic than the eyes within the spontaneously regressed group (p = 0.005). At 36 months, 42 out of the 85 infants (that is, 49%) had strabismus (44% in the cryotherapy group, 26% in the laser group, and 25% in the subthreshold group). There was a statistically significant association between the presence of strabismus and anisometropia (p = 0.016) and strabismus and intraventricular haemorrhage (IVH) (p = 0.005). There was a statistically significant difference in the incidence of strabismus between mild and moderate and severe grade IVH (p = 0.01). Eight out of 40 eyes in the cryotherapy group and six out of the 81 eyes in the laser group developed macular ectopia. None of the eyes in the spontaneously regressed group had macular dragging.

CONCLUSIONS

In this study, the grating acuity at 6 months was a good predictor of the 3 year optotype acuity in all groups. Eyes with spontaneously regressed subthreshold stage 3 ROP were associated with better vision at 3 years of age and a lesser degree of myopia compared to the treated groups. Strabismus developed predominantly in the treated groups and was frequently associated with neurological damage and/or anisometropia. The spontaneously regressed subthreshold stage 3 group had a better anatomical outcome compared to the groups in which the retinopathy regressed following treatment.

Betamimetics for inhibiting preterm labour

BACKGROUND

Preterm birth is a major contributor to perinatal mortality and morbidity worldwide. Tocolytic agents are drugs used to inhibit uterine contractions. The most widely used tocolytic agents are betamimetics especially in resource-poor countries.

OBJECTIVES

To assess the effects of betamimetics given to women with preterm labour.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (May 2003) without language restrictions.

SELECTION CRITERIA

Randomised controlled trials of betamimetics, administered by any route or any dose, in the treatment of women in preterm labour where betamimetics are compared with other betamimetics, placebo or no treatment.

DATA COLLECTION AND ANALYSIS

Two reviewers evaluated independently methodological quality and extracted the data. We sought additional information to enable assessment of methodology and conduct intention-to-treat analyses. We present the results using the relative risk for categorical data and the weighted mean difference for continuous data.

MAIN RESULTS

Eleven randomised controlled trials, involving 1332 women, compared betamimetics with placebo. Betamimetics decreased the number of women in preterm labour giving birth within 48 hours (relative risk (RR) 0.63; 95% confidence interval (CI) 0.53 to 0.75) but there was no decrease in the number of births within seven days after carrying out a sensitivity analysis of studies with adequate allocation of concealment. No benefit was demonstrated for betamimetics on perinatal death (RR 0.84; 95% CI 0.46 to 1.55, 7 trials, n = 1332), or neonatal death (RR 1.00; 95% CI 0.48 to 2.09, 5 trials, n = 1174). No significant effect was demonstrated for respiratory distress syndrome (RR 0.87; 95% CI 0.71 to 1.08, 8 trials, n = 1239). A few trials reported the following outcomes, with no difference detected: cerebral palsy, infant death and necrotizing enterocolitis. Betamimetics were significantly associated with the following: withdrawal from treatment due to adverse effects; chest pain; dyspnoea; tachycardia; palpitation; tremor; headaches; hypokalemia; hyperglycemia; nausea/vomiting; and nasal stuffiness; and fetal tachycardia. Other betamimetics were compared with ritodrine in five trials (n = 948). Trials were small, varied and of insufficient quality to delineate any consistent patterns of effect.

REVIEWERS' CONCLUSIONS

Betamimetics help to delay delivery for women transferred to tertiary care or completed a course of antenatal corticosteroids. However, multiple adverse effects must be considered. The data are too few to support the use of any particular betamimetics.

Concentrations of cardiac troponin T in neonates with and without respiratory distress

AIMS

To establish a practical postnatal reference range for cardiac troponin T in neonates and to investigate concentrations in neonates with respiratory distress.

METHODS

Prospective investigation in a tertiary neonatal unit, recruiting infants with and without respiratory distress (sick and healthy infants respectively). Concentrations of cardiac troponin T were compared between sick and healthy infants, accounting for confounding variables.

