Prehospital tourniquet use: An evaluation of community application and outcome

Prehospital hemorrhage management in low- and middle-income countries: A scoping review

INTRODUCTION

Low- and middle-income countries (LMICs) account for 90% of deaths due to injury, largely due to hemorrhage. The increased hemorrhage mortality burden in LMICs is exacerbated by absent or ineffective prehospital care. Hemorrhage management (HM) is an essential component of prehospital care in LMICs, yet current practices for prehospital HM and outcomes from first responder HM training have yet to be summarized.

METHODS

This review describes the current literature on prehospital HM and the impact of first responder HM training in LMICs. Articles published between January 2000 and January 2023 were identified using PMC, MEDLINE, and Scopus databases following PRISMA-ScR guidelines. Inclusion criteria spanned first responder training programs delivering prehospital care for HM. Relevant articles were assessed for quality using the Newcastle-Ottawa scale.

RESULTS

Of the initial 994 articles, 20 met inclusion criteria representing 16 countries. Studies included randomized control trials, cohort studies, case control studies, reviews, and epidemiological studies. Basic HM curricula were found in 15 studies and advanced HM curricula were found in six studies. Traumatic hemorrhage was indicated in 17 studies while obstetric hemorrhage was indicated in three studies. First responders indicated HM use in 55%-76% of encounters, the most frequent skill they reported using. Mean improvements in HM knowledge acquisition post-course ranged from 23 to 58 percentage points following training for pressure and elevation, gauze application, and tourniquet application.

CONCLUSIONS

Our study summarizes the current literature on prehospital HM in LMICs pertaining to epidemiology, interventions, and outcomes. HM resources should be a priority for further development.

Vascular imaging immediately after tourniquet removal does not increase vasospasm risk

BACKGROUND

Prehospital tourniquet use is now standard in trauma patients with diagnosed or suspected extremity vascular injuries. Tourniquet-related vasospasm is an understudied phenomenon that may confound management by causing erroneous arterial pressure indices (APIs) and abnormalities on computed tomography angiography (CTA) that do not reflect true arterial injuries. We hypothesized that shorter intervals between tourniquet removal and CTA imaging and longer total tourniquet times would be correlated with a higher likelihood of false positive CTA.

MATERIALS AND METHODS

We performed a single-institution retrospective cohort study of patients presenting to a busy, urban Level 1 Trauma Center with prehospital tourniquets from 2019 to 2021. Patients who presented with a tourniquet disengaged upon arrival or who died prior to admission to the Trauma Unit were excluded. Tourniquet duration, time between tourniquet removal and CTA imaging (CTA interval), CTA findings, and management of extremity arterial injuries were extracted. The proportion of false positive injuries on CTA was assessed for correlation with increasing time interval from tourniquet removal to CTA imaging and correlation with increasing total tourniquet time using multivariable logistic regression.

RESULTS

251 patients were identified with prehospital tourniquets. 127 underwent CTA of the affected extremity, 96 patients had an abnormal CTA finding, and 57 (45% of total CTA patients) had false positive arterial injuries on imaging. Using multivariable logistic regression, neither the CTA interval nor the tourniquet duration was associated with false positive CTA injuries. Female sex was associated with false positive injuries on CTA (OR 2.91, 95% CI: 1.01 - 8.39). Vasospasm was cited as a possible explanation by radiologists in 40% of false positive CTA reports.

CONCLUSIONS

Arterial vasospasm is a frequent finding on CTA after tourniquet use for extremity trauma, but concerns regarding tourniquet-related vasospasm should not alter trauma patient management. Neither the duration of tourniquet application nor the time interval since removal is associated with decreased CTA accuracy, and any delay in imaging does not appear to reduce the likelihood of vasospasm. These findings are important for supporting expedited care of trauma patients with severe extremity injuries.

Prehospital tourniquet application in extremity vascular trauma: Improved functional outcomes

BACKGROUND

Support for prehospital tourniquet use has increased, with recent data suggesting that tourniquet usage decreases shock without increasing limb complications. We hypothesized that prehospital tourniquet application in extremity vascular trauma, compared with no prehospital tourniquet application, is associated with lower rates of delayed amputation and better functional mobility.

