Long-term, patient-centered outcomes of lower-extremity vascular trauma

Therapeutic limb hypothermia for the treatment of traumatic acute limb ischemia

Acute limb ischaemia (ALI) is an emergent clinical condition that strains pre-hospital resources and impacts healthcare costs and patient quality of life. Hypothermia has long been used in clinical and research settings to mitigate ischaemic damage in tissues, but prompt reperfusion is needed to prevent loss of limb or function from ALI. To address the unmet need for pre-hospital intervention of threatened limbs awaiting definitive specialty care, we have focused on controlled application of hypothermia. Over years of animal experiments, phantom limb creation, and materials selection, we conceptualised and created a portable limb-cooling device that can be used alone or combined with a traditional tourniquet or resuscitative endovascular balloon occlusion of the aorta. Here, we describe our process of building and testing the device, from computer simulation through animal-limb metabolic studies, to prototype testing.

Impact of Ischemia Duration on Lower Limb Salvage in Combat Casualties

INTRODUCTION

The 6-hour threshold to revascularization of an ischemic limb is ubiquitous in the trauma literature, however, contemporary evidence suggests that this threshold should be less. This study aims to characterize the relationship between the duration of limb ischemia and successful limb salvage following lower extremity arterial trauma.

METHODS

This is a cohort study of the United States and UK military service members injured while serving in Iraq or Afghanistan between 2003 and 2013. Consecutive patients who sustained iliac, femoral, or popliteal artery injuries, and underwent surgery to attempt revascularization, were included. The association between limb outcome and the duration of limb ischemia was assessed using the Kaplan-Meier method.

RESULTS

One hundred twenty-two patients (129 limbs) who sustained iliac (2.3%), femoral (56.6%), and popliteal (41.1%) arterial injuries were included. Overall, 87 limbs (67.4%) were successfully salvaged. The probability of limb salvage was 86.0% when ischemia was ≤1 hour; 68.3% when between 1 and 3 hours; 56.3% when between 3 and 6 hours; and 6.7% when >6 hours ( P <0.0001). Shock more than doubled the risk of failed limb salvage [hazard ratio=2.42 (95% confidence interval: 1.27-4.62)].

CONCLUSIONS

Limb salvage is critically dependent on the duration of ischemia with a 10% reduction in the probability of successful limb salvage for every hour delay to revascularization. The presence of shock significantly worsens this relationship. Military trauma systems should prioritize rapid hemorrhage control and early limb revascularization within 1 hour of injury.

The VA vascular injury study: A glimpse at quality of care in Veterans with traumatic vascular injury repair

OBJECTIVE

The high number of limb injuries among Post-9/11 Veterans and their long-term care pose significant challenges to clinicians. Current follow-up for extremity arterial vascular injury (EVI) is based on guideline-concordant care for treatment of peripheral vascular disease (GCC-PVD), including anticoagulant/antiplatelet or statin therapy and duplex ultrasound. No best practices exist for arterial EVI. Our goal was to determine correlates of GCC-PVD and other care among Post-9/11 Veterans with combat-related arterial EVI.

MATERIALS AND METHODS

We identified Post-9/11 Veterans with arterial EVI who underwent initial limb salvage repair or ligation (e.g., for single-vessel injury) attempt per DoD Trauma Registry validated by chart abstraction. Veterans Health Administration (VHA) data characterized the cohort in the first five years of VHA care. Models predicted (a) GCC-PVD, (b) pain clinic use, (c) mental/behavioral health care, (d) long-term opioid use, and (e) time to complication, controlling for injury severity and type, mental health parameters, and demographics.

RESULTS

The 490-Veteran cohort with validated arterial injury was 77% White averaging 25.2 years at injury (range: 18-56). Mechanism of injury was primarily explosive (63%). Veterans had Injury Severity Scores classified as mild (60%), moderate (25%) and severe (15%). Approximately 25% received at least one component of VHA GCC-PVD including 8% arterial ultrasounds, 5% statins, and 11% anticoagulants/antiplatelets; 77% had mental/behavioral healthcare. GCC-PVD, as well as PTSD and substance use disorders, were associated with receipt of mental/behavioral health care. Complications affected 46% of the cohort and were more common among those prescribed 90+ days of opioids or receiving GCC-PVD.

