4: Prolonged Tourniquet Use Following Blast Related Lower Extremity Injuries Increase Heterotopic Ossification in a Pre-clinical Model

BackgroundTraumatic heterotopic ossification (tHO) is characterized by ectopic bone formation in extra-skeletal sites leading to impaired wound healing, entrapment of neurovascular structures, pain, and reduced range of motion. HO has become a signature pathology affecting wounded military personnel who have sustained blast-associated traumatic amputations during the recent conflicts in Iraq and Afghanistan and can compound recovery by causing difficulty with prosthesis limb wearing. Tourniquet use to control catastrophic limb hemorrhage prior to surgery has become almost ubiquitous during this time, with the recognition the prolonged use may risk an ischemia reperfusion injury and associated complications. While many factors influence the formation of tHO, the extended use of tourniquets to limit catastrophic hemorrhage during prolonged field care has not been explored.MethodsUtilizing an established pre-clinical model of blast-associated complex lower limb injury and traumatic amputation, we evaluated the effects of tourniquet use on tHO formation. Adult male rats were subjected to blast overpressure exposure, femur fracture, and soft tissue crush injury. Pneumatic tourniquet (250–300 mmHg) applied proximal to the injured limb for 150-min was compared to a control group without tourniquet, before a trans-femoral amputation was performed. Outcome measures were volume to tHO formation at 12 weeks and changes in proteomic and genomic markers of early tHO formation between groups.ResultsAt 12 weeks, volumetric analysis with microCT imaging revealed a 70% increase in total bone formation (p = 0.007) near the site of injury compared to rats with no tourniquet time in the setting of blast-injuries. Rats subjected to tourniquet usage had increased expression of danger-associated molecular patterns (DAMPs) and end organ damage as early as 6 h and as late as 7 days post injury. The expressions of pro-inflammatory cytokines and chemokines and osteochondrogenic genes using quantitative RT-PCR similarly revealed increased expression as early as 6 h post injury, and these genes along with hypoxia associated genes remained elevated for 7 days compared to no tourniquet use.ConclusionThese findings suggest that tourniquet induced ischemia leads to significant increases in key transcription factors associated with early endochondral bone formation, systemic inflammatory and hypoxia, resulting in increased HO formation.

Up to 9% of casualties killed in action during the Vietnam War died from exsanguination from extremity injuries. Retrospective reviews of prehospital tourniquet use in World War II and by the Israeli Defense Forces revealed improvements in extremity hemorrhage control and very few adverse limb outcomes when tourniquet times are less than 6 hours. We hypothesized that prehospital tourniquet use decreased hemorrhage from extremity injuries and saved lives, and was not associated with a substantial increase in adverse limb outcomes. This was an institutional review board-approved, retrospective review of the 31st combat support hospital for 1 year during Operation Iraqi Freedom. Inclusion criteria were any patient with a traumatic amputation, major extremity vascular injury, or documented prehospital tourniquet. Among 3,444 total admissions, 165 patients met inclusion criteria. Sixty-seven patients had prehospital tourniquets (TK); 98 patients had severe extremity injuries but no prehospital tourniquet (No TK). Extremity Acute Injury Scores were the same (3.5 TK vs. 3.4 No TK) in both groups. Differences (p < 0.05) were noted in the numbers of patients with arm injuries (16.2% TK vs. 30.6% No TK), injuries requiring vascular reconstruction (29.9% TK vs. 52.5% No TK), traumatic amputations (41.8% TK vs. 26.3% No TK), and in those patients with adequate bleeding control on arrival (83% TK vs. 60% No TK). Secondary amputation rates (4 (6.0%) TK vs. 9 (9.1%) No TK); and mortality (3 (4.4%) TK vs. 4 (4.1%) No TK) did not differ. Tourniquet use was not deemed responsible for subsequent amputation in severely mangled extremities. Analysis revealed that four of seven deaths were potentially preventable with functional prehospital tourniquet placement. Prehospital tourniquet use was associated with improved hemorrhage control, particularly in the worse injured (Injury Severity Score >15) subset of patients. Fifty-seven percent of the deaths might have been prevented by earlier tourniquet use. There were no early adverse outcomes related to tourniquet use.

Two other competencies(Table 1), although not necessarily new to the list ofimmediate emergency management care skills, do requirefurther examination based on the current available scienceand standard of care in prehospital medicine. The purposeof this column is to provide athletic training educators(ATE) with evidence regarding the use of tourniquets in theprehospital setting as well as to be a resource on how toteach the management of external hemorrhage usingtourniquets.Trauma resulting in disruption of soft tissue is classified asan open or closed wound, and any significant loss ofintravascular volume may lead sequentially to hemodynam-ic instability, decreased tissue perfusion, cellular hypoxia,organ damage, and death.

