E. D. Porter1, J. L. Kelly1, A. R. Wilcox1, S. W. Trooboff1, J. D. Phillips1, C. V. Angeles1 1Dartmouth Hitchcock Medical Center,Surgery,Lebanon, NH, USA
Introduction: Overutilization of laboratory testing in hospitalized patients continues to challenge cost-effective care. Prior efforts to reduce unnecessary lab testing in the surgical population have been limited to preoperative testing and critical care patients. We sought to investigate our institution’s post-operative lab (POL) ordering practice on adult elective general surgery patients and its impact on clinical decision-making and outcomes.
Methods: Retrospective cohort study at a single academic center. All adult elective general surgery patients with a <48 hour admission from April-June 2018 were selected. Patients with a condition requiring lab testing (e.g. on coumadin) were excluded. We reviewed patient charts for demographics, comorbidities, POL orders, documentation of POL abnormalities, and 30-day complications. We compared patients receiving or not receiving POLs using student’s t-test, chi-square and one-way analysis of variance for continuous, dichotomous, and categorical covariates, respectively. Significance was set at p<0.05.
Results: In our study period, 171 patients were admitted for <48 hours after elective general surgery. Surgical procedures were classified as intestinal (n=116), solid abdominal organ (n=9), hernia (n=9), thoracic (n=22), breast (n=11), and other (n=4). Routine POLs were ordered on 89% of patients (153/171), with significant differences in frequency of ordering labs by surgery type (Figure 1). On univariate analysis, patients who did not have POLs had significantly lower BMI (p<0.004); there was no difference in age, demographics, comorbidities, blood loss, or ASA status. Of those who had POLs, 88% had an abnormality (134/153), and the abnormality was commented on in 20% of progress notes (27/134). A POL only changed care in 12% of patients (19/153). Change in care included electrolyte correction (15/19), medication held (2/19), additional test (1/19), and fluid resuscitation (1/19). White blood cell count and/or hemoglobin levels were abnormal in 84% (128/153); however, none of these abnormalities prompted a change in care. Electrolytes were abnormal in 14% of cases (21/153) and led to a change in care for 76% (16/21). Creatinine was elevated in 3% (5/153) and led to a change in care for 80% (4/5). There was no significant difference in 30-day complication or readmission rates for those who received POLs.
Conclusion: POL testing is common among adult elective general surgery patients who have brief hospitalizations. While most labs yielded abnormal results in our cohort, these were unlikely to be commented on and even less likely to change care. Routine POL testing without clinical indication is overutilized and interventions to reduce this practice are needed.
