Population study of neurodevelopmental outcomes of extremely premature infants admitted after office hours

Variation in hospital morbidities in an Australian neonatal intensive care unit network

OBJECTIVE

There is an expectation among the public and within the profession that the performance and outcome of neonatal intensive care units (NICUs) should be comparable between centres with a similar setting. This study aims to benchmark and audit performance variation in a regional Australian network of eight NICUs.

DESIGN

Cohort study using prospectively collected data.

SETTING

All eight perinatal centres in New South Wales and the Australian Capital Territory, Australia.

PATIENTS

All live-born infants born between 23⁺⁰ and 31⁺⁶ weeks gestation admitted to one of the tertiary perinatal centres from 2007 to 2020 (n=12 608).

MAIN OUTCOME MEASURES

Early and late confirmed sepsis, intraventricular haemorrhage, medically and surgically treated patent ductus arteriosus, chronic lung disease (CLD), postnatal steroid for CLD, necrotising enterocolitis, retinopathy of prematurity (ROP), surgery for ROP, hospital mortality and home oxygen.

RESULTS

NICUs showed variations in maternal and neonatal characteristics and resources. The unadjusted funnel plots for neonatal outcomes showed apparent variation with multiple centres outside the 99.8% control limits of the network values. The hierarchical model-based risk-adjustment accounting for differences in patient characteristics showed that discharged home with oxygen is the only outcome above the 99.8% control limits.

CONCLUSIONS

Hierarchical model-based risk-adjusted estimates of morbidity rates plotted on funnel plots provide a robust and straightforward visual graphical tool for presenting variations in outcome performance to detect aberrations in healthcare delivery and guide timely intervention. We propose using hierarchical model-based risk adjustment and funnel plots in real or near real-time to detect aberrations and start timely intervention.

Global prevalence of long-term neurodevelopmental impairment following extremely preterm birth: a systematic literature review

Objective

Neurodevelopmental impairment (NDI) is a major complication of extreme prematurity. This systematic review was conducted to summarize the worldwide long-term prevalence of NDI associated with extreme prematurity.

Methods

Embase and MEDLINE databases were searched for epidemiologic and observational/real-world studies, published in English between 2011 and 2016, reporting long-term prevalence of NDI (occurring from 1 year) among extremely preterm infants born at gestational age (GA) ≤28 weeks.

Results

Of 2406 articles identified through searches, 69 met the protocol NDI definition (24 North America, 25 Europe, 20 Rest of World). Prevalence of any severity NDI in North America was 8%–59% at 18 months to 2 years, and 11%–37% at 2–5 years; prevalence of moderate NDI in Europe was 10%–13% at 18 months to 2 years, 3% at 2–5 years, and 9%–19% at ≥5 years; prevalence of any NDI in Rest of World was 15%–61% at 18 months to 2 years, and 42% at 2–5 years (no North America/Rest of World studies reported any NDI at ≥5 years). A trend toward higher prevalence of NDI with lower GA at birth was observed.

Conclusions

Extreme prematurity has a significant long-term worldwide impact on neurodevelopmental outcomes.

Early neurodevelopmental outcomes of congenital gastrointestinal surgical conditions: a single-centre retrospective study

BACKGROUND

Evidence is emerging that surgery in the neonatal period is associated with increased risk of suboptimal neurodevelopmental outcomes (SNDO). The aim of this study was to describe neurodevelopmental outcomes (at 1 year) of neonatal surgery for congenital gastrointestinal surgical conditions (CGSC) and to explore risk factors.