Use of the HemaClear™ elastic tourniquet reduces blood loss in operative treatment of humeral shaft fractures

To provide insight into the implications of prolonged tourniquet use on the battlefield, ultimately contributing to the optimization of clinical practices in military and civilian healthcare settings. Design: Retrospective observational study. Two academic Level I Trauma Centers. Adults who suffered high-energy battlefield injuries to the limbs on October 7th, 2023, with prolonged battlefield tourniquet application (>4h). Patients who underwent immediate limb amputation upon arrival at the hospital were excluded. Clinical outcomes including hemodynamic status, vascular repairs, rhabdomyolysis, renal injury, infection, nerve injury, amputation, and functional outcomes were reviewed. Eighteen patients (mean age 24 years; range 19-50 years) with 21 high-energy limb injuries and>4h tourniquet application were included (100% male); 9 (42.9%) upper limb injuries, and 12 (57.1%) lower limb injuries. The mean age of the cohort was 24 (SD 8.9, range 19-50). The mean tourniquet time was 5.8h (SD 1.2, range 4-9h). All of the patients (100%) underwent urgent fasciotomies upon arrival. Five patients (27.8%) required vascular repair. Seven patients (38.9%) developed temporary acute kidney injury (AKI), 2 patients (11.1%) required hemodialysis. Eight patients (44.4%) developed bacterial infections and required additional surgical interventions. Of these eight, limb salvage occurred in 6 (33.3%) and the remaining 2 (11.1%) underwent limb amputation. A total of 5 patients (27.8%) ultimately underwent amputation, all of which were lower limb amputations. Sixteen patients (88.9%) sustained lingering nerve injuries. The average Upper Extremity Functional Index (UEFI) score was 40.6 (SD 14.9 range 30-57) and the average Lower Extremity Functional Index (LEFI) was 42.3 (SD 20.1, range 14-68), indicating moderate functional limitation1,2. Longer tourniquet time was associated with a higher complication rate. CPK levels increased with each additional hour, and 100% of the patients requiring hemodialysis had tourniquet time exceeding 6 h. Additionally, 80% of amputation and 75% of infections occurred when tourniquet time exceeded 6 h. In a cohort of 18 patients with 21 high-energy limb injuries, a tourniquet time >4h did not preclude limb salvage, with an overall amputation rate of 23.8%. Tourniquet times exceeding 6 hours were associated with higher rates of complications. A level IV retrospective study.

Patient-reported outcome measures (PROMs) are tools for assessing symptoms and the quality of care. Despite their growing use, conventional data collection methods limit widespread PROM implementation. In orthopedics, pain is a frequent patient complaint and a common PROM, especially following total knee arthroplasty (TKA). Although TKA is generally successful, some patients still report postoperative pain, potentially due to tourniquet use. Using an improved PROM data-gathering technique may help to address tourniquet use during a TKA procedure and its impact on postoperative pain. The PainPad, an automated self-logging device, was developed to capture patient pain levels accurately. The aim of the study is to assess the feasibility and effectiveness of the PainPad device in quantifying in-hospital postoperative pain following TKA with or without tourniquet use. A retrospective study with 234 patients who underwent TKA from 2018 to 2021 at Milton Keynes University Hospital was conducted. Patients were categorized as receiving TKA with an intraoperative tourniquet (tourniquet group) or TKA without a tourniquet (nontourniquet group). Postoperative pain during the first 24 hours was self-reported every 2 hours using the PainPad device. From both groups, data on hospital length of stay, total tourniquet time, and the presence of postoperative deep vein thrombosis were also collected. There were 115 TKAs with tourniquets (72/115, 62.6% female patients; mean age 69.26, SD 9.93 years) and 119 TKAs without tourniquets (91/119, 76.4% female patients; mean age 70.97, SD 9.01 years). When assessing 24-hour mean postoperative pain scores, the PainPad device data indicated no significant difference (P=.53; 95% CI -0.76 to 0.39) between the tourniquet (mean pain score 3.31, SD 2.34) and nontourniquet groups (mean pain score 3.12, SD 2.15). There was no correlation between tourniquet times and the pain scores retrieved from the PainPad device. A subgroup analysis comparing longer (>90 minutes) versus shorter (<90 minutes) tourniquet times showed no significant difference in terms of pain and length of stay. The PainPad device is a feasible and effective method for collecting and evaluating in-hospital postoperative pain following TKA, allowing for the quantification of individual pain levels. This study aligns with the current health care trend toward leveraging innovative technologies and personalized data to enhance patient-centered care.

