Serum lactate predicts resource utilization, but not surgical need, in the emergency department.

BACKGROUND: Serum lactate is frequently tested in the emergency department (ED) setting to diagnose visceral ischemia and as a marker of end-organ perfusion. It is highly nonspecific, and levels can be affected by both kidney and liver function. In this retrospective chart review, we aim to demonstrate that serum lactate is overused in the ED setting and predicts resource utilization but not the need for surgical intervention.

METHODS: ED records with a chief complaint of "abdominal pain" were queried for the preceding 12 mo. We excluded pregnant patients, patients aged less than 18 years, and patients for whom a blood count and chemistry were not obtained. Vital signs, laboratory values, resource utilization, and outcome of the visit were obtained. Logistic regression models were developed to correct for confounding associations.

RESULTS: A total of 1003 records were obtained initially with 753 patients (75%) included in the study. Serum lactate was drawn in 118 patients (15%) and was elevated in 19 patients (16% of those drawn). Utilization of computed tomography imaging was associated with lactate utilization (P < 0.001). Patients in whom lactate was drawn were more likely to have a general surgery consult (51% versus 34%, P < 0.001) and to be admitted to the hospital (P < 0.001).

CONCLUSIONS: The use of serum lactate in the workup of patients with abdominal pain should be targeted at patients who have signs of sepsis and based on the index of suspicion for specific disease processes such as mesenteric ischemia.