[Value of preoperative screening studies]

In order to develop a sensitive and economically reasonable preoperative screening program capable of identifying perioperative risk factors, we performed a prospective study on patients scheduled for elective urological surgery. According to age, 379 patients were assigned to six groups. After the history and physical examination had been completed the attending anesthesiologist classified the patient's anesthetic risk according to ASA criteria. Furthermore, based on his clinical impression he ordered an individual set of screening parameters (laboratory tests, X-ray films, electrocardiography (ECG), and other appropriate diagnostic procedures) to be done. This "individual" screening and its results were compared with the results of the larger "routine" preoperative screening program performed independently of the study for all patients. All cases were then followed up in order to document perioperative complications. We were thus, able to recognize risk-identifying screening parameters resp. pathological findings missed by the "individual" screening. Laboratory tests from the nonselective "routine" screening yielded pathological results in a relatively high percentage of 31.4% of cases. ECG alterations or chest X-ray findings relevant to the patient's anesthetic management were present in 26.1% resp. 13.6%. Observations missed by the "individual" screening, though important for the prevention of perioperative complications, were pathological ECGs in only 1.9% of all cases. An influence of patient age on the frequency of pathological screening results and perioperative complications could be shown. Laboratory tests, chest X-rays and additional diagnostic procedures should be restricted to patients with pathological results or physiological examination. Our results underline once more the importance of a carefully taken history, a meticulous physical examination and the preoperative performance of an ECG for patients of every age scheduled for anesthesia and surgery.