Revised Trauma Score
The Revised Trauma Score (RTS) is a standardized physiological scoring system designed to evaluate the severity of injuries in trauma patients by quantifying three key clinical parameters: the Glasgow Coma Scale (GCS) for neurological status, systolic blood pressure (SBP) for circulatory function, and respiratory rate (RR) for ventilatory effort.[1] Developed as a refinement of the original Trauma Score introduced in 1981, the RTS was first published in 1989 by Champion et al. to simplify field assessment, eliminate subjective elements like capillary refill and respiratory expansion that were prone to interobserver variability, and improve prognostic accuracy, particularly for head injuries.[2] The score ranges from 0 (indicating severe physiological derangement and high mortality risk) to 12 (normal vital signs and low risk), with a triage version (T-RTS) using raw coded values for rapid prehospital decision-making and a weighted coded version (coded RTS or RTSc) calculated as RTSc = 0.9368 × GCSc + 0.7326 × SBPc + 0.2908 × RRc for outcome prediction, where each component is coded from 0 (worst) to 4 (best).[3][1] In clinical practice, the RTS serves multiple critical roles, including prehospital triage to identify patients requiring immediate transport to trauma centers—typically those with an RTS below 11 or 12—and predicting in-hospital mortality, with studies showing high sensitivity (e.g., 97% at a cutoff of 7.108 for geriatric patients) and specificity (e.g., 80-90.5% in various cohorts).[2][3] It is particularly valuable in resource-limited settings and for helicopter emergency medical services evaluations, where a cutoff of 11.5 has demonstrated 84% sensitivity and 90.5% specificity for severe outcomes.[2] However, limitations include potential underestimation of isolated head injuries due to its reliance on vital signs, challenges in scoring intubated or sedated patients, and inferior performance compared to combined systems like TRISS (Trauma and Injury Severity Score) or KTS (Kampala Trauma Score) in some mortality predictions (e.g., KTS sensitivity of 0.88 vs. RTS 0.82).[2][3] Despite these, the RTS remains a cornerstone of trauma care, integrated into major databases like the National Trauma Data Bank for quality improvement and research.[3]Overview
Definition and Purpose
The Revised Trauma Score (RTS) is a physiological scoring system designed to quantify trauma severity by integrating assessments of three key vital signs: the Glasgow Coma Scale (GCS), systolic blood pressure (SBP), and respiratory rate (RR).[1] Developed as a refinement of earlier trauma assessment tools, the RTS provides a standardized, rapid method to evaluate a patient's physiological response to injury, enabling clinicians to gauge the extent of derangement in critical functions without requiring anatomical details.[2] This approach emphasizes functional impairment over injury location, making it particularly suitable for initial evaluations in resource-limited environments.[1] The primary purpose of the RTS is to facilitate quick triage decisions in prehospital and emergency department settings, predict survival probabilities, and inform resource allocation for trauma patients.[2] By offering a numerical representation of injury severity, it helps prioritize patients for transport to appropriate facilities, such as trauma centers, thereby optimizing outcomes and reducing unnecessary transfers.[1] The score's design supports both triage (using a simplified version) and prognostic applications, contributing to evidence-based protocols that minimize overtriage and undertriage errors.[2] The weighted coded RTS yields a score ranging from 0 (indicating the worst prognosis with no vital signs) to 7.8408 (representing normal physiological status and the best prognosis), while the triage version (T-RTS) ranges from 0 to 12.[1] Established in 1989 as an improvement over the original 1981 Trauma Score, the RTS enhances field applicability by simplifying components and improving reliability in low-light or chaotic conditions.[1]Key Components
The Revised Trauma Score (RTS) relies on three key physiological parameters to evaluate trauma severity: the Glasgow Coma Scale (GCS), systolic blood pressure (SBP), and respiratory rate (RR). These components provide a rapid assessment of neurological, circulatory, and ventilatory functions, respectively, enabling clinicians to gauge patient stability in resource-limited settings.[4] The Glasgow Coma Scale measures neurological function through evaluations of eye opening, verbal response, and motor response, with scores ranging from 3 (indicating severe coma and profound impairment) to 15 (fully alert), where scores of 13-15 indicate mild or no neurological deficit. This parameter is clinically significant for detecting traumatic brain injuries, which are a leading cause of mortality in trauma patients, as it quantifies level of consciousness and potential intracranial damage.[4][3] Systolic blood pressure assesses circulatory stability, with normal values exceeding 89 mmHg and critical lows approaching 0 mmHg (indicating no palpable pulse and severe hypovolemic or cardiogenic shock). It is vital for identifying hemorrhagic shock, a common complication in trauma that can lead to organ failure if not addressed promptly.[4][3] Respiratory rate evaluates ventilatory status, where normal ranges fall between 10 and 29 breaths per minute, while extremes such as greater than 29 breaths per minute (tachypnea signaling distress) or 0 (apnea indicating respiratory arrest) denote severe compromise. This component highlights issues like pneumothorax or aspiration, which impair oxygenation and contribute to rapid deterioration.[4][3] These parameters were selected for the RTS because they can be obtained quickly and reliably in prehospital or emergency environments without advanced equipment, imaging, or laboratory tests, while strongly correlating with mortality risk in trauma cases.[4] In multisystem trauma, derangements often interlink; for instance, low SBP from blood loss frequently coincides with elevated RR due to compensatory tachypnea and reduced GCS from hypoperfusion-induced cerebral hypoxia, amplifying overall prognostic concern.[3]History and Development