RESULTS

A total of 162 neonates (113 healthy and 49 sick infants) had samples taken. The median (interquartile range) cardiac troponin T concentration in the healthy infants was 0.025 (0.01-0.062) ng/ml, and the 95th centile was 0.153 ng/ml. There were no significant relations between cardiac troponin T and various variables. The median (interquartile range) cardiac troponin T concentration in the sick infants was 0.159 (0.075-0.308) ng/ml. This was significantly higher (p < 0.0001) than in the healthy infants. In a linear regression model, the use of inotropes and oxygen requirement were significant associations independent of other basic and clinical variables in explaining the variation in cardiac troponin T concentrations.

CONCLUSIONS

Cardiac troponin T is detectable in the blood of many healthy neonates, but no relation with important basic and clinical variables was found. Sick infants have significantly higher concentrations than healthy infants. The variations in cardiac troponin T concentration were significantly associated with oxygen requirement or the use of inotropic support in a regression model. Cardiac troponin T may be a useful marker of neonatal and cardiorespiratory morbidity.

Atypical chronic lung disease in preterm infants

An atypical pattern of chronic lung disease (CLD) has been described in preterm infants and a potential association with intrauterine inflammation has been proposed. We aimed to describe patterns of CLD, to determine the incidence of atypical CLD, and to compare the distribution of various perinatal factors in infants with classic and atypical CLD. Information about demographics, respiratory status and various perinatal variables was collected for all neonatal admissions <1250 g. CLD was defined as oxygen dependency at 28 days of age. Ninety (51%) survivors at 28 days of age developed CLD; of these 37 (41%) were classified as atypical CLD. Factors significantly and independently associated with development of atypical CLD included being inborn, receiving natural surfactant, fewer days of mechanical ventilation within the first 28 days of life and higher birthweight. Chorioamnionitis, postnatal infection and symptomatic PDA were not found to be significantly associated with atypical CLD. Atypical CLD is a common pattern of prolonged oxygen dependency in preterm survivors and is a feature of larger, more mature babies. Our findings do not support the hypothesis that exposure to intrauterine inflammation is an important aetiological factor in the development of atypical CLD.

Right ventricular volume measurements in ventilated preterm neonates

Pulmonary hypertension is associated with worse perinatal outcomes in infants with respiratory disorders. In these infants, right ventricular dysfunction may result in poor pulmonary blood flow. The objective of this study was to follow changes in right ventricular volumes during the first 2 days of life in infants with respiratory distress syndrome. Serial echocardiographic examinations were performed on days 0-2 on infants ventilated for respiratory distress syndrome. Two-dimensional echocardiography with the ellipsoid approximation was used to calculate systolic and diastolic volumes. In 17 ventilated preterm infants, right ventricular volumes were significantly lower on day 2 compared with day 0 and decreased from a median (interquartile range) end systolic volume of 0.80 ml/kg (0.66-0.91 ml/kg) to 0.45 ml/kg (0.39-0.54 ml/kg) ( p < 0.001). End diastolic volume decreased from a median (interquartile range) of 1.54 ml/kg (1.44-1.65 ml/kg) to 1.30 ml/kg (1.22-1.60 ml/kg) ( p = 0.039). Right ventricular ejection fraction increased from a median (interquartile range) of 0.48 ml/kg (0.44-0.56 ml/kg) to 0.62 ml/kg (0.58-0.71 ml/kg) during the same period ( p < 0.001), as did right ventricular output from a median (interquartile range) 120 ml/kg/min (96-125 ml/kg/min) to 140 ml/kg/min (113-168 ml/kg/min) ( p = 0.044). Right ventricular volume decreases during the first 2 days of life in ventilated preterm infants. However, right ventricular performance is maintained.

Recent advances in diagnosis and management of pulmonary hypertension in chronic lung disease

Pulmonary hypertension with elevated pulmonary vascular resistance is a common cardiovascular complication associated with increased morbidity and mortality in preterm infants with chronic lung disease. Injury to the developing pulmonary circulation results in structural and functional abnormalities of the pulmonary vasculature. Animal studies have demonstrated that disruption of angiogenesis may contribute to the failure of normal alveolarisation in chronic lung disease. Levels of vascular endothelial growth factor in bronchoalveolar lavage fluid are lower in infants with chronic lung disease compared to preterm controls. Supplemental oxygen is commonly used to prevent and treat pulmonary hypertension, although optimal arterial oxygen saturation levels remain uncertain. Other vasodilators such as inhaled nitric oxide appear promising, but as yet have not been evaluated in the form of randomised controlled trials. Further studies are required to investigate the long-term effectiveness of pulmonary vasodilator therapy.

