Evaluating tourniquet use in Swedish prehospital care for civilian extremity trauma

Tourniquet Use in the Prehospital Setting

PURPOSE

Tourniquets are a mainstay of life-saving hemorrhage control. The US military has documented the safety and effectiveness of tourniquet use in combat settings. In civilian settings, events such as the Boston Marathon bombing and mass shootings show that tourniquets are necessary and life-saving entities that must be used correctly and whenever indicated. Much less research has been done on tourniquet use in civilian settings compared to military settings. The purpose of this study is to describe the prehospital use of tourniquets in a regional EMS system served by a single trauma center.

METHODS

All documented cases of prehospital tourniquet use from 2015 to 2020 were identified via a search of EMS, emergency department, and inpatient records, and reviewed by the lead investigator. The primary outcomes were duration of tourniquet placement, success of hemorrhage control, and complications; secondary outcomes included time of day (by EMS arrival time), transport interval, extremity involved, who placed/removed the tourniquet, and mechanism of injury.

RESULTS

Of 182 patients with 185 tourniquets applied, duration of application was available for 52, with a median (IQR) of 43 (56) minutes. Hemorrhage control was achieved in all but two cases (96%). Three cases (5.8%) required more than one tourniquet. Complications included five cases of temporary paresthesia, one case of ecchymosis, two cases of fasciotomy, and two cases of compression nerve injury. The serious complication rate was 7.7% (4/52). Time of day was daytime (08:01-16:00) = 15 (31.9%), evening (16:01-00:00) = 27 (57.4%), and night (00:01- 08:00) = 5 (10.6%). The median transport interval was 22 (IQR 5] minutes. The limbs most often injured were the left and right upper extremities (15 each). EMS clinicians and police officers were most often the tourniquet placers. Common mechanisms of injury included gunshot wounds, motorcycle accidents, and glass injuries.

CONCLUSION

Tourniquets used in the prehospital setting have a high rate of hemorrhage control and a low rate of complications.

Impact of time and distance on outcomes following tourniquet use in civilian and military settings: A scoping review

BACKGROUND

The last two decades have seen the reintroduction of tourniquets into guidelines for the management of acute limb trauma requiring hemorrhage control. Evidence supporting tourniquet application has demonstrated low complication rates in modern military settings involving rapid evacuation timeframes. It is unclear how these findings translate to patients who have prolonged transport times from injury in rural settings. This scoping review investigates the relationship between time and distance on metabolic complications, limb salvage and mortality following tourniquet use in civilian and military settings.

METHODS

A systematic search strategy was conducted using PubMed, Embase, and SafetyLit databases. Study characteristics, setting, mechanism of injury, prehospital time, tourniquet time, distance, limb salvage, metabolic response, mortality, and tourniquet removal details were extracted from eligible studies. Descriptive statistics were recorded, and studies were grouped by ischemia time (< 2 h, 2-4 h, or > 4 h).

RESULTS

The search identified 3103 studies, from which 86 studies were included in this scoping review. Of the 86 studies, 55 studies were primarily in civilian environments and 32 were based in military settings. One study included both settings. Blast injury was the most common mechanism of injury sustained by patients in military settings (72.8% [5968/8200]) followed by penetrating injury (23.5% [1926/8200]). In contrast, in civilian settings penetrating injury was the most common mechanism (47.7% [1633/3426]) followed by blunt injury (36.4% [1246/3426]). Tourniquet time was reported in 66/86 studies. Tourniquet time over four hours was associated with reduced limb salvage rates (57.1%) and higher mortality rates (7.1%) compared with a tourniquet time of less than two hours. The overall limb salvage and mortality rates were 69.6% and 6.7% respectively. Metabolic outcomes were reported in 28/86 studies with smaller sample sizes and inconsistencies in which parameters were reported.

CONCLUSION

This scoping review presents literature describing comparatively safe tourniquet application when used for less than two hours duration. However, there is limited research describing prolonged tourniquet application or when used for protracted distances, such that the impact of tourniquet release time on metabolic outcomes and complications remains unclear. Prospective studies utilizing the development of an international database to provide this dataset is required.