METHODS

Retrospective study (2005-2014) of infants born ≥34 weeks gestation with CGSC and admitted to the surgical neonatal intensive care unit of Perth Children's Hospital, Western Australia. Clinical details and 1-year developmental outcomes based on Griffiths Mental Developmental Assessment Scales were collated from the database and by reviewing the medical records of study infants. SNDO was defined as one or more of the following: a general quotient less than 88 (ie, >1 SD below mean), cerebral palsy, blindness or sensorineural deafness. Univariable and multivariable logistic regression analyses were carried out to explore risk factors for SNDO. A total of 413 infants were included, of which 13 died. Median gestation was 37.6 weeks (IQR: 36.4-39.1). Information on developmental outcomes was available from 262 out of 400 survivors. A total of 43/262 (16.4%) had SNDO. On univariable analysis, lower z scores for birth weight, prolonged duration of antibiotics, increased episodes of general anaesthesia and prolonged duration of hospital stay were associated with SNDO. On multivariable analysis, lower z scores for birth weight and prolonged hospital stay were associated with increased risk of SNDO.

CONCLUSIONS

Late preterm and term infants undergoing neonatal surgery for CGSC may be at risk for SNDO. Studies with longer duration of follow-up are needed to further evaluate the role of potentially modifiable risk factors on their neurodevelopmental outcomes.

Variation in hospital mortality in an Australian neonatal intensive care unit network

BACKGROUND

Studying centre-to-centre (CTC) variation in mortality rates is important because inferences about quality of care can be made permitting changes in practice to improve outcomes. However, comparisons between hospitals can be misleading unless there is adjustment for population characteristics and severity of illness.

OBJECTIVE

We sought to report the risk-adjusted CTC variation in mortality among preterm infants born <32 weeks and admitted to all eight tertiary neonatal intensive care units (NICUs) in the New South Wales and the Australian Capital Territory Neonatal Network (NICUS), Australia.

METHODS

We analysed routinely collected prospective data for births between 2007 and 2014. Adjusted mortality rates for each NICU were produced using a multiple logistic regression model. Output from this model was used to construct funnel plots.

RESULTS

A total of 7212 live born infants <32 weeks gestation were admitted consecutively to network NICUs during the study period. NICUs differed in their patient populations and severity of illness.The overall unadjusted hospital mortality rate for the network was 7.9% (n=572 deaths). This varied from 5.3% in hospital E to 10.4% in hospital C. Adjusted mortality rates showed little CTC variation. No hospital reached the +99.8% control limit level on adjusted funnel plots.

CONCLUSION

Characteristics of infants admitted to NICUs differ, and comparing unadjusted mortality rates should be avoided. Logistic regression-derived risk-adjusted mortality rates plotted on funnel plots provide a powerful visual graphical tool for presenting quality performance data. CTC variation is readily identified, permitting hospitals to appraise their practices and start timely intervention.

24/7 in house attending staff coverage improves neonatal short-term outcomes: A retrospective study

OBJECTIVES

to compare short-term outcomes of newborns over 36 weeks with Apgar scores≤3 at 1min, following the adoption of a 24/7 in house coverage schedule STUDY DESIGN: A retrospective chart review comparing two 12-month epochs. Epoch 1: coverage provided by residents with availability on call at home of attending staff. Epoch 2: On site coverage by attending staff.

RESULTS

71 and 60 charts were reviewed from Epoch 1 and 2 respectively. The number of infants receiving chest compressions was reduced during Epoch 2 (from 19% to 1.6%, p<0.0001). The proportion of infants admitted to the NICU (81% vs 61%, p<0.01), and the median length of stay in hospital (61 vs 48h, p=0.03) were significantly reduced in Epoch 2.

CONCLUSION(S)

Continuous coverage by attending staff decreased the number of admissions to intensive care as well as the duration of hospitalization stay for newborns with low Apgar scores.

Twenty-four-hour in-house neonatologist coverage and long-term neurodevelopmental outcomes of preterm infants

Objectives

To compare short- and long-term neurodevelopmental outcomes at 3 years of corrected age of preterm infants cared for by 24-hour in-house staff neonatologists and those cared for by staff neonatologists during daytime only.

Methods

Retrospective analysis of prospectively collected follow-up data on all nonanomalous preterm infants from 1998 to 2004 excluding year 2001 as a washout period. Infants were divided into two groups based on care provided by staff neonatologists: 24-hour in-house coverage (24-hour coverage 1998-2000) and daytime coverage (day coverage 2002-2004). Short- and long-term outcomes were compared.

