Lactic Acid Levels Are Associated with Morbidity, Length of Stay, and Total Treatment Costs in Urban Trauma Patients with Lower Extremity Long Bone Fractures

Lactic acid is well studied in the trauma population and is frequently used as a laboratory indicator that correlates with resuscitation status and has thus been associated with patient outcomes. There is limited literature that assesses the association of initial lactic acid with post-operative morbidity and hospitalization costs in the orthopedic literature. The purpose of this study was to assess the association of lactic acid levels and alcohol levels post-operative morbidity, length of stay and admission costs in a cohort of operative lower extremity long bone fractures, and to compare these effects in the ballistic and blunt trauma sub-population. Patients presenting as trauma activations who underwent tibial and/or femoral fixation at a single institution from May 2018 to August 2020 were divided based on initial lactate level into normal, (< 2.5) intermediate (2.5–4.0), and high (> 4.0). Mechanism of trauma (blunt vs. ballistic) was also stratified for analysis. Data on other injuries, surgical timing, level of care, direct hospitalization costs, length of stay, and discharge disposition were collected from the electronic medical record. The primary outcome assessed was post-operative morbidity defined as in-hospital mortality or unanticipated escalation of care. Secondary outcomes included hospital costs, lengths of stay, and discharge disposition. Data were analyzed using ANOVA and multivariate regression. A total of 401 patients met inclusions criteria. Average age was 34.1 ± 13.0 years old, with patients remaining hospitalized for 8.8 ± 9.5 days, and 35.2