[Cardiac arrest during anesthesia at a tertiary teaching hospital: prospective survey from 1996 to 2002.]

Cardiac arrest (CA) incidence and causes during anesthesia are variable and difficult to be compared due design variations of major studies. This survey aimed at evaluating all intra and postoperative CA from 1996 to 2002 at a tertiary teaching hospital to determine CA incidence and causes.

The prospective incidence of CA during 40,941 anesthesias was identified from a database. All CA and deaths were reviewed by a Committee in order to determine triggering factors. CA cases were studied as to age, gender, ASA physical status, type of treatment, triggering factors, such as changes in patients physical status and surgical and anesthetic complications, type of anesthesia and evolution to death.

There were 138 CA (33.7:10,000), being most of them neonates, children aged less than 1 year, elderly people, males (65.2%), physical status ASA III or poorer, in emergency surgeries and during general anesthesia. Physical status changes were the major CA factor (23.9:10,000) followed by surgical complications alone (4.64:10,000) or associated to physical status changes (2.44:10,000) and anesthetic complications alone (1.71:10,000) or associated to physical status changes (0.98:10,000). The risk of anesthesia-related death as major or contributing factor was similar for both (0.49:10,000). Major anesthesia-related death causes were ventilatory problems (45.4%), drug-related events (27.3%), pulmonary aspiration (18.2%) and fluid overload (9.1%).

CA incidence during anesthesia is still high. Most anesthesia-related cardiac arrests and deaths were related to airway management and drug and anesthetic administration.