Prehospital Tourniquet Use Should be a Trauma Team Activation Criterion

Abstract

Purpose:

Prehospital tourniquet application is not a standard trauma team activation (TTA) criterion recommended by the ACS COT. Tourniquet use has seen a resurgence recently with associated risks and benefits of more liberal usage. Our institution added tourniquet application as TTA criterion in January 2019. This study aimed to evaluate the effect this would have on patient care and overtriage.

Methods:

A prospective analysis was conducted for all TTA associated with tourniquets placed during 2019. An overtriage analysis was conducted utilizing a modified Cribari method as described in Resources for the Optimal Care of the Injured Patient, comparing patients that met standard TTA criteria (TTA-S), to those who met criteria due to tourniquet placement (TTA-T).

Results:

During the study, there were 46 TTA with tourniquets. Mean prehospital tourniquet time was 80 minutes. Median ISS was 10, 8 (17%) had an ISS >15. Urgent operative intervention was needed in 74%, with 23% and 21% requiring orthopedic and vascular procedures, respectively. Tourniquets were correctly placed in 80% and clinically appropriate in 57%. Of these subjects, 25 (54%) were TTA-S and 21 TTA-T. Overtriage analysis was performed. Overtriage for TTA-T was 33.3%. Overtriage among TTA-S was 4%.

Conclusion:

Patients with prehospital tourniquets are frequently severely injured. The immediate presence of a trauma surgeon can have significant impacts in these cases. This is particularly important in a rural environment with long tourniquet times. Prehospital tourniquet application as a TTA criteria does not result in excessive overtriage.

Introduction

Prehospital tourniquet application is not included in the American College of Surgeons Committee on Trauma (ACS COT) standard criteria for full trauma team activation (TTA).¹ Recommendations for and against prehospital tourniquet usage in the civilian realm have continued to evolve over the years. Current recommendations have identified improved outcomes with increased use by prehospital emergency medical services.^2–5 This has been further reinforced to the general public with the American College of Surgeons Stop the Bleed® campaign.⁶ As such, there has been a growth in prehospital tourniquet usage seen in the civilian sector.⁷

The increased use of prehospital tourniquets could result in a significant number of unindicated or inappropriately placed devices. Situated in a rural environment, our center had additional concerns about the length of time a tourniquet, while generally identified as safe for a period of up to 2 hours, might he applied prior to arrival for definitive care. Nearly 30 million Americans live in a rural environment and are more than 1 hour from a major trauma center,^8–10 enhancing the risk associated with liberal tourniquet use in a rural environment. Our institution hypothesized that prehospital tourniquet use was a marker for severe injury; therefore, it was added as a center-specific TTA criterion in January 2019 The purpose of this study was to determine whether the addition of prehospital tourniquet application as a TTA criterion appropriately identifies injured patients in need of additional resources without significantly impacting overtriage rates.

Methods

We performed a retrospective review of the trauma registry at a large, rural, ACS-verified level I trauma center. The study included all trauma patients who were a TTA and had the presence of a prehospital tourniquet over a 1-year period (January 1, 2019-Decemher 31, 2019). After obtaining approval from the West Virginia University Institutional Review Board, we queried our institutional trauma registry, which is maintained prospectively by trained trauma registrars. Registry data obtained included patient demographics, mechanism of injury, vital signs (both prehospital and on presentation), Injury Severity Scores (ISS), blood transfusion, operations, disposition following departure from the emergency department, and final discharge status. Hospital charts were reviewed to explicate the data further, clarify any missing data, and obtain specifics on operative procedures. Attending trauma surgeons are present in the hospital 24 hours a day, the attending who was present upon patient arrival was asked to identify if the tourniquet was correctly placed and clinically indicated. No exclusion criteria were used, all patient who arrived with a tourniquet during the time period were included in this study.

Patients were then stratified into those meeting standard activation criteria (TTA-S) and those that were only a TTA due to the presence of a tourniquet (TTA-T). Standard TTA criteria included confirmed systolic blood pressure (SBP) < 90 mmHg, gunshot wounds (GSWs) to the neck, chest, abdomen, or extremities proximal to the knee/elbow, Glasgow Coma Scale (GCS) < 9, any patient transferred from another institution requiring blood products to maintain vital signs, and intubated patients or those with respiratory compromise. These groups were then compared, and continuous variables were analyzed using Student’s t-test. Categorical variables were compared using Fisher’s exact test due to sample size. Statistical significance for all variables was set as P < .05.

