Background Apnoea is a common respiratory complication in preterm neonates, leading to substantial changes in physiology. We conducted this systematic review and meta-analysis to examine the relationship between apnoea duration and changes in physiology in preterm neonates, and to identify factors that modulate this relationship.

Methods We searched Medline, EMBASE, PsycINFO, and Cochrane Central Register of Controlled Trials databases and included primary empirical studies examining the relationship between apnoea or respiratory pause duration and at least one outcome (heart rate, blood oxygen saturation, cerebral oxygenation, cerebral blood volume) in hospitalised neonates with postmenstrual age (PMA) <37 weeks. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal checklist. Results were synthesised narratively and quantitative data was pooled for meta-analysis.

Results Forty-two papers were included, involving a total of 1,483 neonates with 2,399 study sessions. The decrease in heart rate, oxygen saturation, and cerebral oxygenation were significantly correlated with apnoea duration. PMA significantly modulated the relationship, with younger neonates more likely to exhibit oxygen desaturation from short apnoeas.

Conclusions These findings indicate that shorter apnoea alarm thresholds should be considered for younger infants.

Impact statement:

What is the key message of your article?

What does it add to the existing literature?

Through meta-analysis, we demonstrate that postmenstrual age plays a significant modulating role in the relationship between apnoea duration and change in oxygen saturation, with younger infants more likely to have significant desaturations.

The authors have declared no competing interest.

This work was funded by the Wellcome Trust and Royal Society through a Fellowship provided to CH (grant reference number: 213486/Z/18/Z). YC is funded by the Department of Paediatrics at the University of Oxford and the China Scholarship Council (CSC).

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All extracted data are provided in Supplementary Table 1.