BackgroundTourniquets are crucial for controlling life-threatening hemorrhage and, therefore, in preventing avoidable deaths in both military and civilian settings. Its increased use since the launch of the Stop the Bleed campaign, however, has raised concerns regarding possible complications associated with its application, including limb ischemia and amputation. The objective of this study was to synthesize the existing evidence regarding complications associated with the use of tourniquets for extremity injuries and identify gaps in knowledge to guide future research on this topic.MethodsA review of the literature between 2016 and 2024 was performed including open access retrospective studies, case series, clinical cases, and systematic reviews that addressed tourniquet use in a civilian or military setting in patients with extremity injuries, following the PRISMA-ScR 2018 checklist. PubMed, ScienceDirect, and Cochrane databases were queried, identifying 1,398 articles on the use of extremity tourniquets in military and civilian contexts, focusing on complications. Of these, 1,343 articles were excluded due to duplication or irrelevance based on the title. From the 55 remaining, 37 were excluded after abstract review for not meeting inclusion criteria. Of the 18 full-text articles reviewed, 10 were excluded due to insufficient data, leaving 8 studies for detailed analysis.ResultsProlonged application in emergency situations may lead to severe complications, such as nerve injuries, post-tourniquet syndrome and thromboembolic event risks. Nerve palsy has been identified as the most prevalent complication associated with prolonged tourniquet use.ConclusionImproved training is essential to help providers accurately assess bleeding severity and apply appropriate interventions, reducing complications and enhancing outcomes. Future research opportunities should consider: (1) prospective interventional randomized controlled studies aiming to compare the use of tourniquets to different methods of hemorrhage control; (2) development and validation of easy-to-use scores predicting complications and the need of amputation in both civilian and military settings including upper and lower extremities, to better guide clinical decisions and future guidelines; (3) development of better ways to teach lay providers to recognize life threatening bleeding; and (4) development of guidelines for timing of tourniquet loosening, removal or conversion.

A pneumatic tourniquet is often used during ankle fracture surgery to reduce bleeding and enhance the visibility of the surgical field. Tourniquet use causes both mechanical and ischemic pain. The main purpose of this study was to evaluate the effect of tourniquet time on postoperative opioid consumption after ankle fracture surgery. We retrospectively reviewed the files of 586 adult patients with surgically treated ankle fractures during the years 2014-2016. We evaluated post hoc the effect of tourniquet time on postoperative opioid consumption during the first 24 h after surgery. The patients were divided into quartiles by the tourniquet time (4-43 min; 44-58 min; 59-82 min; and≥83 min). Multivariable linear regression analysis was used to evaluate the results. Tourniquets were used in 486 patients. The use of a tourniquet was associated with an increase in the total postoperative opioid consumption by 5.1 mg (95 % CI 1.6-8.5; p=0.004) during the first 24 postoperative hours. The tourniquet time over 83 min was associated with an increase in the mean postoperative oxycodone consumption by 5.4 mg (95 % CI 1.2 to 9.7; p=0.012) compared to patients with tourniquet time of 4-43 min. The use of a tourniquet and prolonged tourniquet time were associated with higher postoperative opioid consumption during the 24h postoperative follow-up after surgical ankle fracture fixation. The need for ethical approval and informed consent was waived by the Institutional Review Board of Northern Ostrobothnia Health District because of the retrospective nature of the study.