Treatment of hypotension in newborns

Systemic hypotension is a common complication of preterm birth affecting approximately one-third of very low-birthweight infants. There is considerable variation between neonatal units in the reported prevalence of hypotension, the threshold for therapeutic intervention and the nature of any cardiovascular support offered. Systemic hypotension is associated with adverse long-term neurodevelopmental outcome. The majority of preterm infants with hypotension have a normal or high left ventricular output, with low systemic vascular resistance often associated with a haemodynamically significant ductal shunt. Historically, volume expansion, dopamine and dobutamine have been the agents most commonly used to treat hypotension. Some hypotensive preterm infants have low cortisol levels, and corticosteroids are being used increasingly to prevent or treat hypotension in these babies.

Quality of care for babies born at 27-28 weeks gestation

Prematurity (birth before 37 completed weeks gestation) accounts for approximately 13% of all livebirths but almost half of all neonatal deaths. There is a close, inverse relationship between survival and gestation: only approximately 1 in 10 babies born at 23 weeks gestation survive to discharge from hospital, whereas at 28 weeks gestation and beyond the situation is reversed with 9 out of 10 babies expected to survive (Lee et al, 2000; Wood et al, 2000).

Evaluation of echocardiography on the neonatal unit

BACKGROUND

Echocardiography is an investigation that is being used increasingly on the neonatal unit. There is some controversy as to whether this service can be provided safely and effectively by neonatologists or whether it should only be performed by paediatric cardiologists.

AIMS

To describe (a) the indications for an echocardiogram, (b) the yield and range of positive findings, (c) the resulting changes in clinical management, and (d) the reliability of echocardiography in the hands of neonatologists when it is performed on the neonatal unit.

METHODS

Information about all echocardiograms performed on the neonatal unit was collected prospectively. Indications for performing echocardiography, echocardiographic findings, and any resulting changes in clinical management were determined. The concordance of findings in infants who underwent echocardiograms performed by both a neonatologist and a paediatric cardiologist was described.

RESULTS

A total of 157 echocardiograms were performed in 82 infants. Echocardiography identified 44 infants with a structural cardiac abnormality and a further 17 infants with a trivial abnormality. In addition, 13 babies were found to have an important functional abnormality. Echocardiography prompted a specific change in clinical management in 64 (78%) babies. In 31 of the 38 infants who had paired scans performed, there was complete concordance between the two examinations. No infants had scans that were completely different. Some discrepancy was identified in seven infants, but this did not prevent appropriate immediate clinical management.

CONCLUSIONS

Echocardiography on the neonatal unit has a high yield for the diagnosis of structural and functional cardiac abnormalities, often results in a change in clinical management, and can be a reliable tool in the hands of neonatologists.

Airway ion transport on the first postnatal day in infants delivered vaginally or by elective cesarean section

To determine airway ion transport in term infants on the first day of postnatal life, and to test the hypothesis that infants born without labor have reduced sodium absorption, we measured nasal potential difference using a modified perfusion protocol suitable for newborn infants. We examined maximal stable baseline potential difference, the change after perfusion with 10(-4) M amiloride (Deltaamil), and the change after perfusion with a zero-chloride solution (Deltazero Cl-) in infants born after elective cesarean section (n = 21) or normal labor (n = 20). Maximal stable baseline potential difference was not different in the two cohorts (-24.0 mV, range -9 to -64 mV versus -25.5 mV, range -6 to -44 mV). The majority of infants in both cohorts showed a substantial fall in potential difference after amiloride perfusion, and there was little capacity for chloride secretion. These results demonstrate a fluid absorptive pattern in the airways on the first postnatal day. In these well infants, the ion transport phenotype was not dependent on the presence or absence of labor.