Overtriage analysis was then conducted utilizing a modified Cribari method as described in Resources for the Optimal Care of the Injured Patient (Figure 1),¹ and the Need for Trauma Intervention (NFTI) method.¹¹ This method is based on these multiple variables: receiving packed red blood within 4 hours of arrival, ED discharge to operating room (OR) within 90 minutes, ED discharge to interventional radiology, ED discharge to intensive care unit (ICU) with ICU length of stay (LOS) ≥3 calendar days, nonprocedural mechanical ventilation within 72 hours of arrival, and mortality within 60 hours of arrival. Specific criteria were selected to identify patients with “major injury,” who would likely benefit from the trauma team’s presence on arrival. These criteria included a greater than 48-hour length of hospital stay, admission to an intensive care unit (ICU), intubation in the emergency department following presentation, urgent disposition to the operating room or catheter-based radiology suite, ISS >15, and any mortality.

Figure I.

Modified Cribari method.

Results

During the study period, 46 patients were identified with the presence of a tourniquet resulting in TTA. The majority (83%) were male, and the median age was 38 years (range: 16-77). The most common mechanisms of injury were lacerations from broken glass (20%), knife lacerations (15%), gunshot wounds (13%), and saw or chainsaw injuries (13%). Patients were then divided into cohorts where 25 (54%) were TTA-S and 21 (46%) were TTA-T. There was 1 (2%) mortality (see Table 1); this occurred in the TTA-S group and was not related to the extremity injury. The majority, 30 (65%), of tourniquet placements were on upper extremities. When examining the 2 cohorts, there was a more even distribution in the difference of upper to lower (14 to 11), in the TTA-S group than the TTA-T group (17 to 4). Median ISS was 10.0, and 8 patients (17%) had an ISS >15. Mean prehospital tourniquet time was 80 minutes (range: 10-240 minutes). Twenty-three patients (50%) had a prehospital tourniquet time over 60 minutes, and five (11%) had a tourniquet time over 120 minutes. (Table 2)

Table I.

Extended Criteria of TTA-S vs TTA-T Patients.

Extended criteria	TTA-T, %	TTA-S, %
Mortality	0 (.0)	1 (4.0)
>48 hours LOS	3 (14.3)	17 (68.0)
ICU admission	2 (9.5)	18 (72.0)
ED intubation	1 (4.8)	7 (28.0)
Urgent IR/OR	14 (66.7)	20 (80.0)
ISS > 15	1 (4.8)	7 (28.0)

LOS, length of stay; ICU, intensive care unit ED, emergency department; IR/OR, interventional radiology/operating room; ISS, Injury Severity Score.

Table 2.

Demographic Characteristics of Patients Arriving at Hospital with Tourniquets Placed.

Characteristic	All TTA (n = 46)	TTA-T (n = 21)	TTA-S (n = 25)
Age, years, median	38	38.667	37.7
Male, n	38 (82.6%)	18 (85.7%)	20 (80.0%)
ISS, median	10.0	5.4	13.6
Mechanism	16 (34.8%)	6 (28.6%)	10 (40.0%)
Blunt	30 (65.2%)	15 (71.4%)	15 (60.0%)
Penetrating
Tourniquet location	30 (65.2%)	17 (81.0%)	14 (56.0%)
Upper extremity	16 (34.8%)	4 (19.0%)	11 (44.0%)
Lower extremity
Isolated limb injury	31 (67%)	18 (66%)	13 (52%)
Hypotensive	7 (15%)	0 (.0%)	7 (28.0%)
Mean prehospital tourniquet time minutes (range)	80 (10-240)	65.3 (10-180)	93 (20-240)

ISS: Injury Severity Score.

Urgent operative intervention was needed in 74% of the patients, with 23% requiring orthopedic surgery and 21% requiring a vascular procedure. Twenty-eight percent of patients requiring urgent operative intervention had isolated distal forearm injuries with a radial and/or ulnar artery injury. The remainder required operative intervention for severe soft tissue injuries and control of hemorrhage. Tourniquets were correctly placed in 80% of cases and deemed clinically appropriate in 57%. Tourniquets taken down in the trauma bay and left released accounted for 67%. The discrepancy between the clinically appropriate tourniquets and those taken down being attributed to 5 cases of radial/ulnar artery injury that had thrombosed but was deemed clinically appropriate placement on retrospective review given the arterial injury. Six tourniquets were found to only occlude venous outflow on arrival to the hospital. No nerve injuries were identified at the level of the tourniquet. No patients required an amputation secondary to tourniquet application, and no episodes of compartment syndrome occurred.

Utilizing the modified Cribari method, we found that the overtriage rate for the entire study was 17%. The cohorts were then analyzed separately. In the TTA-T group: 1 (5%) had an ISS >15, 14 (67%) underwent immediate operative or catheter-based intervention, 1 (5%) was intubated in the ED, 2 (10%) required ICU admission, and 3 (14%) required admission for >48 hours (Table 1). Accounting for patients that met multiple categories, 7 patients did not meet extended criteria, resulting in an overtriage rate of 33% for TTA-T patients. The overtriage rate was similarly calculated among TTA-S and was 4%. Using the NFTI, we came to an identical 33% overtriage rate with the same 7 patients in the TTA-T group not meeting the NFTI criteria.