The evolving warfare tactics used by near-peer adversaries are expected to increase the incidence of severe extremity injuries and delayed evacuations. Initial reports from combat in Ukraine suggest high complication rates associated with prolonged tourniquet use. This study aimed to evaluate the systemic effects of limb reperfusion following tourniquet application lasting 4 hours or more in patients with isolated extremity injuries. Patients were treated according to an evidence-based protocol designed to mitigate ischemia-reperfusion injuries. This retrospective review was conducted at a forward surgical facility in Ukraine during combat operations from May 2023 to February 2024. Patients with tourniquets in place for at least 4 hours were included, while those with contraindications to limb salvage or significant confounding injuries were excluded. Short-term outcomes assessed included limb salvage, organ failure, and survival rates. Of the 1,945 casualties screened, 90 (4.6%) met the inclusion criteria. After excluding 16 patients, outcomes were analyzed for 74 males, with an average age of 41.6 ± 8.5 years and a mean tourniquet duration of 7.1 ± 2.9 hours. Among these, 19 patients (25.67%) had vascular injuries, and compartment syndrome was present in all cases. Hemodialysis was required for 58 patients (70.8%), while 27 (36.3%) needed a delayed limb amputation, and 5 patients (6.7%) died. Patients requiring dialysis underwent an average of 3 ± 2 sessions to recover kidney function. Longer tourniquet times increased the need for dialysis, which increased the likelihood of patient death. We used a standardized ischemia-reperfusion algorithm to reduce the systemic effects of ischemia and reperfusion during attempts to salvage limbs following 4 hours or more of tourniquet time. Preliminary outcomes indicate that survival is probable, kidney function may improve with brief periods of dialysis, and limb salvage is possible in most cases. Therapeutic/Care Management; Level IV.

ObjectivesThe aim of this study was to evaluate the effects of tranexamic acid (TXA) administration on bleeding control and to compare its utilization with and without simultaneous use of conventional pneumatic tourniquets during total knee arthroplasty (TKA).Patients and methodsBetween January 2017 and December 2017, a total of 204 patients (23 males, 181 females; mean age: 66±6.9 years; range, 45 to 86 years) who underwent TKA for Stage 4 gonarthrosis were retrospectively analyzed. The patients were divided into two groups as those with (n=110) and without (n=94) pneumatic tourniquet use. Tranexamic acid (1 g) was administered intravenously to all patients in both study groups. Intra- and postoperative blood loss were calculated, and postoperative pain was evaluated by a Visual Analog Scale. Demographic and clinical data were compared between the study groups.ResultsThe amount of total blood loss and postoperative blood loss were significantly higher in the tourniquet group than that in the no-tourniquet group (589.4±69.5 mL vs. 490.8±55.2 mL and 326±56 mL vs. 164±35.5, respectively; p<0.001 for both). Intraoperative blood loss was significantly higher in the no-tourniquet group (326.9±42.9 mL vs. 263.5±53.8 mL, respectively; p<0.001). The pain score at 24 h was significantly higher in the tourniquet group (p<0.001).ConclusionTotal blood loss and postoperative pain were significantly higher among patients in whom a tourniquet was used during TKA. Therefore, the routine use of tourniquets with TXA should be reconsidered.

Use of a pneumatic tourniquet in total knee arthroplasty increases the risk of distal deep vein thrombosis: A prospective, randomized study

Tourniquet use for extremity hemorrhage control has seen a recent increase in civilian usage. Previous retrospective studies demonstrated that tourniquets improve outcomes for major extremity trauma (MET). No prospective study has been conducted to date. The objective of this study was to evaluate outcomes in MET patients with prehospital tourniquet use. We hypothesized that prehospital tourniquet use in MET decreases the incidence of patients arriving to the trauma center in shock. Data were collected prospectively for adult patients with MET at 26 Level I and 3 Level II trauma centers from 2015 to 2020. Limbs with tourniquets applied in the prehospital setting were included in the tourniquet group and limbs without prehospital tourniquets were enrolled in the control group. A total of 1,392 injured limbs were enrolled with 1,130 tourniquets, including 962 prehospital tourniquets. The control group consisted of 262 limbs without prehospital tourniquets and 88 with tourniquets placed upon hospital arrival. Prehospital improvised tourniquets were placed in 42 patients. Tourniquets effectively controlled bleeding in 87.7% of limbs. Tourniquet and control groups were similarly matched for demographics, Injury Severity Score, and prehospital vital signs (p > 0.05). Despite higher limb injury severity, patients in the tourniquet group were less likely to arrive in shock compared with the control group (13.0% vs. 17.4%, p = 0.04). The incidence of limb complications was not significantly higher in the tourniquet group (p > 0.05). This study is the first prospective analysis of prehospital tourniquet use for civilian extremity trauma. Prehospital tourniquet application was associated with decreased incidence of arrival in shock without increasing limb complications. We found widespread tourniquet use, high effectiveness, and a low number of improvised tourniquets. This study provides further evidence that tourniquets are being widely and safely adopted to improve outcomes in civilians with MET. Therapeutic/Care Management; Level IV.

Letter to the Editor

Civilian Prehospital Tourniquet Use Is Associated with Improved Survival in Patients with Peripheral Vascular Injury

Tourniquet Use for Short Hand Surgery Procedures Done Under Local Anesthesia Without Epinephrine