Documented perioperative adverse events in paediatric anaesthesia in Mongolia: a first national baseline report.

Background: Paediatric anaesthesia safety depends on reliable data regarding perioperative adverse events. However, many low- and middle-income countries lack integrated reporting systems, making it difficult to estimate risk, identify modifiable factors, or monitor safety improvement. Mongolia has developed paediatric anaesthesia services through national training and international collaboration; however, no national system currently exists for systematic reporting of paediatric anaesthesia-related adverse events. This study aimed to provide the first national baseline description of documented perioperative adverse events in paediatric anaesthesia in Mongolia. Methods: We conducted a multicentre retrospective chart review at the main tertiary paediatric hospital and five provincial hospitals providing paediatric surgical services in Mongolia. All paediatric anaesthetic procedures performed between 1 January 2018 and 31 December 2022 were eligible. Anaesthesia charts, recovery room records, intensive care records, and other relevant perioperative documents were manually reviewed. Documented adverse events were classified as cardiovascular, respiratory, neurological, or other perioperative events. Results were summarized descriptively at the record and event levels. Results: Across 60,546 paediatric anaesthetic procedures, 640 records contained documentation of at least one perioperative adverse event. After exclusion of three records with insufficient documentation, 637 records were included in the final analysis. These records included a total of 1,159 documented perioperative adverse events, corresponding to 19.1 documented events per 1,000 procedures. Cardiovascular events were the most frequently documented category ( Conclusions: This study provides the first national baseline report on documented perioperative adverse events in paediatric anaesthesia in Mongolia. Cardiovascular and respiratory events were the most frequently documented categories, while serious adverse events were uncommon. Because this study relied on retrospective review of routine clinical records, the findings should be interpreted as documented event rates rather than definitive estimates of true incidence. These baseline data support the development of a prospective national reporting system, standardized event definitions, targeted training, and system-level safety improvements in Mongolian paediatric anaesthesia.