Evidence based care of the very preterm infant : studies on thermal care and breastfeeding in Europe

Very preterm birth occurs in approximately 1.5% of all births in Europe. Advances in neonatal intensive care has contributed to a decline in mortality and morbidity, nevertheless very preterm birth (birth before 32 weeks of gestation) is one of the main determinants of infant mortality and shortand long-term morbidity in Europe. Both the early thermal care after delivery and the availability of breast milk and breastfeeding during neonatal care are two areas of importance for morbidity and mortality for the very preterm infant. The objective of the European collaboration project, Effective Perinatal Care in Europe (EPICE) is to investigate if evidence-based medicine is translated into care in the obstetric and neonatal intensive care units (NICU) caring for very preterm infants. During 2011-2012, perinatal data at an individual level (cohort study) and unit level (unit study) were collected for infants born before 32 weeks of gestation in 19 regions in 11 countries in Europe, of which Stockholm is one of the regions. Paper I is based on EPICE cohort data, paper II and IV on EPICE cohort and unit data, and paper III on cohort data from the Stockholm region. Paper I investigated the incidence of hypothermia (temperature <36.5°C) at admission to neonatal care and its association with morbidity, overall mortality, and mortality stratified by time of death during neonatal care. Paper II investigated hypothermia prevention strategies after very preterm birth and the association between reported use of prevention strategy and admission temperature to the NICU. Paper III included data from the Stockholm region and examined if early and high intake of mother's own milk and other predictors of breastfeeding were positively related to breast milk feeding near full term age (postmenstrual age (PMA) 36-40 weeks) (PMA= gestational age plus postnatal age), and paper IV studied breast milk feeding rates at discharge and individual and unit factors that might facilitate breast milk feeding at discharged from NICU. Paper I showed that hypothermia after very preterm birth is common in European settings, more than 50% of infants admitted to the NICU had a temperature below 36.5°C. Infants who had a temperature below 35.5°C had a twofold risk of mortality during the first month of life in comparison with normothermic (36.5-37.5°C) infants. Paper II showed that in units reporting systematic use of hypothermia prevention the incidence of hypothermia at admission was 54% and in units reporting no systematic use (sometimes or in infants <28 weeks/1000g) it was 75%. In adjusted analysis of no systematic use of hypothermia prevention with systematic use as reference group, the odds ratio of hypothermia at admission was 2.19, 95% CI (1.47-3.24). Hyperthermia was seen in 4.8% of all infants admitted to NICU. In paper III 80% of the infants in the Stockholm region received breast milk at 36 weeks PMA (55% exclusively and 25% partially). High provision of mother’s own milk was associated with exclusive breast milk feeding at discharge. Between PMA 36 and 40 weeks, breast milk feeding decreased overall, but this decrease was not associated with investigated predictors. Among infants receiving exclusive breast milk feeding at 40 weeks PMA, 76% were breastfed directly from the breast. Paper IV showed large variations in breast milk feeding rates at discharge across the regions in Europe (36-80%). Mother’s own milk, compared to donor milk or formula, at first enteral feed was associated with exclusive breast milk feeding at discharge from the NICU. Infants in units with a Baby Friendly Hospital initiative (BFHI) accreditation were more likely to receive any maternal milk at discharge. In units that used donor milk in the neonatal period, infants were more likely to be exclusively breast milk fed at discharge from NICU. The proportion of breastfeeding directly from the breast varied between the regions (16-93%). In conclusion, hypothermia at admission is common among infants born very preterm despite availability evidence-based hypothermia preventing strategies. Temperatures <35.5°C at admission were strongly associated with increased mortality. This calls for emphasizing hypothermia prevention and monitoring of the infant’s temperature already in the delivery room. Large variations in breastfeeding at discharge were seen between the EPICE regions. Early breastfeeding support improved breast milk feeding at discharge. This illustrates the potential and the key role the NICU has in improving breastfeeding rates after very preterm birth. The overall conclusion is that there is room for improvement in thermal care and breastfeeding after very preterm birth across neonatal units in Europe. LIST OF SCIENTIFIC PAPERS This thesis is based on the following papers. The papers will be referred to by their Roman numerals (1-IV) I. Emilija Wilson, Rolf F Maier, Mikael Norman, Bjoern Misselwitz, Elizabeth A Howell, Jennifer Zeitlin, Anna-Karin Edstedt Bonamy on behalf of the Effective Perinatal Intensive Care in Europe (EPICE) Research Group. Admission hypothermia in very preterm infants and neonatal mortality and morbidity. The Journal of Pediatrics 2016; 175:61-7. II. Emilija Wilson, Jennifer Zeitlin, Aurélie Piedvache, Bjoern Misselwitz, Kyllike Christensson, Rolf F Maier, Mikael Norman, Anna-Karin Edstedt Bonamy, and the EPICE Research Group. Strategies to prevent hypothermia in the delivery room after very preterm birth: results from the EPICE study. Manuscript. III. Emilija Wilson, Kyllike Christensson, Lena Brandt, Maria Altman, AnnaKarin Edstedt Bonamy. Early provision of mother’s own milk and other predictors of successful breast milk feeding after very preterm birth: a regional observational study. Journal of Human Lactation 2015; 31:393-400. IV. Emilija Wilson, Anna-Karin Edstedt Bonamy, Mercedes Bonet, Liis Toome, Carina Rodrigues, Elizabeth A Howell, Marina Cuttini, Jennifer Zeitlin, and the EPICE Research Group. Room for improvement in breast milk feeding after very preterm birth in Europe ˗ results from the EPICE cohort. Submitted. CONTENTS