Risk factors for invasive fungal infection in neonates

Invasive fungal infection is an uncommon, but increasing cause of morbidity and mortality in neonates. There are few controlled studies defining risk factors for the development of fungal infection in a contemporary neonatal population. This retrospective case-control study was undertaken to investigate antenatal, demographic and postnatal variables that may be potentially important in the development of fungal infection. Two gestation-matched controls were identified for each index case. Information about perinatal and demographic variables, as well as important neonatal outcomes, was obtained from case notes. Microbiological data collected included the presence of fungal colonization, and organisms responsible for invasive fungal infection. Over a 5-y period, 24 infants with invasive fungal infection and 48 controls were identified. Candida albicans was the organism identified in 75% of cases of fungal septicaemia, and in all cases complicated by fungal meningitis. Preceding fungal colonization, pulmonary haemorrhage and intrauterine growth restriction were factors significantly and independently associated with invasive fungal infection. Fifty-four percent of infants with invasive fungal infection died, and 82% of survivors developed chronic lung disease.

CONCLUSION

Some new and potentially important risk factors for the development of invasive fungal infection in a contemporary population of infants admitted to a neonatal intensive care were identified.

Measurement of right ventricular volume in healthy term and preterm neonates

BACKGROUND

Pulmonary hypertension is associated with worse perinatal outcomes in infants with respiratory disorders. In such infants right ventricular dysfunction may result in poor pulmonary blood flow.

OBJECTIVE

To evaluate the practicability and repeatability of echocardiographic measurements of right ventricular volume in healthy term and preterm neonates, and to follow changes in right ventricular volume over the first 2 days of life.

METHODS

Serial echocardiographic examinations were performed on day 0, 1, and 2 on healthy term and preterm neonates. Two methods of estimating right ventricular volume were assessed: the ellipsoid approximation and Simpson's stacked discs methods. Systolic and diastolic volumes on days 1 and 2 were compared with baseline values on day 0. Term and preterm volumes were compared at the same time points.

RESULTS

Thirty five infants were recruited, 18 term and 17 preterm. Right ventricular volumes were significantly lower on day 1 and day 2 than baseline in both term and preterm infants. Median (interquartile range) end systolic and diastolic volumes for term infants on days 0, 1, and 2 were 1.04 (0.88-1.44), 0.82 (0.70-1.03), 0.92 (0.72-0.97) ml/kg and 2.21 (2.10-2.75), 2.05 (1.81-2.38), 1.91 (1.81-2.13) ml/kg respectively. In preterm infants the values were 1.09 (0.91-1.16), 0.72 (0.54-0.91), 0.61 (0.54-0.76) ml/kg and 2.09 (1.71-2.25), 1.47 (1.23-1.98), 1.43 (1.22-1.78) ml/kg respectively.

CONCLUSION

Right ventricular volume decreases over the first 2 days of life in healthy term and preterm infants.

Randomised double blind placebo controlled trial of inhaled fluticasone propionate in infants with chronic lung disease

In a double blind randomised controlled trial, 30 infants with chronic lung disease received fluticasone propionate or placebo for one year. There were no significant differences between treatment groups in the incidence of any day or night time symptoms or any other outcome measures.

Right ventricular performance in hypotensive preterm neonates treated with dopamine

Systemic hypotension with left ventricular dysfunction is a common complication of neonatal respiratory distress syndrome and is often treated with inotropic agents. Although pulmonary hypertension with elevated pulmonary vascular resistance is also an important pathophysiological finding in respiratory distress syndrome, the effect of inotropes on the right ventricle has not been studied. The aim of this study was to assess changes in right ventricular dimensions and function with inotropic therapy in hypotensive preterm infants. Hypotensive neonates with respiratory distress syndrome were studied before and 1 hour after the initiation of a dopamine infusion. Right ventricular performance was assessed by two-dimensional echocardiography using the ellipsoid approximation method. Eight hypotensive neonates were recruited with a median (interquartile range) gestation of 27 weeks (26 to 27 weeks). Right ventricular end systolic volume decreased significantly from a median (interquartile range) of 1.06 ml/kg (0.81-1.50 ml/kg) to 0.73 ml/kg (0.51-0.99 ml/kg) (p < 0.01) 1 hour following dopamine therapy. Right ventricular end diastolic volume did not change significantly. Right ventricular ejection fraction increased significantly from 0.36 (0.29-0.46) to 0.51 (0.43-0.53) ( p < 0.01). There was a trend toward an increase in right ventricular output from 90 ml/kg/min (67-115 ml/kg/min) to 112 ml/kg/min-143 ml/kg/min) (p=0.07). Dopamine increases right ventricular ejection fraction through a reduction in right ventricular end systolic volume.

