Short-term outcome and complications of therapeutic hypothermia in neonates with moderate-to-severe hypoxic ischaemic encephalopathy: a single-centre retrospective observational study in a hospital in Mumbai, India

Abstract

ABSTRACT Background Although shown to reduce death or disability in moderate-to-severe hypoxic ischaemic encephalopathy (HIE), therapeutic hypothermia (TH) has recently been associated with an increase in adverse events in low- and middle-income countries (LMIC). Aim To determine the clinical characteristics, complications and short-term outcome in neonates receiving TH in King Edward Memorial Hospital, Mumbai, India. Methods A retrospective single-centre study of neonates with moderate-to-severe HIE who received TH from 1 January 2018 to 31 December 2021 was undertaken. TH was provided as per the unit’s protocol using either a servo-controlled device or a phase-changing material (PCM). Results One hundred and fifty-five neonates were included with 94.2% intramural births. Mean gestation and birthweight were 38.6 (1.5) weeks and 2776.7 (431) g, respectively. HIE staging was moderate in 87.1% and severe in 12.9%, with a mean cord pH of 6.93 (0.14) and seizures in 38.7%. Adverse events included shock (50.3%), clinically significant bleeding (16%), acute kidney injury (6.7%), culture-positive sepsis (11.6%), persistent pulmonary hypertension (9%), bradycardia (9%), food intolerance (14.9%) and premature termination (7.1%). A servo-controlled device (15.5%) or PCM (84.5%) was used, with comparable adverse events. 84.5% of the neonates were discharged, 7.1% discharged against medical advice and 8.4% died. Detailed neurological assessment at discharge/discharge against medical advice suggested neurological impairment in 128 (87.1%) neonates. Conclusion Adverse events during TH range from asymptomatic laboratory abnormalities to life-threatening complications, which are manageable in well equipped units. Neurological impairment at discharge in neonates who received cooling mandates strict neurological follow-up. Abbreviations: aEEG: amplitude-integrated EEG; AKI: acute kidney injury; BW: birthweight; EEG: electro-encephalogram; GA: gestational age; HELIX: hypothermia for encephalopathy in low- and middle-income countries; HIE: hypoxic ischaemic encephalopathy; IVH: intraventricular haemorrhage; LMIC: low- and middle-income countries; NICHD: National Institute of Child Health and Human Development; NICU: neonatal intensive care unit; PPHN: persistent pulmonary hypertension of newborn; PCM: phase-changing material; SGA: small-for-gestational age; TH: therapeutic hypothermia.