The effect of acute respiratory events and respiratory stimulants on EEG-recorded brain activity in neonates: A systematic review

Objective: We conducted a systematic review to investigate electroencephalography (EEG) changes during periods of acute respiratory events such as apnoea and the effect of respiratory stimulants on EEG features in infants. Methods: Studies examining respiration and EEG-recorded brain activity in human neonates between 28 and 42 weeks postmenstrual age were included. Two reviewers independently screened all records and included studies were assessed using the Joanna Briggs Institute Critical Appraisal Tool. The protocol was registered in PROSPERO (CRD42022339873). Results: We identified 14 studies with a total of 534 infants. Nine articles assessed EEG changes in relation to apnoea, one assessed hiccups, and four investigated the effect of respiratory stimulants. The relationship between neonatal apnoea and EEG changes was inconsistent; EEG suppression and decreased amplitude and frequency were observed during some, but not all, apnoeas. Respiratory stimulants increased EEG continuity compared with before use. Conclusions: Current studies in this area are constrained by small sample sizes. Diverse exposure definitions and outcome measures impact inference. Significance: This review highlights the need for further work; understanding the relationship between respiration and the developing brain is key to mitigating the long-term effects of apnoea