Diaphragmatic electromyography during a spontaneous breathing trial to predict extubation failure in preterm infants.

BACKGROUND: Premature attempts at extubation and prolonged episodes of ventilatory support in preterm infants have adverse outcomes. The aim of this study was to determine whether measuring the electrical activity of the diaphragm during a spontaneous breathing trial (SBT) could predict extubation failure in preterm infants. METHODS: When infants were ready for extubation, the electrical activity of the diaphragm was measured by transcutaneous electromyography (EMG) before and during a SBT when the infants were on endotracheal continuous positive airway pressure. RESULTS: Forty-eight infants were recruited (median (IQR) gestational age of 27.2 (25.6-30.4) weeks). Three infants did not pass the SBT and 13 failed extubation. The amplitude of the EMG increased during the SBT [2.3 (1.5-4.2) versus 3.5 (2.1-5.3) µV; p < 0.001]. In the whole cohort, postmenstrual age (PMA) was the strongest predictor for extubation failure (area under the curve (AUC) 0.77). In infants of gestational age <29 weeks, the percentage change of the EMG predicted extubation failure with an AUC of 0.74 while PMA was not associated with the outcome of extubation. CONCLUSIONS: In all preterm infants, PMA was the strongest predictor of extubation failure; in those born <29 weeks of gestation, diaphragmatic electromyography during an SBT was the best predictor of extubation failure. IMPACT: Composite assessments of readiness for extubation may be beneficial in the preterm population. Diaphragmatic electromyography measured by surface electrodes is a non-invasive technique to assess the electrical activity of the diaphragm. Postmenstrual age was the strongest predictor of extubation outcome in preterm infants. The change in diaphragmatic activity during a spontaneous breathing trial in extremely prematurely born infants can predict subsequent extubation failure with moderate sensitivity and specificity.

Risk assessment of survival and morbidity of infants born at <24 completed weeks of gestation.

BACKGROUND: Infants born at the threshold of viability have a high risk of mortality and morbidity. The British Association of Perinatal Medicine (BAPM) provided updated guidance in 2019 advising a risk-based approach to balancing decisions about active versus redirected care at birth. AIMS: To determine survival and morbidity of infants born between 22 and 24 completed weeks of gestation. To develop a scoring system to categorise infants at birth according to risk for mortality or severe adverse outcome. METHODS: A retrospective, single centre observational study of infants who received neonatal care from 2011 to 2021. Data were collected on mortality, morbidity and two-year neurodevelopmental outcomes. Each infant was risk categorised utilising the proposed tools in the BAPM (2019) framework. A composite adverse score for either dying or surviving with severe impairment was created. RESULTS: Four infants born at 22 weeks, 49 at 23 weeks and 105 at 24 weeks of gestation were included. The mortality rate was 23.4 %. Following risk categorisation there were 8 (5.1 %) extremely high risk, 44 (27.8 %) high risk and 106 (67.1 %) moderate risk infants. The rate of dying or surviving with severe impairment for extremely high risk, high risk and moderate risk were 100 %, 88.9 % and 53 % respectively. The proportions with the composite adverse outcome differed significantly according to the risk category (p < 0.001). CONCLUSIONS: When applying a scoring system to risk categorise infants at birth, high rates of dying or surviving with severe impairment were found in infants born at 22 or 23 weeks of gestation.