Dependency level of babies on the neonatal unit: a comparison of two different classification systems

BACKGROUND

Monitoring activity on the neonatal unit is important for planning service provision and as part of monitoring quality of care. The dependency level of the patients cared for must be taken into account as well as the number of patients. Two different systems for determining dependency level are in common use.

AIM

To develop a system that would allow the accurate determination of dependency level for babies in our care using both the British Association for Perinatal Medicine and Neonatal Nurses Association definitions and the Northern Neonatal Network definitions and to perform a comparison between these two systems.

METHOD

Forty details relating to current clinical status and treatment being given were recorded daily for every patient on two neonatal units over a 17 month period. These details were recorded in a computer database, and dependency levels were calculated for each patient day using both systems.

RESULTS

A total of 21 905 patient days were recorded for 1555 patients. There was good agreement between the two systems on what constituted the highest level of dependency, but overall comparability was poor, with the two systems assigning comparable dependency levels to only 76% of patient days.

CONCLUSIONS

There is limited comparability in dependency levels between these two widely used systems. There is a need for a standardisation of definitions to allow meaningful comparisons to be made between units.

Percutaneous femoral arterial and venous catheterisation during neonatal intensive care

BACKGROUND

Femoral vessel catheterisation is generally avoided in the neonatal period because of technical difficulties and the fear of complications.

AIM

To review the use of femoral arterial and venous catheters inserted percutaneously on the neonatal intensive care unit.

METHODS

Infants admitted to one of two regional neonatal intensive care units who underwent femoral vessel catheterisation were identified. Information collected included basic details, indication for insertion of catheter, type of catheter and insertion technique, duration of use, and any catheter related complications.

RESULTS

Sixty five femoral catheters were inserted into 53 infants. The median gestational age was 29 weeks (range 23-40). Twenty three femoral arterial catheters (FACs) were inserted into 21 infants and remained in situ for a median of three days (range one to eight). Twelve (52%) FACs remained in place until no longer required, and four (17%) infants developed transient ischaemia of the distal limb. Forty two femoral venous catheters (FVCs) were inserted into 40 infants and remained in situ for a median of seven days (range 1-29). Twenty seven (64%) FVCs remained in place until no longer required, and eight (19%) catheters were removed because of catheter related bloodstream infection.

CONCLUSIONS

FACs and FVCs are useful routes of vascular access in neonates when other sites are unavailable. Complications from femoral vessel catheterisation include transient lower limb ischaemia with FACs and catheter related bloodstream infection.

Neurodevelopmental outcome in high-risk preterm infants treated with inhaled nitric oxide

Inhaled nitric oxide (iNO) is used to treat preterm infants with hypoxaemic respiratory failure. In this study we describe the long-term survival and neurodevelopmental status of high-risk preterm infants enrolled into a randomized controlled trial of iNO therapy. Information regarding long-term outcome was available for all 25 children enrolled in the original trial who survived until discharge from hospital. Formal, blinded, developmental assessment and neurological examinations were performed in 21 out of 22 children still alive at 30 mo of age, corrected for prematurity. No significant differences were found in long-term mortality (12/20 vs 8/22, RR 1.65, 95% CI 0.87-3.3), neurodevelopmental delay (4/7 vs 9/14, RR 0.89, 95% CI 0.37-1.75), severe neurodisability (0/7 vs 5/14, p = 0.12) or cerebral palsy (0/7 vs 2/14, p = 0.53) between iNO-treated and control infants.

CONCLUSION

In this study there was no evidence of a significant effect on either survival or long-term neurodevelopmental status in infants treated with iNO.

Cardiac troponin T in cord blood

BACKGROUND

Perinatal asphyxia is associated with cardiac dysfunction. This may be secondary to myocardial ischaemia. Cardiac troponin T is the ideal marker for myocardial necrosis. Elevated levels in cord blood may be associated with intrauterine hypoxia and increased perinatal morbidity.

AIMS

To establish an upper limit of normal for cardiac troponin T concentration in the cord blood of infants. Relations between cardiac troponin T levels and other variables were investigated.

METHODS

Cord blood samples were collected from 242 infants and analysed. Data on gestation, birth weight, sex, Apgar scores, respiratory status, and mode of delivery were recorded.

