Perioperative cardiac arrests - A subanalysis of the anesthesia -related cardiac arrests and associated mortality

Study objective: To determine the incidence, risk factors, and predictors of survival of perioperative cardiac arrests (PCAs) occurring in patients who underwent non-cardiac and non-obstetric surgery from January 2008 to May 2015 at a tertiary hospital; determine the incidence and risk factors of anesthesia-related PCA.

Design: Retrospective observational study.

Setting: Operating room and postoperative recovery area.

Patients: Sixty-two PCA cases from an anesthesia database of 122,289 anesthetics.

Interventions: Each PCA was classified as anesthesia-related, partially anesthesia-related, or anesthesia unrelated. The main outcome variables were occurrence of PCA, survival at least 1 h after initial resuscitation and survival to hospital discharge. To determine the risk factors for PCA, for each patient who suffered a PCA, two other patients that underwent anesthesia on the same day and in the same operating suite were selected.

Measurements: Three sets of variables were collected; patient-related, surgical procedure-related, and PCA-related.

Main results: The incidence of PCAs of all causes was 5.07 per 10,000 anesthetics, and the associated mortality was 2.9 per 10,000 anesthetics. The independent risk factors for occurrence were: ASA PS score higher than 3, diagnosed cardiac disease, and the use of vasopressors. Decreased survival was associated with: higher ASA PS score, urgent surgical procedures of a higher complexity, use of vasopressors, documented hypotension prior to PCA, and arrests due to bleeding. The incidence of anesthesia-related PCAs was 0.74 per 10,000 anesthetics, and the associated mortality was 0.08 per 10,000 anesthetics. The main causes of anesthesia-related PCAs were associated with medication and airway/ventilation, and the independent risk factors for occurrence were: ASA PS score higher than 3 and diagnosed cardiac disease.

Conclusions: Most PCAs were not due to anesthesia-related causes, and anesthesia-related PCAs were associated with improved survival. Improvements in the management of high-risk patients, medication administration, and airway/ventilation management may result in better outcomes.