Original Trauma Score
The Original Trauma Score (TS), developed by Howard R. Champion and colleagues in the mid-1970s as an initial field triage tool for trauma patients, was formally published in 1981.[5] This system marked the first physiological scoring method designed specifically for prehospital assessment, drawing from Champion's experience in military trauma care to enable rapid evaluation of injury severity without relying solely on anatomical descriptions.[6] It aimed to standardize triage decisions by quantifying vital signs and neurological status, facilitating the transport of patients to appropriate facilities.[7] The TS comprised five unweighted parameters: the Glasgow Coma Scale (GCS) for neurological function, systolic blood pressure (SBP) for circulatory status, respiratory rate (RR) for ventilatory effort, respiratory expansion for chest mechanics, and capillary refill time for peripheral perfusion.[2] GCS, SBP, and RR were each scored from 0 (worst) to 4 (best), while respiratory expansion and capillary refill were scored from 0 to 2, yielding a total score ranging from 0 to 16, with higher values reflecting better overall physiological stability.[8] Scores of 12 or below were typically indicative of major trauma requiring transport to a trauma center.[9] Despite its innovation, the TS had notable limitations that hindered its practical application. The inclusion of five parameters made it somewhat complex for quick field calculation under time constraints, particularly in resource-limited prehospital environments.[2] Moreover, the capillary refill component proved subjective and unreliable, varying with observer experience and environmental factors such as temperature.[2] The unweighted summation also failed to adequately prioritize parameters for prognostic purposes, reducing its precision in predicting survival outcomes.[7] Early validation efforts, as reported in the foundational study, demonstrated a correlation between TS values and survival rates across civilian and military datasets.[5] Subsequent prehospital trials confirmed its utility for triage, with sensitivity around 90% for identifying severe injuries, though inter-rater variability remained a concern.[9] These findings established the TS as a foundational tool, prompting revisions to address its shortcomings.Creation of the Revised Trauma Score
The Revised Trauma Score (RTS) was developed by Howard R. Champion and colleagues to refine the original Trauma Score, enhancing its practicality for prehospital triage and more accurate mortality prediction in trauma patients. First published in 1989 in the Journal of Trauma, the RTS emerged from efforts to address inconsistencies in field assessments and improve prognostic reliability.[1] A primary rationale for the revision was to eliminate subjective components prone to interobserver variability, such as capillary refill time and respiratory expansion, which complicated rapid evaluation in austere environments. Instead, the RTS streamlined to three objective physiological parameters: the Glasgow Coma Scale (GCS) for neurological status, systolic blood pressure (SBP) for circulatory adequacy, and respiratory rate (RR) for ventilatory function. This reduction prioritized measurable vital signs while introducing a weighted summation formula, derived via logistic regression, to better correlate with survival outcomes and emphasize head injury impacts through heavier GCS weighting. The weights were calculated using data from the Major Trauma Outcome Study (MTOS), a large-scale retrospective analysis of over 80,000 trauma cases across 139 North American hospitals from 1982 to 1987, enabling robust statistical modeling of physiological derangements against mortality.[1][10][11] Initial validation confirmed the RTS's superiority over its predecessor, with the triage-oriented version (T-RTS) demonstrating over 97% sensitivity in identifying nonsurvivors who required trauma center transfer, albeit with a modest trade-off in specificity. For outcome prognostication, the full RTS exhibited enhanced reliability and predictive accuracy, particularly for head-injured patients, achieving an area under the receiver operating characteristic curve (AUC) of approximately 0.85 for mortality in foundational datasets. These improvements established the RTS as a more dependable physiologic index for trauma severity.[1] The RTS gained rapid acceptance following its introduction, with integration into the American College of Surgeons' Advanced Trauma Life Support (ATLS) guidelines in early subsequent editions, solidifying its role as a core component of standardized trauma care protocols.[2]Calculation Method
Parameter Coding
The Revised Trauma Score (RTS) employs a categorical coding system for its three physiological parameters—Glasgow Coma Scale (GCS), systolic blood pressure (SBP), and respiratory rate (RR)—to simplify field assessment and standardize scoring. Each parameter is assigned a numerical code from 0 to 4 based on predefined physiological ranges, reflecting degrees of derangement. These codes are derived from the original Trauma Score framework but refined using GCS for neurological evaluation.[4] For GCS, which assesses consciousness, the coding is as follows: 13–15 (mild impairment or normal) = 4 points; 9–12 (moderate impairment) = 3 points; 6–8 (severe impairment) = 2 points; 4–5 (very severe) = 1 point; and 3 (deep unconsciousness) = 0 points. SBP coding captures circulatory status: >89 mmHg (normal or near-normal) = 4 points; 76–89 mmHg (mild hypotension) = 3 points; 50–75 mmHg (moderate hypotension) = 2 points; 1–49 mmHg (severe hypotension) = 1 point; and 0 mmHg (no palpable pulse) = 0 points. RR coding evaluates ventilatory function: 10–29 breaths per minute (normal range) = 4 points; >29 breaths per minute (tachypnea) = 3 points; 6–9 breaths per minute (bradypnea) = 2 points; 1–5 breaths per minute (severe bradypnea) = 1 point; and 0 breaths per minute (apnea) = 0 points.[4][2]| Parameter | Code 4 | Code 3 | Code 2 | Code 1 | Code 0 |
|---|---|---|---|---|---|
| GCS | 13–15 | 9–12 | 6–8 | 4–5 | 3 |
| SBP (mmHg) | >89 | 76–89 | 50–75 | 1–49 | 0 |
| RR (breaths/min) | 10–29 | >29 | 6–9 | 1–5 | 0 |