Comparative Evaluation of Perfusion Index With Lactate and Base Deficit for Assessing Resuscitation Response in Traumatic Shock Patients Not Requiring Blood Transfusion in the Emergency Department.

Introduction  Traumatic shock is a life-threatening condition characterized by inadequate tissue perfusion following severe injury. Early recognition of impaired perfusion and monitoring of the response to resuscitation are essential to prevent organ dysfunction. Although lactate and base deficit are commonly used biochemical markers of tissue hypoperfusion, their measurement requires invasive blood sampling. The perfusion index provides a continuous, non-invasive assessment of peripheral perfusion. This study aimed to compare the perfusion index with lactate and base deficit as indicators of resuscitation response in traumatic shock patients who did not require blood transfusion in the emergency department. Methodology A cross-sectional observational study was conducted from March 2025 to February 2026 involving adult patients with traumatic hemorrhagic shock (Class I-III). A total of 55 patients (n=55) meeting the inclusion and exclusion criteria were recruited through convenience sampling. The perfusion index was measured using a pulse oximeter, and arterial blood gas analysis was performed to assess lactate levels and base deficit at baseline, one hour, and two hours after the initiation of resuscitation. Data were analyzed to evaluate the relationship between the perfusion index and biochemical markers in assessing the response to resuscitation using correlation analysis, kappa statistics, receiver operating characteristic (ROC) curve analysis, and multivariable logistic regression. Results Among 55 patients, the perfusion index (PI) showed a progressive increase during resuscitation, while lactate and base deficit declined significantly. PI increased by +0.67 units per hour, and lactate decreased by -2.28 mmol/L per hour (