Tourniquet Application for Bleeding Control in a Rural Trauma System: Outcomes and Implications for Prehospital Providers

Introduction: Uncontrolled bleeding is a preventable cause of death in rural trauma. Herein, we examined the appropriateness, effectiveness, and safety of tourniquet application for bleeding control in a rural trauma system.Methods: Medical records of adult patients admitted to our academic Level I trauma center between July 2015 and December 2018 were retrospectively reviewed. Demographics (age, gender), injury (Injury severity score, Glascow Coma scale, mechanism of injury), tourniquet (type, tourniquet application site, tourniquet duration, place of application and removal, indication), and outcome data (complications such as amputation, acute kidney injury, rhabdomyolysis, or nerve palsy and mortality) were collected. Tourniquet indications, effectiveness, and complications were evaluated. Data were compared to those in urban settings.Results: Ninety-two patients (94 tourniquets) were identified, of which 58.7% incurred penetrating injuries. Eighty-seven tourniquets (92.5%) were applied in the prehospital setting. Twenty tourniquets (21.3%) were applied to patients without an appropriate indication. Two of these tourniquets were applied in a hospital setting, while 18 occurred in the prehospital setting (p = 0.638). Patients with a non-indicated tourniquet presented with a higher hemoglobin level on admission, received less packed red blood cell units within the first 24 hours of hospitalization, and were less likely to require surgery for hemostasis. None of the non-indicated tourniquets led to a complication. Indicated tourniquets were deemed ineffective in seven cases (9.5%); they were all applied in the prehospital setting. The average tourniquet time was 123 min in rural vs. 48 min in urban settings, p < 0.001. There was no significant difference in mortality, amputation rates and incidence of nerve palsy between the rural and urban settings.Conclusion: Even with long transport times, early tourniquet application for hemorrhage control in rural settings is safe with no significant attributable morbidity and mortality compared to published studies on urban civilian tourniquet use. The observed rates of non-indicated and ineffective tourniquets indicate suboptimal tourniquet usage and application. Opportunity exists for standardized hemorrhage control training on the use of direct pressure and pressure dressings, indications for tourniquet use, and effective tourniquet application.

Increased Use of Prehospital Tourniquet and Patient Survival: Los Angeles Countywide Study

BACKGROUND

Recent trends in prehospital tourniquet use remain underreported. In addition, the impact of prehospital tourniquet use on patient survival has not been evaluated in a population-level study. We hypothesized that prehospital tourniquets were used more frequently in Los Angeles County and their use was associated with improved patient survival.

STUDY DESIGN

This is a retrospective cohort study using a database maintained by the Los Angeles County Emergency Medical Services Agency. We included patients who sustained extremity vascular injuries between October 2015 and July 2019. Patients were divided into the following study groups: prehospital tourniquet and no-tourniquet group. Our primary end point was in-hospital mortality. The secondary outcomes included 4- and 24-hour transfusion requirements and delayed amputation.

RESULTS

A total of 944 patients met our inclusion criteria. Of those, 97 patients (10.3%) had prehospital tourniquets placed. The rate of tourniquet use increased linearly throughout our study period (goodness of fit, p = 0.014). In multivariable analysis, prehospital tourniquet use was significantly associated with improved mortality (adjusted odds ratio 0.32; 95% CI, 0.16 to 0.85; p = 0.032). Similarly, transfusion requirements were significantly lower within 4 hours (regression coefficient -547.76; 95% CI, -762.73 to -283.49; p < 0.001) and 24 hours (regression coefficient -1,389.82; 95% CI, -1,824.88 to -920.97; p < 0.001). There was no significant difference in delayed amputation rates (adjusted odds ratio 1.07; 95% CI, 0.21 to 10.88; p < 0.097).

CONCLUSIONS

Prehospital tourniquet use has been on the rise in Los Angeles County. Our results suggest that the use of prehospital tourniquets for extremity vascular injuries is associated with improved patient survival and decreased blood transfusion requirements, without an increase in delayed amputations.