Results

A total of 387 (78%) of the screened infants were included. Twenty-four-hour coverage (n=179) and day coverage (n=208) groups had a median birth weight (BW) of 875 g (range 470-1250) and 922 g (480-1530; P=0.028), respectively, and both had a median gestational age of 27 weeks. In the day coverage group, a smaller proportion of mothers had chorioamnionitis (20% vs. 30%; P=0.025), received less antibiotics (62% vs. 73%; P=0.023), and infants had fewer cases of confirmed sepsis (14% vs. 23%; P=0.022). In the day coverage group, a larger number of infants had respiratory distress syndrome (87% vs. 77%; P=0.011) and required prolonged mechanical ventilation (median 31 vs. 21 days; P=0.002). The incidence of major neurodevelopmental impairment was not significantly different between the two groups (odds ratio 0.76; 95% confidence interval 0.34-1.65).

Conclusions

Duration of mechanical ventilation was reduced with 24-hour in-house coverage by staff neonatologists. However, 24-hour coverage was not associated with any difference in neurodevelopmental (ND) outcomes at 3-year corrected age.

Risk of neurodevelopmental impairment for outborn extremely preterm infants in an Australian regional network

OBJECTIVE

To compare neurodevelopmental outcomes at 2-3 years in extremely premature outborn and inborn infants.

DESIGN

Population-based retrospective cohort study.

SETTING

Geographically defined area of New South Wales (NSW) and the Australian Capital Territory (ACT) served by a network of 10 neonatal intensive care units (NICUs).

PATIENTS

All premature infants <29 weeks gestation born between 1998 and 2004 in the setting.

INTERVENTION

At 2-3 years, corrected age, 1473 children were assessed with either the Griffiths Mental Developmental Scales (GMDS) or the Bayley Scales of Infant Development (BSID-II).

MAIN OUTCOME MEASURE

Moderate/severe functional disability (FD) defined as: developmental delay (GMDS general quotient (GQ) or BSID-II mental developmental index (MDI)) > 2 standard deviations (SD) below the mean; cerebral palsy (CP) requiring aids; sensorineural or conductive deafness (requiring amplification); or bilateral blindness (visual acuity <6/60 in better eye).

RESULTS

At 2-3 years, moderate/severe functional disability does not appear to be significantly different between outborn and inborn infants (adjusted OR 0.782; 95% CI 0.424-1.443). However, there were a significant number of outborn infants lost to follow up (23.3% versus 42.9%).

CONCLUSION

In this cohort, at 2-3 years follow up neurodevelopmental outcome does not appear to be significantly different between outborn and inborn infants. These results should be interpreted with caution given the limitation of this study.

Neurodevelopmental Outcomes of Premature Infants Treated for Patent Ductus Arteriosus: A Population-Based Cohort Study

OBJECTIVE

To compare neurodevelopmental outcomes of extremely preterm infants diagnosed with patent ductus arteriosus (PDA) who were treated medically or surgically and those who were not diagnosed with PDA or who did not undergo treatment for PDA.

STUDY DESIGN

This retrospective population-based cohort study used data from a geographically defined area in New South Wales and the Australian Capital Territory served by a network of 10 neonatal intensive care units. Patients included all preterm infants born at <29 completed weeks of gestation between 1998 and 2004. Moderate/severe functional disability at 2-3 years corrected age was defined as developmental delay, cerebral palsy requiring aids, sensorineural or conductive deafness (requiring bilateral hearing aids or cochlear implant), or bilateral blindness (best visual acuity of <6/60).

RESULTS

Follow-up information at age 2-3 years was available for 1473 infants (74.8%). Compared with infants not diagnosed with a PDA or who did not receive PDA treatment for PDA, those with medically treated PDA (aOR, 1.622; 95% CI, 1.199-2.196) and those with surgically treated PDA (aOR, 2.001; 95% CI, 1.126-3.556) were at significantly greater risk for adverse neurodevelopmental outcomes at age 2-3 years.