CONCLUSION

Despite injury severity (40% moderate/severe), only 25% of cohort patients received VHA GCC-PVD, and nearly half had complications from their arterial injury. Receiving GCC-PVD appeared to potentiate receiving care for mental and behavioral disorders.

IMPACT

The treatment gap in Veterans with arterial EVI may be due to lack of appropriate guidelines, lack of vascular specialists in VHA or accessing care outside the VHA. Focused study of care options and their outcomes will help define optimal care processes for combat Veterans with arterial EVI.

Outcomes of Revascularization and Factors Associated With Major Amputation in Patients With Lower Limb Arterial Injury: A Single-Center Retrospective Analysis

Objective To identify the amputation rates and causative factors for failed revascularization leading to amputation in patients undergoing primary limb salvage procedures for lower-extremity vascular injuries. Methods This retrospective study was conducted at the vascular surgery department, Shaheed Mohtarma Benazir Bhutto (SMBB) Institute of Trauma, Karachi, Pakistan. The data were collected from hospital record using the non-probability sampling technique. Patients aged 17-70 years, undergoing primary revascularization during April 2016 to March 2021, were included in the study. Patients with crush injuries/non-salvageable limbs underwent primary amputation, isolated deep femoral artery or crural arteries (non-limb threatening) injuries, and non-traumatic injuries like intravenous drug-induced or iatrogenic injuries were excluded. The data analysis is done using SPSS Version 20.0 (IBM Corp., Armonk, NY, USA). A P-value of <0.05 was considered as significant. Results This study includes 56 patients of mean age 30.82 ± 9.29 years with male gender four times more affected than their counterpart. About 32% of patients were smokers, while 58% of patients had no co-morbidities. All patients presented with a mean time of 7.66 ± 1.69 hours of injury with an average of 1.14 arterial segments involved. The most frequent artery involved was popliteal artery (both above and below the knee), followed by superficial femoral artery injury constituting 50% and 26%, respectively, with arterial laceration and transection being common findings on exploration. Out of 56 patients, 27 (48.2%) had open fractures, 21 (37.5% ) closed fractures, and eight patients (14.3 % ) presented with dislocation as associated injuries. Following the procedure, secondary amputation was recorded in 18 (32.1%) patients. Thrombosis and infection were the leading causes of revascularization failure. Type of injury, segment of arterial injury, and associated bony injuries were associated with limb amputation. Conclusion Type and site of injury along with concomitant bony injuries are associated with major amputations after revascularization in lower-extremity arterial injuries.

Health Outcomes Used to Determine Facets of Health-related Quality of Life for Post-9/11 Veterans Using Assistive Technology for A Combat-related Mobility Impairment: A Literature Review

INTRODUCTION

Novel rehabilitation methods, including distribution and adoption of assistive technology for lower extremity impairments, are becoming crucial to ensure positive quality of life in all individuals. The quality of life of post-9/11 combat veterans is not well understood, in comparison to research on other populations. The following essay describes a review on health outcomes used to determine health-related quality of life (HR-QoL) among combat-injured service members who require mobility-related assistive technology.

MATERIALS AND METHODS

Reviews pooled data from research on PubMed, EMBASE, CINAHL, and PsycINFO published after September 11, 2001, and included service members who sustained a mobility impairment because of involvement in a post-9/11 combat operation. Basic descriptors were extracted in addition to health outcomes used, which were then categorized and summarized by six domains for HR-QoL as defined by the World Health Organization.

RESULTS

This review found health outcomes that fit in the pain and discomfort, negative emotions, mobility, social relations, access to and quality of healthcare services, and religious/spiritual/personal beliefs subdomains. The categorized results detailed their application to track and model HR-QoL health states in those with mobility impairments using mobility-based assistive technology.

CONCLUSIONS

The research on combat-induced mobility impairments indicates assistive technology improves otherwise poor health states. The results model these domains and subdomains to determine overall HR-QoL and the quality of a healthcare intervention, though additional research is needed as only one study was identified to be experimental in design.