METHODS

We retrospectively studied adult patients with extremity vascular trauma at an urban civilian Level 1 trauma center (June 2016-May 2021). Outcomes of interest included delayed amputation and mobility at hospital discharge, measured by the Activity Measure for Post-Acute Care "6 Clicks" Basic Mobility Score. The "6 Clicks" Basic Mobility Score was documented by physical therapy; higher scores indicate more independent mobility. Injury mechanism, initial lactate, 24-hour transfusions, mortality, and acute kidney injury were also collected. Comparisons were performed using χ2 analysis and Fisher Exact and Wilcoxon rank-sum tests.

RESULTS

Of 232 patients, prehospital tourniquet application was not associated with mortality or lactate level (both P > .05). The prehospital tourniquet application group had more transfusions, lower rates of acute kidney injury, and fewer delayed amputations (all P < .05). Ninety-one patients (45 prehospital tourniquet application and 46 without prehospital tourniquet application) were evaluated for "Moving between Bed and Chair" in the "6 Clicks" Basic Mobility Score, with patients in the prehospital tourniquet application group demonstrating higher levels of independence (P = .034).

CONCLUSION

Prehospital tourniquet application was associated with favorable outcomes, including higher functional mobility and decreased delayed amputation. This suggests that tourniquet use should be encouraged in the civilian setting to improve outcomes and reduce the risk of limb loss.

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.

Characteristics and Outcomes of Prehospital Tourniquet Use for Trauma in the United States

INTRODUCTION

The use of the extremity tourniquet in military environments has reduced preventable deaths due to exsanguinating hemorrhage, leading to increased use in civilian settings. However, the outcomes of contemporary prehospital tourniquet use in civilian settings are not well-described nationally. The objective of this study was to describe the characteristics and outcomes following prehospital tourniquet use by emergency medical services (EMS) in the United States.

METHODS

All trauma activations reported to the National EMS Information System 2019 (NEMSIS) were included. Patients who had ≥1 tourniquet applied were identified. Descriptive analyses were used to compare characteristics between tourniquet and no-tourniquet cohorts. Coarsened exact matching was performed to generate a k2k match (on age, sex, lowest-systolic blood pressure, initial patient acuity, provider's initial impression, injury mechanism, and presence of upper/lower extremity injuries) and used to compare outcomes. Trauma patients who may have potentially benefited from tourniquet application (extremity injury, shock index ≥1 and no documented tourniquet application) were identified.

RESULTS

A total of 7,161 tourniquets were applied among 4,571,379 trauma activations (1.6/1000 activations). Patients in the tourniquet cohort were younger (40 ± 18 vs 52 ± 26 mean ± SD years), more hypotensive (16.1% vs. 2.5%) and had higher initial acuity (65.0% critical/emergent vs. 20.6%) [p < 0.01 for all]. A total of 7,074 patients in the tourniquet cohort were matched with 7,074 patients in the non-tourniquet cohort. Post-match analysis revealed that the patients in tourniquet cohort had a higher final acuity (80.8% vs. 75.0%, p < 0.01), lower scene-time (15.4 ± 13.6 vs. 17.0 ± 14.2 mean ± SD minutes, p < 0.01), and higher survival-to-hospital (83.6% vs. 75.1%, p < 0.01). A total of 141,471 trauma patients who may have potentially benefited from tourniquet application were identified.

CONCLUSION

Prehospital tourniquet use by EMS in the United States is associated with lower scene-time and improved survivability to hospital. Results indicate that patients might benefit from wider tourniquet use in the civilian prehospital setting.

Tourniquets, types and techniques in emergency prehospital care: A narrative review

Massive uncontrolled hemorrhage is an important cause of preventable death in trauma. Therefore, applying an arterial tourniquet (TQ) is recommended as a pre-hospital measure to control bleeding after severe traumatic bleeding. Limb TQ applies circumferential compression proximally to the injury site to compress the arteries, resulting in blood flow and consequently hemorrhage interruption. The use of commercial tourniquets (C-TQ), which are designed, tested, and registered to control hemorrhages in pre-hospital care, is a consensus. However, they are still uncommon in many prehospital emergency services and the overall level of evidence in most studies is low. This narrative review aimed to characterize the importance of tourniquets use in prehospital emergency care and its application techniques. Furthermore, it proposes to stimulate the development of new devices, more accessible and easier to use, to suggest new directions of studies and medical education demands, with manikin and simulation development.

