Perioperative mortality related to anesthesia within 48 h and up to 30 days following surgery: A retrospective cohort study of 11,562 anesthetic procedures.

•Perioperative mortality is associated with the patient's condition, the surgical procedure and the anesthetic act.•The majority of perioperative deaths up to 30 days were considered inevitable (50.7%), as they were related to advanced illnesses.•Deaths with connection to the anesthesia were of early occurrence (less than 48 hours after surgery).•Transoperative vasopressor, extremes of age and out-of-hour surgery were independent variables associated to early deaths.