Respiratory morbidity at follow-up of small-for-gestational-age infants born very prematurely.

BACKGROUND: The aim of this study was to determine whether small-for-gestational-age (SGA) infants born very prematurely had increased respiratory morbidity in the neonatal period and at follow-up. METHODS: Data were examined from infants recruited into the United Kingdom Oscillation Study (UKOS). Of the 797 infants who were born at <29 wk of gestational age, 174 infants were SGA. Overall, 92% were exposed to antenatal corticosteroids and 97% received surfactant; follow-up data at 22-28 mo were available for 367 infants. RESULTS: After adjustment for gestational age and sex, SGA infants had higher rates of supplementary oxygen dependency at 36 wk postmenstrual age (odds ratio (OR): 3.23; 95% confidence interval: 2.03, 5.13), pulmonary hemorrhage (OR: 3.07; 95% CI: 1.82, 5.18), death (OR: 3.32; 95% CI: 2.13, 5.17), and postnatal corticosteroid requirement (OR: 2.09; 95% CI: 1.35, 3.23). After adjustment for infant and respiratory morbidity risk factors, a lower mean birth weight z-score was associated with a higher prevalence of respiratory admissions (OR: 1.40; 95% CI: 1.03, 1.88 for 1 SD change in z-score), cough (OR: 1.28; 95% CI: 1.00, 1.65), and use of chest medicines (OR: 1.32; 95% CI: 1.01, 1.73). CONCLUSION: SGA infants who were born very prematurely, despite routine use of antenatal corticosteroids and postnatal surfactant, had increased respiratory morbidity at follow-up, which was not due to poor neonatal outcome.

Prematurely born infants' response to resuscitation via an endotracheal tube or a face mask.

BACKGROUND: Prematurely born infants may be resuscitated in the labour suite via a face mask or an endotracheal tube. AIMS: To assess prematurely born infants' initial responses to resuscitation delivered via an endotracheal tube or a face mask, to determine if the first five inflations via an endotracheal tube produced expired tidal volumes greater than 4.4ml/kg (twice the anatomical dead space) and whether the outcome of initial resuscitation via an endotracheal tube or via a face mask differed according to the first active inflation (the infant's inspiratory effort coinciding with an inflation). STUDY DESIGN: Prospective observational study. SUBJECTS: Thirty-five infants (median gestational age 25, range 23-27weeks) requiring resuscitation via an endotracheal tube (n=20) or a face mask (n=15) were studied. OUTCOME MEASURES: Inflation pressures, inflation times, expiratory tidal volumes, end tidal carbon dioxide (ETCO2) and leak were recorded. RESULTS: Before the first active inflation, only 27% of infants receiving resuscitation via an endotracheal tube had expiratory volumes greater than 4.4ml/kg. During, both endotracheal and face mask initial resuscitations, during the first active inflation the expired tidal volumes (7.7ml/kg, 5.2ml/kg) and ETCO2 levels (4.8kPa, 3.2kPa) were significantly higher than during the inflations before the first active inflation (2.8ml/kg, 1.6ml/kg; 0.36kPa, 0.2kPa respectively) (all p<0.001). CONCLUSIONS: Initial resuscitation via an endotracheal tube using currently recommended pressures, rarely produced adequate tidal volumes. Resuscitation via an endotracheal tube or a face mask was most effective when the infant's inspiratory effort coincided with an inflation.

Neuromuscular blockade and lung function during resuscitation of infants with congenital diaphragmatic hernia.

BACKGROUND: There is no consensus or evidence as to whether a neuromuscular blocking agent should be used during the initial resuscitation of infants with congenital diaphragmatic hernia (CDH) in the labour ward. OBJECTIVE: To determine if administration of a neuromuscular blocking agent affected the lung function of infants with CDH during their initial resuscitation in the labour ward. METHODS: Fifteen infants with CDH were studied (median gestational age 38 weeks, range 34-41; birth weight 2,790 g, range 1,780-3,976). Six infants had undergone feto-endotracheal occlusion (FETO). Flow, airway pressure, tidal volume and dynamic lung compliance changes were recorded using a respiratory function monitor (NM3, Respironics). Twenty inflations immediately before, immediately after and 5 min after administration of a neuromuscular blocking agent (pancuronium bromide) were analysed. RESULTS: The median dynamic lung compliance of the 15 infants was 0.22 ml/cm H2O/kg (range 0.1-0.4) before and 0.16 ml/cm H2O/kg (range 0.1-0.3) immediately after pancuronium bromide administration (p < 0.001) and remained at a similar low level 5 min after pancuronium bromide administration. The FETO compared to the non-FETO infants had a lower median dynamic compliance both before (p < 0.0001) and 5 min after pancuronium administration (p < 0.001) and required significantly longer durations of ventilation (p = 0.004), supplementary oxygen (p = 0.003) and hospitalisation (p = 0.007). CONCLUSIONS: Infants with CDH, particularly those who have undergone FETO, have a low lung compliance at birth, and this is further reduced by administration of a neuromuscular blocking agent.