Discussion

Trauma team activation criteria are designed to identify those trauma patients who are at high risk of mortality or severe morbidity, and to mobilize available hospital personnel and resources to provide timely and adequate treatment. As with all matters in medicine, a balance must be obtained between resource utilization, system demands, and patient needs. Significant levels of overtriage lead to the inefficient use of limited resources and result in increased costs, while undertriage can lead to worse patient outcomes and delays in care. Given these concerns, the ACS COT has provided a standardized list of TTA criteria based on physiologic signs and mechanism of injury. The ACS allows individual centers to adopt additional criteria to better provide care for their local population. By focusing on high-risk populations, a trauma center can adjust TTA criteria to minimize over- and undertriage. The presence of a prehospital tourniquet is not a standard criterion provided by the ACS COT. Due in part to the rural nature of this center and the recognition of tourniquet use as a marker for severe injury, prehospital tourniquet use was made a TTA criterion. This study aimed to evaluate the effect of this additional TTA criterion on overtriage and describe its impact on patient care.

Patients who present with a prehospital tourniquet applied are frequently severely injured. This was again demonstrated in our study with a mean ISS of 10.0 and 17% of patients having an ISS >15. Despite these injuries, only 15% of all patients were a TTA due to hypotension. The early application of tourniquets likely prevented the development of hemorrhagic shock and contributed to the low mortality in this study. Tourniquets have shown improvements in outcomes and mortality through military data, demonstrating that tourniquet application after the development of shock has a significantly worse mortality than if shock is prevented.^9,12 The benefit is further demonstrated by the high level of isolated limb injury in the TTA-T group without any documented hypotension. Within this group, two-thirds would go urgently to the operating room, highlighting that many of these patients were kept from developing hemorrhagic shock through early tourniquet application. There is the added benefit of having an attending surgeon present in the trauma bay to expedite identification of injuries, evaluate the efficacy and appropriateness of the tourniquet placement, and rapidly triage the need for operative intervention. In this setting, a fellowship-trained trauma surgeon was utilized; however, the authors note that centers could adapt this triage criteria for use based on their surgeon availability.

In a rural setting, having a trauma surgeon present is crucial given the longer transport times and consequently longer tourniquet times. Many previous studies looking at civilian tourniquet use have been in the urban setting or military theater. These studies have shown tourniquet on times ranging from 33 minutes to 77 minutes.^3,4,13 These were significantly shorter than our mean prehospital tourniquet time of 80 minutes. In addition, we also encountered 5 cases of >2 hours of transport time. In a setting when transport times can routinely be longer than 1 hour, having a surgeon at the bedside to evaluate the appropriateness, accuracy of placement, and continued need for a tourniquet are critical. This immediate evaluation can limit the potential for complications due to the tourniquet. In our series, several patients were noted to have only venous occlusion and had their tourniquets removed in the trauma bay, reducing their risk of compartment syndrome.

With an addition to the TTA criteria, there is obviously concern for overtriage and, as a result, inappropriate use of finite resources. With an overtriage rate of 33% for the TTA-T group, this is within the 25-35% rate recommended in Resources for the Optimal Care of the Injured Patient.¹ The overtriage rate for the entire cohort and the TTA-S group were also within the acceptable range. This easily identified additional criterion also eliminated the possibility for undertriage in this patient population.

This study does have the standard limitations of all retrospective database and chart reviews. Additionally, patients were selected based on the presence of a prehospital tourniquet, placement of which was left up to the discretion of the prehospital providers based on West Virginia Office of Emergency Medical Services guidelines.¹⁴ No consistent data on the level of training possessed by prehospital providers were obtained, and there were incomplete data on whether patients who were transferred were evaluated by a surgeon at their initial presentation at a critical access hospital.

Prehospital tourniquet application should he considered for addition to the standard TTA criteria in similar centers. The addition of this criterion identifies patients with a likelihood for operative intervention and significant injury burden. This addition reduces undertriage and has an acceptable level of overtriage. As the Stop the Bleed® continues to expand, we predict that civilian tourniquet use in the field will continue to increase. Larger, multicenter, prospective studies will he required before this criterion can he recommended for all institutions.

Key Take-Aways.

• Presence of a tourniquet in place can be used as an institution-specific criterion for full trauma team activation without a significant increase in overtriage rates.

• Having a tourniquet in place correlates with the need of urgent operative intervention.

• Rural trauma patients have unique challenges regarding tourniquets in which a surgeon present to quickly evaluate can have an immediate impact.