A prospective study of risk factors and cardiopulmonary complications associated with anaesthesia and surgery: risk indicators of cardiopulmonary morbidity.

The aims of this study were: 1) to describe the frequency and type of cardiopulmonary complications, 2) to identify factors significantly associated with cardiovascular and pulmonary complications associated with anaesthesia and surgery, and 3) to estimate the total risk of cardiopulmonary complications for an anaesthetic when a combination of risk factors is present. Seven thousand three hundred and six anaesthetized patients undergoing gastrointestinal, urological, gynaecological, and orthopaedic surgery were included in the study; 6.3% (1:16) had one or more cardiovascular complications requiring intervention associated with anaesthesia and surgery, and 4.8% (1:21) had pulmonary complications. The total incidence of patients with one or more complications associated with anaesthesia and surgery was 9.4% (1:11). Based on logistic regression analyses, our data indicate that the following patient categories constitute high risk patients with regard to cardiovascular complications: patients aged greater than or equal to 70 years, patients with a history of ischaemic heart disease (IHD) with previous myocardial infarction less than 1 year, a history of chronic heart failure (CHF), and in patients admitted to major surgery. The extent of pulmonary complications following anaesthesia and surgery was significantly correlated to patients aged greater than or equal to 70 years, preoperative chronic obstructive lung disease (COLD), major surgery, and to general anaesthesia involving muscle relaxants. Attempts to estimate the cardiopulmonary complications which may accompany anaesthesia and surgery provided important information about the anaesthetic course and outcome. With our model it seems possible to distinguish between very different levels of cardiopulmonary risk in the anaesthetic patient.