RESULTS

A total of 242 samples were collected, and 215 samples from infants without respiratory distress were used to establish the 95th percentile of 0.050 ng/ml. The gestation of these infants ranged from 31 to 42 weeks and birth weight ranged from 1.4 to 5 kg. There were no relations between cardiac troponin T levels and the other variables in these healthy infants. Twenty seven infants developed respiratory symptoms requiring oxygen and/or ventilation. These infants had significantly higher cord cardiac troponin T levels than their healthy counterparts (median (interquartile range) 0.031 (0.010-0.084) v 0.010 (0.010-0.014) ng/ml respectively; p < 0.001).

CONCLUSIONS

Cardiac troponin T levels in the cord blood are unaffected by gestation, birth weight, sex, or mode of delivery. Infants with respiratory distress had significantly higher cord cardiac troponin T levels, suggesting that cardiac troponin T may be a useful marker for myocardial damage in neonates.

Respiratory syncytial virus infection in high risk infants and the potential impact of prophylaxis in a United Kingdom cohort

BACKGROUND

Bronchiolitis caused by respiratory syncytial virus (RSV) is an important cause of morbidity in ex-premature infants. In a randomised placebo controlled trial monoclonal antibody prophylaxis showed a 55% reduction in relative risk of hospital admission for these high risk infants, against a background incidence of 10.6 admissions per 100 high risk infants.

AIMS

To follow a cohort of high risk infants in order to assess hospitalisation rate from RSV and the potential impact of prophylaxis for these patients in a UK local health authority.

METHODS

A cohort of high risk infants from a local health authority were followed over the 1998/99 and 1999/2000 RSV seasons. The high risk population was defined as infants who, at the beginning of the seasons studied, were: (1) under 6 months old and born prior to 36 weeks gestation with no domiciliary oxygen requirement; or (2) under 24 months of age and discharged home in supplemental oxygen. All admissions with bronchiolitis during the season were identified.

RESULTS

A total of 370 high risk infants were identified for the 1998/99 season and 286 for the following year. Over the two years there were 68 admissions. Significantly more admissions occurred from group 2 infants. RSV was identified in 27 cases (four admissions per hundred high risk infants). Prophylaxis may have saved up to pound 195,134 in hospital costs over the two years, but would have cost pound 1.1 million in drug acquisition costs.

CONCLUSIONS

Careful consideration of risk factors is needed when selecting infants for RSV prophylaxis.

A comparison of indices of respiratory failure in ventilated preterm infants

AIM

To compare indices of respiratory failure in terms of their ability to predict adverse respiratory outcomes in preterm infants. The indices evaluated were: (a) the alveolar-arterial oxygen tension difference (A-aDO(2)); (b) the ratio of arterial to alveolar oxygen tension (a/A ratio); (c) the oxygenation index (OI); (d) the fractional inspired oxygen concentration (FIO(2)).

METHODS

Details of respiratory support and arterial blood gas data in the first 24 hours of life were collected in ventilated infants below 34 weeks gestation. The worst single value of a particular index in the first 24 hours was chosen to quantify the severity of respiratory failure in each infant. Receiver operating characteristic curves were constructed and areas under the curve (AUC) calculated to compare the performance of the indices in predicting death from respiratory failure and/or the development of chronic lung disease (CLD).

RESULTS

A total of 155 preterm infants were studied, of whom 35 (23%) died primarily from respiratory failure and 53 of the 120 survivors (44%) developed CLD. The overall performance of the four indices in predicting death from respiratory failure ranged from 0. 77 (AUC for maximum FIO(2)) to 0.88 (AUC for minimum a/A ratio). The corresponding AUCs for gestational age and birth weight were 0.75 and 0.76 respectively. In contrast, demographic variables tended to perform better than indices of respiratory failure in predicting CLD/death.

CONCLUSIONS

There was no evidence of a significant difference between the performance of the a/A ratio, A-aDO(2), and OI in predicting adverse respiratory outcomes. Use of the OI is recommended because of its ease of calculation.

Changes in pulmonary arterial pressure in preterm infants with chronic lung disease

BACKGROUND

Pulmonary arterial pressure (PAP) is raised in preterm infants with respiratory distress syndrome who subsequently develop chronic lung disease. The natural history of pulmonary hypertension in infants with chronic lung disease is unknown.

OBJECTIVES

To investigate changes in PAP, assessed non-invasively using Doppler echocardiography, in infants with chronic lung disease during the 1st year of life.