CONCLUSION

Our results demonstrate that treatment for PDA may be associated with a greater risk of adverse neurodevelopmental outcome at age 2-3 years. This was particularly so among infants born at <25 weeks gestation. These results may support permissive tolerance of PDAs; however, reasons for this association remain to be elucidated through carefully designed prospective trials.

Neurodevelopmental outcome of extremely preterm infants born to rural and urban residents' mothers in Australia

BACKGROUND

Rural and remote residents in Australia have long experienced unfavourable health outcomes compared to their urban counterparts.

AIMS

To study neurodevelopmental outcome at 2-3 years of age, corrected for prematurity of extremely preterm infants admitted to a regional neonatal Australian network from rural and urban regions (based on usual location of maternal residence).

METHODS

A multicenter population-based cohort study in which surviving urban and rural infants <29 weeks of gestation born between 1998 and 2004 underwent neurodevelopmental assessment at 2-3 years of age, corrected for prematurity by a developmental assessment team. Moderate/severe functional disability was defined as developmental delay (GQ or MDI>2 SD below the mean), cerebral palsy (aided for walking), sensorineural or conductive deafness (requiring amplification), and bilateral blindness (visual acuity <6/60 in the better eye).

RESULTS

Of the 1970 infants alive at 2-3 years of age, 268 (63.8%) rural and 1205 (77.7%) urban infants were evaluated. Infants lost to follow-up were of slightly higher gestational age and birth weight. Both rural and urban assessed groups were comparable in gestation and birth weight percentile. In comparison to their urban counterparts, the rural group had more outborn infants (19.8% vs. 4.6%, p<0.001). They, however, did not have an increased risk of moderate/severe functional disability (OR 0.77, 95% CI 0.52-1.23, p=0.176). This finding was not significantly altered by limiting the analysis to different gestational ages.

CONCLUSION

Extremely premature surviving young children from rural areas of residence do not seem to have an increased risk for moderate/severe functional disability.

Neurodevelopmental outcomes of preterm singletons, twins and higher-order gestations: a population-based cohort study

OBJECTIVE

To study the neurodevelopmental outcomes of multiple (twins, triplets, quads) compared with singleton extremely preterm infants <29 weeks gestation.

DESIGN

Population-based retrospective cohort study.

SETTING

A network of 10 neonatal intensive care units in a geographically defined area of New South Wales and the Australian Capital territory.

PATIENTS

1473 infants <29 weeks gestation born between 1 January 1998 and 31 December 2004.

INTERVENTION

At 2-3 years of corrected age, a neurodevelopmental assessment was conducted using either the Griffiths Mental Developmental Scales or the Bayley Scales of Infant Development II.

MAIN OUTCOME MEASURE

Moderate-severe functional disability was defined as developmental delay (Griffiths Mental Developmental Scales General Quotient or Bayley Scales of Infant Development-II Mental Development Index >2 SDs below the mean), moderate cerebral palsy (unable to walk without aids), sensorineural or conductive deafness (requiring amplification) or bilateral blindness (visual acuity <6/60 in the better eye).

RESULTS

Of the 1081 singletons and 392 multiples followed-up, singletons demonstrated higher rates of systemic infections, steroid treatment for chronic lung disease and birth weight <10th percentile. Moderate-severe functional disability did not differ significantly between singletons and multiples (15.8% vs 17.6%, OR 1.14; 95% CI 0.84 to 1.54; p=0.464). Further subgroup analysis of twins, higher-order gestations, 1st-born multiples, 2nd or higher-born multiples, same and unlike gender multiples, did not demonstrate statistically higher rates of functional disability compared with singletons.

CONCLUSIONS

Premature infants from multiple gestation pregnancies appear to have comparable neurodevelopmental outcomes to singletons.