Patency of arterial repairs from wartime extremity vascular injuries

BACKGROUND

Extremity vascular injury (EVI) causes significant disability in Veterans of the Afghanistan/Iraq conflicts. Advancements in acute trauma care improved survival and decreased amputations. The study of wartime EVI has relied on successful limb salvage as a surrogate for vascular repair. We used imaging studies as a specific measure of arterial repair durability.

METHODS

Service members with EVI were identified using the Department of Defense Trauma Registry and validated by chart abstraction. Inclusion criteria for the arterial patency subgroup included an initial repair attempt with subsequent imaging reports (duplex ultrasound, CT angiography, and angiogram) documenting initial patency.

RESULTS

The cohort of 527 included 140 Veterans with available imaging studies for 143 arterial repairs; median follow-up from injury time to last available imaging study was 19 months (Q1-Q3: 3-58; range: 1-175). Injury mechanism was predominantly explosions (52%) and gunshot wounds (42%). Of the 143 arterial repairs, 81% were vein grafts. Eight repairs were occluded, replaced or included in extremity amputations. One upper extremity and three transtibial late amputations were performed for chronic pain and poor function averaging 27 months (SD: 4; range: 24-32). Kaplan-Meier analysis estimated patency rates of 99%, 97%, 95%, 91% and 91% at 3, 6, 12, 24, and 36 months, respectively, with similar results for upper and lower extremity repairs. Explosive and gunshot wound injury mechanisms had similar patency rates and upper extremity injuries repaired with vein grafts had increased patency.

CONCLUSIONS

Arterial repair mid-term patency in combat-related extremity injuries is excellent based on imaging studies for 143 repairs. Assertive attempts at acute limb salvage and vascular repair are justified with decisions for amputation versus limb salvage based on the overall condition of the patient and degree of concomitant nerve, orthopedic and soft tissue injuries rather than the presence of arterial injuries.

LEVEL OF EVIDENCE

Therapeutic/care management, level IV.

Persistent Pain, Physical Dysfunction, and Decreased Quality of Life After Combat Extremity Vascular Trauma

BACKGROUND

Combat-related extremity vascular injuries (EVI) have long-lasting impact on Iraq/Afghanistan veterans. The purpose of this study is to describe long-term functional outcomes in veterans with EVI using survey measures and identify modifiable factors that may be improved to reduce chronic pain and injury-related dysfunction.

METHODS

Veterans with upper and lower EVI undergoing an initial limb salvage attempt were identified using the Department of Defense Trauma Registry and validated with chart abstraction. Surveys measured pain; Short Musculoskeletal Function Assessment (SMFA) for self-reported bother and dysfunction; and Veterans RAND 12-Item Health Survey (VR-12) physical and mental component scores (PCS; MCS) for quality of life, depression, post-traumatic stress disorder, and the potentially modifiable factors of reintegration into civilian life, resilient coping, resilience, and family functioning.

RESULTS

Eighty-one patients responded with an average time since injury of 129 months (SD: 31; range 67-180 months). Mechanism of injury included 64% explosions and 31% gunshot wounds; 16% of the respondents were diagnosed with moderate/severe/penetrating traumatic brain injury. Limb salvage rates were 100% and 77% for upper and lower extremities, respectively (P = 0.004). Respondents screened positive for probable depression (55%) and post-traumatic stress disorder (51%). Compared with population norms, SMFA bother and dysfunction indices were higher (worse), MCS was lower (worse), and PCS was similar. The multivariable models adjusted for age, marital status and pain. The higher SMFA is part of the results of the multivariable models. MCS decreased with difficulty reintegrating into civilian life and was positively correlated with increased resilience and resilient coping. SMFA scores were greater for patients with high pain intensity and increased 6-11 points per point increase in difficulty with civilian-life reintegration. SMFA dysfunction was associated with better family functioning.

CONCLUSIONS

EVI results in significant long-term disability with lasting deficits in physical function, frequent depressive symptoms, and below average self-reported quality of life. Strengthening modifiable factors including resiliency and resilient coping, and providing ongoing assistance to improve reintegration into civilian life, may ameliorate the functional disabilities and chronic pain experienced by veterans with EVI.

