Benefit of antenatal corticosteroids by year of birth among preterm infants in Canada during 2003-2017: a population-based cohort study.

OBJECTIVE: To evaluate the changes in the associations of antenatal corticosteroids (ACS) with neonatal mortality and severe neurological injury over time (2003-17). DESIGN: National, population-representative, retrospective cohort study. SETTING: Level III neonatal intensive care units participating in the Canadian Neonatal Network. POPULATION: All infants born at 230/7 -336/7 weeks of gestation (n = 43 456). METHODS: We estimated the associations between exposure to ACS and neonatal outcomes by year of birth. Year of birth was considered both continuously and categorically as three consecutive epochs. MAIN OUTCOME MEASURE: Neonatal mortality and severe neurological injury. RESULTS: The absolute rates of neonatal mortality and severe neurological injury decreased during the study period in both the ACS and No ACS groups. For infants born at 230/7 -306/7 weeks of gestation, ACS was associated with similar reductions in neonatal mortality across the three epochs (9.0% versus 18.1%, adjusted relative risk [aRR] 0.54, 95% CI 0.47-0.61 in 2003-09; 7.6% versus 19.6%, aRR 0.51, 95% CI 0.44-0.59 in 2010-13; and 7.3% versus 14.5%, aRR 0.56, 95% CI 0.46-0.68 in 2014-17) and in severe neurological injury (13.2% versus 25.8%, aRR 0.57, 95% CI 0.50-0.64 in 2003-09; 7.4% versus 17.4%, aRR 0.53, 95% CI 0.43-0.66 in 2010-14; and 7.2% versus 14.8%, aRR 0.59, 95% CI 0.48-0.74 in 2014-17). CONCLUSION: Despite the ongoing improvements in neonatal care of preterm infants, as reflected by the gradual decrease in the absolute rates of neonatal mortality and severe neurological injury, the association of ACS treatment with neonatal mortality and severe neurological injury among extremely preterm infants born at 23-30 weeks of gestation has remained stable throughout the study period of 15 years. TWEETABLE ABSTRACT: Despite the gradual decrease in the rates of neonatal mortality and severe neurological injury, antenatal corticosteroids remain an important intervention in the current era of neonatal care.

The association of shock index and haemoglobin variation with postpartum haemorrhage after vaginal delivery: a prospective cohort pilot study.

INTRODUCTION: Shock index and continuous non-invasive haemoglobin monitoring (SpHb) have both been proposed for the timely recognition of postpartum haemorrhage (PPH). We sought to determine, in parallel, the association of each of shock index and SpHb with blood loss after vaginal delivery. METHODS: Sixty-six women were recruited to this prospective observational study. Shock index and SpHb were recorded postpartum for 120 min. The association between each of shock index and SpHb with quantitative blood loss (QBL) at 30, 60 and 120 min postpartum was determined using linear mixed models. Area-under-the-receiver-operator-characteristic (AUROC) curves were constructed to evaluate the diagnostic ability of shock index and SpHb to detect PPH (defined as QBL ≥1000 mL). RESULTS: Shock index trend was associated with QBL over the first 30 min (r=0.37, P=0.002), but not over 60 or 120 min. There was an association of SpHb trend with QBL over the first 30 min (P=0.06), but not over 60 min (r=-0.32, P=0.009) or 120 min (r=-0.26, P=0.03). Maximum shock index within 60 min correlated with QBL (r=0.54, P <0.001) and was a predictor of PPH (P=0.0012, AUROC 0.796). Maximum change in SpHb within 60 min negatively correlated with QBL (r=-0.4, P <0.001) and was a predictor of PPH (P=0.048, AUROC 0.761). CONCLUSIONS: The trend of shock index and its peak values are associated with blood loss after vaginal delivery and are early indicators of PPH. Negative trend of SpHb is a late sign of PPH and has a weaker association with blood loss than shock index.

Neonates with hypoxic-ischemic encephalopathy treated with hypothermia: Observations in a large Canadian population and determinants of death and/or brain injury.

BACKGROUND: Birth asphyxia in term neonates remains a serious condition that causes significant mortality and long-term neurodevelopmental sequelae despite hypothermia treatment. The objective of this study was to review therapeutic hypothermia practices in a large population of neonates with hypoxic-ischemic encephalopathy (HIE) across Canada and to identify determinants of adverse outcome. METHODS: Our retrospective observational cohort study examined neonates≥36 weeks, admitted to the Canadian Neonatal Network NICUs between 2010 and 2014, diagnosed with HIE, and treated with hypothermia. Adverse outcome was defined as death and/or brain injury. Maternal, birth, and postnatal characteristics were compared between neonates with adverse outcome and those without. The association between the variables which were significantly different (p < 0.05) between the two groups and adverse outcome were further tested, while adjusting for gestational age, birth weight, gender, and initial severity of encephalopathy. RESULTS: A total of 2187 neonates were admitted for HIE; 52% were treated with hypothermia and 40% developed adverse outcome. Initial severity of encephalopathy (moderate, p = 0.006; severe, p < 0.0001), hypotension treated with inotropes (p = 0.001), and renal failure (p = 0.007) were significantly associated with an increased risk of death and/or brain injury. CONCLUSIONS: In asphyxiated neonates treated with hypothermia, not only their initial severity of encephalopathy on admission, but also their cardiac and renal complications during the first days after birth were significantly associated with risk of death and/or brain injury. Careful monitoring and cautious management of these complications is warranted.