Prehospital extremity tourniquet placements-performance evaluation of non-EMS placement of a lifesaving device

BACKGROUND

The education of civilians and first responders in prehospital tourniquet (PT) utilization has spread rapidly. We aimed to describe trends in emergency medical services (EMS) and non-EMS PT utilization, and their ability to identify proper clinical indications and to appropriately apply tourniquets in the field.

METHODS

A retrospective cohort study was conducted to evaluate all adult patients with PTs who presented at two Level I trauma centers between January 2015 and December 2019. Data were collected via an electronic patient query tool and cross-referenced with institutional Trauma Registries. Medically trained abstractors determined if PTs were clinically indicated (limb amputation, vascular hard signs, injury requiring hemostasis procedure, or significant documented blood loss). PTs were further designated as appropriately or inappropriately applied (based on tourniquet location, venous tourniquet, greater than 2-h ischemic time). Descriptive statistics and univariate analyses were performed.

RESULTS

146 patients met inclusion criteria. The incidence of yearly PT placements increased between 2015 and 2019, with an increase in placement by non-EMS personnel (police, firefighter, bystander, and patient). Improvised PTs were frequently utilized by bystanders and patients, whereas first responders had high rates of commercial tourniquet use. A high proportion of tourniquets were placed without indication (72/146, 49%); however, the proportion of PTs placed without a proper indication across applier groups was not statistically different (p = 0.99). Rates of inappropriately applied PTs ranged from 21 to 46% across all groups applying PTs.

CONCLUSIONS

PT placement was increasingly performed by non-EMS personnel. Present data indicate that non-EMS persons applied PTs at a similar performance level of those applied by EMS. Study LevelLevel III.

A framework for the design and implementation of Stop the Bleed and public access trauma equipment programs

Traumatic injuries remain the leading cause of death for those under the age of 44 years old. Nearly a third of those who die from trauma do so from bleeding. Reducing death from severe bleeding requires training in the recognition and treatment of life-threatening bleeding, as well as programs to ensure immediate access to bleeding control resources. The Stop the Bleed (STB) initiative seeks to educate and empower people to be immediate responders and provide control of life-threatening bleeding until emergency medical services arrive. Well-planned and implemented STB programs will help ensure program effectiveness, minimize variability, and provide long-term sustainment. Comprehensive STB programs foster consistency, promote access to bleeding control education, contain a framework to guide the acquisition and placement of equipment, and promote the use of these resources at the time of a bleeding emergency. We leveraged the expertise and experience of the Stop the Bleed Education Consortium to create a resource document to help inform and guide STB program developers and implementers on the key areas for consideration when crafting strategy. These areas include (1) equipment selection, (2) logistics and kit placement, (3) educational program accessibility and implementation, and (4) program oversight, facilitation, and administration.

Prolonged tactical tourniquet application for extremity combat injuries during war against terrorism in the Sahelian strip

PURPOSE

This study reports on complications following extended tourniquet application in patients with combat extremity injuries treated by the French Military Health Service in the Sahelian strip.

METHODS

A retrospective review was performed in a French forward medical treatment facility deployed in Gao, Mali, between 2015 and 2020. All patients treated for an extremity injury with the application of at least one tourniquet for a minimum of 3 h were included. Prehospital data were injury pattern, associated shock, tourniquet location, and duration. Subsequent complications and surgical procedures performed were analyzed.

RESULTS

Eleven patients with a mean age of 27.4 years (range 21-35 years) were included. They represented 39% of all patients in whom a tourniquet was applied. They had gunshot wounds (n = 7) or multiple blast injuries (n = 4) and totaled 14 extremity injuries requiring tourniquet application. The median ISS was 13 (interquartile range: 13). Tourniquets were mostly applied proximally on the limb for a mean duration of 268 min (range 180-360 min). Rhabdomyolysis was present in all cases. The damage control surgeries included debridement, external fixation, vascular repair, and primary amputation. Ten injuries were complicated by compartment syndrome requiring leg or thigh fasciotomy in the field or after repatriation. Two severely injured patients died of their wounds, but the others had a favorable outcome even though secondary amputation was sometimes required.

CONCLUSIONS

Extended and proximal tourniquet applications led to significant morbidity related to compartment syndrome and rhabdomyolysis. Hemorrhagic shock, mass casualty incident, and tactical constraints often precluded revising the temporary tourniquet applied under fire.