Efficiency of Respiratory Index in Determining Short-Term Prognosis of Multiple Trauma Patients: A Cross-Sectional Study


1 Assistant Professor of Anesthesiology and Critical Care, Trauma Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

2 Trauma Research Center, Shahid Rajaee (Emtiaz) Trauma Hospital, Shiraz University of Medical Sciences, Shiraz, Iran

3 Resident of Ophthalmology, Shiraz University of Medical Sciences, Shiraz, Iran



Being aware of trauma patients’ conditions and predicting their outcome has always been of a great interest. To determine the state and prognosis of these patients, we should find ways to enable the timely identification of those with poor health and allow the physicians to treat them before the situation gets out of hand.

The present study aimed at evaluating the efficiency of respiratory index (RI) in determining the short-term prognosis of multiple trauma patients in comparison with revised trauma score (RTS).

In this cross-sectional study, all multiple trauma patients who were admitted to emergency department (ED) of Shahid Rajaee hospital, Shiraz, Iran, during September and October 2013 were included. Demographic data and data regarding vital signs (blood pressure, heart rate, respiratory rate, GCS, and oxygen saturation), respiratory tract status, trauma type, blood gases, procedures performed in resuscitation room, and final outcome of the patients (discharge, disposition to general unit, intensive care unit, or operating room, and dying) were recorded using a predesigned checklist. Based on the collected data, RTS and RI were calculated for each patient and their correlation and the final outcome were evaluated.

Evaluating 187 multiple trauma patients showed that 131 (70%) patients had head injury, 78 (42%) chest injury, 66 (35%) abdominal injury, 49 (26%) extremity injury, 27 (14%) neck injury, and 4 (2%) vascular injury. A significant correlation was seen between RI and RTS (P = 0.024). RTS differentiated patients with good and poor health (P < 0.05), while RI showed no significant correlation with patients’ short-term final outcome.

Based on the findings of this study, RI cannot properly estimate short-term prognosis of multiple trauma patients, but it can be used as an independent factor in evaluating the severity of injury.


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