OUTCOMES OF PATIENTS WITH NO LABORATORY ASSESSMENT BEFORE ANESTHESIA AND A SURGICAL-PROCEDURE

Objective: To estimate the frequency of perioperative morbidities in p atients who underwent anesthesia and a surgical procedure with no preo perative laboratory testing. Material and Methods: We conducted an ele ctronic database search of medical records of 56,119 patients who unde rwent surgical or diagnostic procedures and anesthesia at Mayo Clinic Rochester in 1994 and found 5,120 who had no laboratory tests done wit hin 90 days before the procedure. From this group, we randomly selecte d 1,044 patients (87 from each month) to document the absence of preop erative tests, the presence of preexisting disease (by organ system), the type of anesthetic agent, and the outcomes and tests intraoperativ ely and postoperatively. Results: The 1,044 patients ranged in age fro m 0 to 95 years (median age, 21). No deaths or major perioperative mor bidities occurred (0.0%; exact 95% confidence interval, 0.00 to 0.35%) . Although 10 patients underwent blood typing and screening for antibo dies immediately preoperatively, no blood transfusions were necessary. Intraoperatively, 17 laboratory tests and 1 electrocardiogram were ob tained, and 3 results were abnormal. Postoperatively, 42 blood tests a nd 2 electrocardiographic procedures were performed. Five of the 42 bl ood tests showed abnormal results (hemoglobin levels in 3, serum sodiu m in 1, and arterial blood gases in 1). One electrocardiogram showed n ormal findings, and the other revealed normal results except for prema ture ventricular contractions. No laboratory test done intraoperativel y or postoperatively was found to change surgical or medical managemen t substantially. One patient who had unanticipated blood loss during a n outpatient procedure was admitted to the hospital for observation. C onclusion: All 1,044 patients, 97% of whom were relatively healthy, wi th no recent laboratory testing safely underwent anesthesia and an ope ration. We conclude that patients who have been assessed by history an d physical examination and determined to have no preoperative indicati on for laboratory tests can safely undergo anesthesia and operation wi th tests obtained only as indicated intraoperatively and postoperative ly. Current anesthetic and medical practices rapidly identify perioper ative indications for laboratory evaluation as they arise.