Background Surgical care holds significant fi cant importance in healthcare, especially in low and middle-income countries, as at least 50% of the 4.2 million deaths within the initial 30 days following surgery take place in these countries. The Lancet Commission on Global Surgery proposed six indicators to enhance surgical care. In Colombia, studies have been made using secondary data. However, strategies to reduce perioperative mortality have not been implemented. This study aims to describe the fourth indicator, perioperative mortality rate (POMR), with primary data in Colombia. Methods A multicentre prospective cohort study was conducted across 54 centres (hospitals) in Colombia. Each centre selected a 7-day recruitment period between 05/2022 and 01/2023. Inclusion criteria involved patients over 18 years of age undergoing surgical procedures in operating rooms. Data quality was ensured through a verification fi cation guideline and statistical analysis using mixed-effects multilevel modelling with a case mix analysis of mortality by procedure- related, patient-related, and hospital-related conditions. Findings 3807 patients were included with a median age of 48 (IQR 32-64), - 64), 80.3% were classified fi ed as ASA I or II, and 27% of the procedures had a low-surgical complexity. Leading procedures were Orthopedics (19.2%) and Gynaecology/Obstetrics (17.7%). According to the Clavien-Dindo - Dindo scale, postoperative complications were distributed in major complications (11.7%, 10.68-12.76) - 12.76) and any complication (31.6%, 30.09-33.07). - 33.07). POMR stood at 1.9% (1.48-2.37), - 2.37), with elective and emergency surgery mortalities at 0.7% (0.40-1.23) - 1.23) and 3% (2.3-3.89) - 3.89) respectively. Interpretation The POMR was higher than the ratio reported in previous national studies, even when patients had a low-risk - risk profile fi le and low-complexity procedures. The present research represents significant fi cant public health progress with valuable insights for national decision-makers to improve the quality of surgical care. 2024;38: 100862 Published Online https://doi.org/10. 1016/j.lana.2024. 100862