Cost benefit analysis of same day pregnancy tests in elective orthopaedic surgery

Abstract

We reviewed the results of 4,723 day of surgery pregnancy tests performed at two of our institution's locations, our ambulatory surgery center and our acute orthopaedics hospital over a 23 month time period. All patients were scheduled for elective orthopaedic surgery. There were seven positive results (0.15%) and one false negative result (0.02%). The cost per positive result for both hospital locations was $1,005.32.

Introduction: Performing elective surgery on pregnant women can harm the mother and fetus. In order to minimize the likelihood of this happening, we administer a urine pregnancy test to each woman of childbearing age on the date of surgery. From November 2009 to September 2011, we performed 4,723 urine human chorionic gonadotropin (hCG) pregnancy tests on the day of surgery. We reviewed the results and cost of each pregnancy test. We then used these results to calculate the percentage of positive tests and the cost of diagnosing each pregnant female on the date of their surgery.

Methods: We obtained the records of all urine hCG pregnancy tests performed from November 2009 to September 2011. Each test was reviewed to determine if the result was positive or negative. Costs were calculated using the charges incurred for a qualitative hCG pregnancy test. We then contacted each patient with a positive result to determine if the urine hCG test results were accurate.

Results: 4,723 pregnancy tests were reviewed over a 23 month period with 7 (0.15%) having a positive result. Over the 23 month time period, we were notified of one false negative result (0.02%). The Positive Predictive Value (PPV) was 100% and the Negative Predictive Value (NPV) was 99.9%. The cost of a single urine hCG test was $1.49, the total cost for all 4,723 tests was $7,037.27. The cost of diagnosing 7 positive tests was $1,005.32.

Conclusion: Routinely performing urine hCG pregnancy tests on the day of surgery is a cost effective method of preventing elective orthopaedic surgery on pregnant women. Of 4,723 women tested 7 had a positive result and 1 had a false negative result. The cost of $1,005.32 for each positive test must be compared with the benefit of not performing elective surgery on a pregnant female.