Traditionally, preoperative evaluation has included a variety of laboratory and screening tests intended to detect previously undetected conditions. Although these tests should be based on results of a history and physical examination, they are often ordered based simply on the requirements of the facility where the surgery will be performed. Tests generally include a complete blood count (CBC), chemistry profile, prothrombin time, partial thromboplastin time, urinalysis, electrocardiogram (ECG) and chest radiograph. However, the yield (in terms of abnormal test results that would change the management of a surgical candidate) of such tests is quite low. Many facilities are now changing their preoperative requirements. Mancuso compared preoperative testing patterns before and after guidelines were issued at an orthopedic hospital.

The old preoperative guidelines called for the above-mentioned tests as well as erythrocyte sedimentation rate and reactive plasmin reagin. The new guidelines called only for a CBC in all patients plus an ECG in patients 50 years of age or older. Physicians were free to order any additional tests deemed necessary. The type of anesthesia used in the surgery was recorded, as was the site of surgery (categorized as foot/ankle, hip/knee, hand/wrist and shoulder/sports surgery). Follow-up telephone calls were made to patients to screen for postoperative complications.

The authors studied the records of 640 patients who underwent surgery during a four-year period—from two years before to two years after the new guidelines were issued. At least eight preoperative tests were ordered in 80 percent of patients before the change in guidelines, compared with 48 percent of patients after the change. Overall, the number of tests ordered after guideline implementation decreased by 30 percent.

Patients with more comorbidities had less of a decrease in the number of tests ordered. The testing guidelines were strictly followed in only 15 percent of patients. The most common addition to the testing guidelines in patients under 50 years of age was an ECG. Rates of postoperative hospital admission did not vary before and after the guidelines, and 94 percent of patients had no intraoperative or postoperative complications of any sort. The cost savings in the two years after the guidelines were implemented was over $650,000 for ambulatory orthopedic surgery patients.

The author concludes that preoperative testing guidelines can fairly easily decrease costs without increasing the patient's medical risks and complications. Expert panel recommendations and guidelines that address specific clinical situations when preoperative testing is considered could further reduce costs.