Predictors and timing of amputations in military lower extremity trauma with arterial injury

INTRODUCTION

Military lower extremity arterial injuries present threats to life and limb. These injuries are common and limb salvage is a trauma system priority. Understanding the timing and predictors of amputation through the phases of casualty evacuation can help inform future limb salvage efforts. This study characterizes limbs undergoing amputation at different operationally relevant time points.

METHODS

A retrospective cohort study of casualties with lower extremity arterial injuries undergoing initial vascular limb salvage in Iraq and Afghanistan was undertaken. Amputations were grouped as having been performed early (in theater at Role 2 or 3) or late (after evacuation to Role 4 or 5). Further distinction was made between late and delayed (after discharge from initial hospitalization) amputations.

RESULTS

Four hundred fifty-five casualties met inclusion criteria with 103 amputations (23%). Twenty-one (20%) were performed in theater and 82 (80%) were performed following overseas evacuation. Twenty-one (26% of late amputations) were delayed, a median of 359 days from injury (interquartile range, 176-582). Most amputations were performed in the first 4 days following injury. Amputation incidence was highest in popliteal injuries (28%). Overall, amputation was predicted by higher incidence of blast mechanism and fracture and greater limb and casualty injury severity. Early amputations had higher limb injury severity than late amputations. Delayed amputations had greater incidence of motor and sensory loss and contracture than early amputations.

CONCLUSION

Casualty and limb injury severity predict predictors and timing of amputation in military lower extremity arterial injury. Amputation following overseas evacuation was more common than in-theater amputation, and functional loss is associated with delayed amputation. Future limb salvage efforts should focus on postevacuation and rehabilitative care.

LEVEL OF EVIDENCE

Epidemiologic study, level III.

Limb Salvage Does Not Predict Functional Limb Outcome after Revascularization for Traumatic Acute Limb Ischemia

BACKGROUND

Traumatic vascular injury leading to acute limb ischemia (ALI) is an uncommon problem with a potential for high morbidity. We describe a contemporary series of patients with traumatic ALI managed primarily by vascular surgeons at a tertiary referral center and review factors associated with limb salvage and functional limb outcomes.

METHODS

We conducted a single institution, retrospective review of all patients requiring revascularization for upper extremity (UE) and lower extremity (LE) ALI secondary to trauma from 2013 to 2016. Demographic data, transfer timing, injury severity score (ISS), Rutherford classification (RC), preoperative imaging, level of occlusion, procedural information, fasciotomy characteristics, and discharge disposition were reviewed. Outcome measures included limb salvage and functional limb outcomes.

RESULTS

We identified 68 patients with traumatic ALI requiring revascularization. The majority of patients had moderate ISS scores, were RC 2a or 2b on presentation (65%), were transferred from another institution (53%), and underwent preoperative imaging (62%) with expeditious time to operation (median 4.5 hr). The most common location of vascular injury for UE was axillary-brachial (88%) and for LE was femoral-popliteal (69%). Open vascular procedures dominated the treatment strategy, and the median number of operations was 3. Fasciotomy was performed in 25% of UE and 58% of LE injuries. Shunts were utilized in only 2 patients. Overall LS was 94% for UE and 78% for LE. The median length of stay (LOS) was 11 days, with 25% of patients discharged to a skilled nursing facility. Follow-up was obtained for 59% of patients. For UE injuries, 57% of patients had no or minimal functional deficits, while 33% had major functional deficits and 10% underwent amputation. For LE injuries, 68% of patients had no or minimal functional deficits, while 6% had major functional deficits, and 26% had undergone amputation. Rutherford class and the number of operations performed were independent predictors of amputation and functional limb at follow-up in our logistic regression model (P < 0.05).

CONCLUSIONS

Revascularization for traumatic ALI yields high limb salvage rates in patients with RC 1 and 2 ischemia and patients with UE injuries. However, limb salvage does not necessarily equate to good functional outcomes. This signifies the complex nature of injuries in this patient population, especially when multiple operations are required.