METHODS

Serial examinations were performed in infants with chronic lung disease and healthy preterm infants. The Doppler derived acceleration time to right ventricular ejection time ratio (AT/RVET) was calculated from measurements made from the pulmonary artery velocity waveform.

RESULTS

A total of 248 examinations were performed in 54 infants with chronic lung disease and 44 healthy preterm infants. The median AT/RVET was significantly lower in infants with chronic lung disease than in healthy preterm infants (0.31 v 0.37). AT/RVET significantly correlated with age corrected for prematurity in both infants with chronic lung disease (r = 0.67) and healthy infants (r = 0.55). There was no significant difference between the rate of change in AT/RVET between the two groups. In infants with chronic lung disease, multivariate analysis showed that AT/RVET was significantly independently associated with age and inversely with duration of supplemental oxygen treatment. Median AT/RVET was significantly lower in infants with chronic lung disease until 40-52 weeks of age corrected for prematurity.

CONCLUSIONS

Although PAP falls with increasing age in both infants with chronic lung disease and healthy preterm infants, it remains persistently raised in infants with chronic lung disease until the end of the 1st year of life.

Dopamine versus dobutamine for hypotensive preterm infants

BACKGROUND

Inotropes are widely used in preterm infants to treat systemic hypotension. The most commonly used drugs are dopamine and dobutamine. These agents have different modes of action which may result in different haemodynamic effects.

OBJECTIVES

To compare the effectiveness and safety of dopamine and dobutamine in the treatment of systemic hypotension in preterm infants.

SEARCH STRATEGY

The standard search method of the Cochrane Neonatal Review Group was used. Searches of electronic and other databases were performed. Previous reviews were searched for references to relevant trials and leading authors in the field were contacted for information about other published and unpublished studies.

SELECTION CRITERIA

Randomised controlled trials where short and/or long term effects of treatment with dopamine and dobutamine for the treatment of systemic arterial hypotension were compared were selected for this review. Trials studying newborn infants born before 37 completed weeks gestation and less than 28 days of age were eligible for inclusion. Systemic arterial hypotension was not defined specifically, but accepted as defined in individual studies. Studies were not limited by birthweight, lower gestational age threshold or by route or duration of administration of inotropic agents. Study quality and eligibility were assessed independently by each reviewer.

DATA COLLECTION AND ANALYSIS

The standard method of the Cochrane Collaboration described in the Cochrane Collaboration Handbook was used to perform this systematic review. Data extraction was performed independently by each reviewer, with differences being resolved by discussion. The following outcomes were determined: mortality in the neonatal period, long term neurodevelopmental outcome, radiological evidence of severe neurological injury, short term haemodynamic changes and incidence of adverse effects. The effect of interventions is expressed either as Relative Risk (RR), Risk Difference (RD) or as Weighted Mean Difference (WMD) with their 95% Confidence Interval (CI).

MAIN RESULTS

Four trials met the pre-defined criteria for inclusion in this review. There was no evidence of a significant difference between dopamine and dobutamine in terms of neonatal mortality (RD 0.02 95% CI -0.12 to 0.16), incidence of periventricular leukomalacia (RD -0.08, 95% CI -0.19 to 0.04), or severe periventricular haemorrhage (RD -0.02, 95% CI -0.13 to 0.09). Dopamine was more successful than dobutamine in treating systemic hypotension, with fewer infants having treatment failure (RD -0.29, 95% CI -0.42 to -0.17; NNT = 3.5, 95% CI 2.4 to 5.9). There was no evidence of a significant difference in change in left ventricular output when dopamine was compared with dobutamine (WMD -83 ml/kg/min, 95% CI -174 to 8 ml/kg/min). There was no evidence of a significant difference between the two agents with respect to the incidence of tachycardia (RD -0.06, 95% CI -0.25 to 0.14). None of the studies reported the incidence of adverse long term neurodevelopmental outcome.

REVIEWER'S CONCLUSIONS

Dopamine is more effective than dobutamine in the short term treatment of systemic hypotension in preterm infants. There was no evidence of an effect on the incidence of adverse neuroradiological sequelae (severe periventricular haemorrhage and/or periventricular leucomalacia), or on the incidence of tachycardia. However, in the absence of data confirming long term benefit and safety of dopamine compared to dobutamine, no firm recommendations can be made regarding the choice of drug to treat hypotension.

