Usefulness of routine preoperative testing: a prospective single-observer study

The purpose of this study is to determine whether routine preoperative testing has a usefulness not previously recognized in a small preliminary study to decide if such a hypothesis might be worthy of testing in a larger study.

Single-observer, prospective, observational study.

Tertiary-care referral center in South India that performs 11 preoperative tests on each patient.

One hundred twenty-seven adult patients scheduled for elective neurosurgery.

Patients were studied to determine whether outcome was influenced by laboratory tests, which were either indicated by health history elicited by a computerized rule-based questionnaire or unindicated by patient history.

Of the 1395 tests performed preoperatively, 513 (36.8%) were indicated and 882 (63.3%) were unindicated. Of 513 indicated tests, 17 (3.3%) prompted changes in patient care; 8 (0.91%) of 882 unindicated tests (P < .001) prompted changes in care. All patients with anemia, significant electrocardiographic abnormalities, or HIV infection were detected by the computerized questionnaire. Among the changes in care prompted by unindicated tests, 4 patients received diabetic therapy or counseling, and 4 patients with abnormal silhouettes on chest radiograph had nonbeneficial echocardiography. Only screening for diabetes seemed to have usefulness as a routine preoperative test in this patient population.

Although the incidence of unindicated preoperative screening tests is still more than 50%, no previously unidentified benefit was found to support this persistence of unwarranted testing. The limited number of patients in this study necessitates a larger study to ensure greater certainty before such a recommendation is made to the public. If similar results in another but larger study involving similar design, simple changes in the system of preoperative care may save the health care system the considerable expense of unwarranted testing.