Utility of Routine Preoperative Laboratory Testing for Low-Risk Patients in Ambulatory Gynecologic Surgery

Abstract

Study Objective To evaluate the utility of routine preoperative laboratory testing in low-risk patients undergoing ambulatory gynecologic surgery. Design The American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database was queried for low-risk patients who underwent elective, ambulatory gynecologic surgery from 2015-2018. Setting The ACS NSQIP database is a validated, risk-adjusted surgical outcomes database that prospectively collects data from participating institutions nationally. Patients or Participants Low-risk patients selected for inclusion in this study were defined as being American Society of Anesthesiologists (ASA) class 1 or 2. This included 19,885 patients. Interventions Patient characteristics, comorbidities, and NSQIP-defined complications were compared between those with and without preoperative laboratory testing. Preoperative laboratory testing was defined as chemistry, hematology, coagulation, or liver function studies obtained within 30 days preoperatively. Measurements and Main Results Of 19,885 patients studied, 14,258 (71.8%) received preoperative laboratory testing, with at least one abnormal test identified in 4,053 (28.4%) patients. There was no statistically significant difference in overall postoperative complication rate when comparing patients who received preoperative laboratory testing with those who did not (2.5% vs. 2.2%, p=0.30). Additionally, there was no statistically significant difference in wound complications (1.0% vs. 1.0% p=0.78), major complications (1.0% vs. 0.8% p=0.11), unplanned return to the operating room (0.1% vs. 0.2%, p=0.40), unplanned readmission (0.7% vs. 0.5% p=0.10), or overall morbidity (2.1% vs. 1.9% p=0.38). Chi-squared analyses were performed to compare categorical variables. Continuous variables were compared using unpaired t-tests. Conclusion Preoperative laboratory testing continues to be performed in the majority of low-risk patients undergoing ambulatory gynecologic surgery despite evidence and guidelines that do not recommend this practice. However, there was no difference in surgical outcomes between patients who did and did not receive preoperative laboratory testing. Postoperative complications are infrequent in this patient population. These results suggest that preoperative laboratory testing should be used more judiciously in low-risk patients undergoing ambulatory gynecologic surgery. To evaluate the utility of routine preoperative laboratory testing in low-risk patients undergoing ambulatory gynecologic surgery. The American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database was queried for low-risk patients who underwent elective, ambulatory gynecologic surgery from 2015-2018. The ACS NSQIP database is a validated, risk-adjusted surgical outcomes database that prospectively collects data from participating institutions nationally. Low-risk patients selected for inclusion in this study were defined as being American Society of Anesthesiologists (ASA) class 1 or 2. This included 19,885 patients. Patient characteristics, comorbidities, and NSQIP-defined complications were compared between those with and without preoperative laboratory testing. Preoperative laboratory testing was defined as chemistry, hematology, coagulation, or liver function studies obtained within 30 days preoperatively. Of 19,885 patients studied, 14,258 (71.8%) received preoperative laboratory testing, with at least one abnormal test identified in 4,053 (28.4%) patients. There was no statistically significant difference in overall postoperative complication rate when comparing patients who received preoperative laboratory testing with those who did not (2.5% vs. 2.2%, p=0.30). Additionally, there was no statistically significant difference in wound complications (1.0% vs. 1.0% p=0.78), major complications (1.0% vs. 0.8% p=0.11), unplanned return to the operating room (0.1% vs. 0.2%, p=0.40), unplanned readmission (0.7% vs. 0.5% p=0.10), or overall morbidity (2.1% vs. 1.9% p=0.38). Chi-squared analyses were performed to compare categorical variables. Continuous variables were compared using unpaired t-tests. Preoperative laboratory testing continues to be performed in the majority of low-risk patients undergoing ambulatory gynecologic surgery despite evidence and guidelines that do not recommend this practice. However, there was no difference in surgical outcomes between patients who did and did not receive preoperative laboratory testing. Postoperative complications are infrequent in this patient population. These results suggest that preoperative laboratory testing should be used more judiciously in low-risk patients undergoing ambulatory gynecologic surgery.