The following is a summary of “Prehospital Lactate Levels Obtained in the Ambulance and Prediction of 2-Day In-Hospital Mortality in Patients With Traumatic Brain Injury,” published in the August 2024 issue of Neurology by Martin-Rodriguez, et al.

Researchers retrospectively analyzed prehospital lactate levels to predict 2-day and 90-day in-hospital mortality in patients with traumatic brain injury (TBI), stratified by severe TBI (Glasgow Coma Scale (GCS) ≤ 8) and mild/moderate TBI (GCS ≥ 9).

They conducted multicenter, emergency medical services (EMSs) delivery, ambulance-based derivation-validation cohort study across 5 tertiary hospitals (Spain) (November 1, 2019, to July 31, 2022). Patients were recruited from emergency phone requests among adults and later transported to referral hospitals with acute TBI. Minors, pregnant individuals, trauma patients without TBI, delayed presentations, those discharged on-site, patients with cardiac arrest, and those unable to provide a blood sample were excluded. The study compared 2-day and 90-day mortality between patients with mild/moderate and severe TBI, analyzing lactate and glucose levels and assessing the AUC and calibration curve in two cohorts.

The results showed 509 patients with a median age of 58 (IQR: 43–75). Among, 167 patients were female (32.8%). The primary outcome was observed in 9 (2.2%) of 415 patients with moderate or mild TBI and 42 (44.7%) of 94 patients with severe TBI. The lactate concentration’s predictive capacity was validated with an area under the receiver operating characteristic curve (AUC) of 0.874 (95% CI 0.805–0.942) for the validation cohort. The GCS score’s ability to predict lactate concentration was higher in patients with a GCS score ≥9 points, showing an AUC of 0.925 (95% CI 0.808–1.000) and a negative predictive value of 99.09% (95% CI 98.55–99.64) in the validation cohort.

Investigators concluded that prehospital lactate levels were beneficial in predicting mortality in patients with TBI, especially with GCS ≥ 9, suggesting the potential for reduced mortality and deterioration rates through patients at risk with early identification.

Source: neurology.org/doi/10.1212/WNL.0000000000209692