Administration of inhaled medication via a tracheostomy in infants with chronic lung disease of prematurity

Four cases of infants with chronic lung disease of prematurity in whom a tracheostomy was performed for acquired subglottic stenosis are reported. The feasibility of administration of inhaled drugs and supplemental oxygen are discussed.

Pulmonary artery pressure: early predictor of chronic lung disease in preterm infants

AIM

To determine if pulmonary artery pressure (PAP) in ventilated preterm infants is independently associated with the development of chronic lung disease (CLD) and whether early assessment has any prognostic value.

METHODS

Two cohorts (development n = 55; and validation n = 28) of preterm infants were studied at 24 hours of age. PAP was assessed non-invasively using its inverse correlation with the corrected acceleration time to right ventricular ejection time ratio (AT:RVET(c)), calculated from the pulmonary artery Doppler waveform. Clinical and respiratory variables were also collected. Using logistic regression analysis to identify factors independently associated with CLD, a prognostic score was developed to predict CLD. The ability of the score to predict CLD was described using receiver operating characteristic (ROC) curves.

RESULTS

Birthweight, inspired oxygen concentration, and AT:RVET(c) were independently predictive of CLD. The area under the ROC curve was 0.96 for the development and 0.89 for the validation cohort. Exclusion of AT:RVET(c) resulted in a reduction to 0.88 and 0.73, respectively.

CONCLUSION

PAP is independently associated with CLD. An early assessment of PAP using AT:RVET(c) may permit the early prediction of CLD as part of a multifactorial scoring system.

Open randomised controlled trial of inhaled nitric oxide and early dexamethasone in high risk preterm infants

AIM

To determine whether treatment with inhaled nitric oxide (NO) and/or dexamethasone reduces the incidence of chronic lung disease (CLD) and/or death in high risk preterm infants.

METHODS

Infants below 32 weeks of gestation were recruited at 96 hours of age if they were deemed to be at high risk of developing CLD. Infants were randomly assigned to one of four treatment groups using a factorial design: (1) 5-20 parts per million inhaled NO for 72 hours; (2) 0.5-1 mg/kg/day intravenous dexamethasone for 6 days; (3) both drugs together; (4) continued conventional management.

RESULTS

Forty two infants were randomised: 10 infants received inhaled NO alone; 11 dexamethasone alone; 10 both treatments; and 11 neither treatment. There was no difference in the combined incidence of CLD and/or death before discharge from hospital between either infants treated with inhaled NO and controls (RR 1.05, 95% CI 0.84-1.25), or those treated with dexamethasone and controls (RR 0.95, 95% CI 0.79-1.18).

CONCLUSIONS

At 96 hours of age, neither treatment with inhaled NO nor dexamethasone prevented CLD or death.

Changes in oxygenation and pulmonary haemodynamics in preterm infants treated with inhaled nitric oxide

AIM

To investigate changes in various cardiorespiratory variables with inhaled nitric oxide (NO), as part of a randomised controlled trial.

METHODS

Infants were treated with inhaled NO for 72 hours. Changes in oxygenation were assessed using the oxygenation index (OI). Serial changes in pulmonary artery pressure (PAP) were assessed using the Doppler derived acceleration time to right ventricular ejection time ratio (AT:RVET). Doppler measurements of right ventricular output, pulmonary blood flow, and systolic PAP was performed in a subset of infants.

RESULTS

Twenty infants received inhaled NO and 22 acted as controls. Infants were treated at a median dose of 5 (range 5 to 20) ppm. There was a fall in median OI by 17% in treated infants within 30 minutes of treatment. The fall in OI in treated infants was significantly different from the response in controls until 96 hours. Infants treated with inhaled NO showed a rapid response with a median rise in AT:RVET of 0.04 (range -0.06 to 0.12) within 30 minutes. The change in AT:RVET was significantly different from controls until 4 hours. Median systolic PAP also fell in treated infants by 6.1 (range -14.4 to -4.4) mm Hg within 1 hour. Changes in OI were significantly associated with changes in PBF (r = 0.44), but not with changes in AT:RVET.

CONCLUSION

Treatment with inhaled NO rapidly improves oxygenation and lowers PAP in preterm infants. However, these effects are transient and treatment does not influence long term outcome.