The use of temporary vascular shunts in military extremity wounds: a preliminary outcome analysis with 2-year follow-up

The History and Innovations of Blood Vessel Anastomosis

Surgical technique and technology frequently coevolve. The brief history of blood vessel anastomosis is full of famous names. While the techniques pioneered by these surgeons have been well described, the technology that facilitated their advancements and their inventors deserve recognition. The mass production of laboratory microscopes in the mid-1800s allowed for an explosion of interest in tissue histology. This improved understanding of vascular physiology and thrombosis laid the groundwork for Carrel and Guthrie to report some of the first successful vascular anastomoses. In 1916, McLean discovered heparin. Twenty-four years later, Gordon Murray found that it could prevent thrombosis when performing end-to-end anastomosis. These discoveries paved the way for the first-in-human kidney transplantations. Otolaryngologists Nylen and Holmgren were the first to bring the laboratory microscope into the operating room, but Jacobson was the first to apply these techniques to microvascular anastomosis. His first successful attempt in 1960 and the subsequent development of microsurgical tools allowed for an explosion of interest in microsurgery, and several decades of innovation followed. Today, new advancements promise to make microvascular and vascular surgery faster, cheaper, and safer for patients. The future of surgery will always be inextricably tied to the creativity and vision of its innovators.

Traumatic Lower Extremity Vascular Injuries and Limb Salvage in a Civilian Urban Trauma Center

BACKGROUND

Data on management of traumatic lower extremity injuries comes largely from military experience and involves few civilian centers. This study reports on the experience of an urban trauma center and factors associated with limb loss.

METHODS

A retrospective review of lower extremity arterial injuries between 2013-2020 at an academic urban level 1 trauma center was completed. Patients with lower extremity revascularization were included in the final data analysis. Demographics, clinical variables, operative details, type of revascularization, as well as 30-day morbidity and postoperative outcomes were analyzed. The primary outcome of interest was 30-day limb loss. Secondary outcomes included postoperative complications and functional outcomes.

RESULTS

75 patients were included in our analysis. 69 were male (92%), mean age 33 ±15 years, 50 patients had penetrating trauma (67%), mean injury severity score was 15±9. 30-day limb loss was reported in 8 (11%). Factors associated with limb loss included female sex (p=0.001), high body mass index (BMI) (p=0.001), blunt injury (p=0.001), associated fractures (p=0.005), significant soft tissue injury (p=0.007), delayed repair after shunt placement (p=0.003), bypass revascularization (p=0.001), initial revascularization failure (p=0.019), and wound complications (p<0.001). Fifty-five patients had at least one return to the operating room (ROR), including 24 patients (32%) for complications related to their revascularization. These included delayed compartment syndrome (n=7), revascularization failure (n=9), bleeding (n=3), and vascular surgical wound complications (n=5). Mean length of hospital stay (LOS) for the cohort was 24±20 days with 3±3 ROR, in contrast patients who ultimately required amputation had LOS of 57±21 days with 8±4 ROR. 57 patients (76%) followed in clinic for a median 36[14-110] days, with only 32 (43%) at > 30 days. 23 reported ambulation without assistance, 9 neuromotor deficit including 1 patient that had delayed amputation.

CONCLUSION

Patients with blunt trauma and associated fracture and/or extensive soft tissue injury are at risk of limb loss. These injuries are often associated with postoperative wound complications, requiring aggressive soft tissue care that substantially increases ROR and LOS; Expectations for limb salvage in these patients should be tempered when the other associated factors with limb loss mentioned above are also present. When limb salvage is achieved, regaining full limb function remains a challenge.

Evaluating the Tactical Combat Casualty Care principles in civilian and military settings: systematic review, knowledge gap analysis and recommendations for future research

OBJECTIVES

The Tactical Combat Casualty Care (TCCC) guidelines detail resuscitation practices in prehospital and austere environments. We sought to review the content and quality of the current TCCC and civilian prehospital literature and characterize knowledge gaps to offer recommendations for future research.

METHODS

MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials were searched for studies assessing intervention techniques and devices used in civilian and military prehospital settings that could be applied to TCCC guidelines. Screening and data extraction were performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Quality appraisal was conducted using appropriate tools.

RESULTS

Ninety-two percent (n=57) of studies were observational. Most randomized trials had low risk of bias, whereas observational studies had higher risk of bias. Interventions of massive hemorrhage control (n=17) were wound dressings and tourniquets, suggesting effective hemodynamic control. Airway management interventions (n=7) had high success rates with improved outcomes. Interventions of respiratory management (n=12) reported low success with needle decompression. Studies assessing circulation (n=18) had higher quality of evidence and suggested improved outcomes with component hemostatic therapy. Hypothermia prevention interventions (n=2) were generally effective. Other studies identified assessed the use of extended focused assessment with sonography in trauma (n=3) and mixed interventions (n=2).

CONCLUSIONS

The evidence was largely non-randomized with heterogeneous populations, interventions, and outcomes, precluding robust conclusions in most subjects addressed in the review. Knowledge gaps identified included the use of blood products and concentrate of clotting factors in the prehospital setting.

LEVEL OF EVIDENCE

Systematic review, level III.

Literature review of peripheral vascular trauma: Is the era of intervention coming?

Traumatic peripheral vascular injury is a significant cause of disability and death either in civilian environments or on the battlefield. Penetrating trauma and blunt trauma are the most common forms of vascular injuries. Besides, iatrogenic arterial injury (IAI) is another pattern of vascular trauma. The management of peripheral vascular injuries has been improved in different environments and wars. There are different types of vascular injuries, such as vasospasm, contusion, intimal flaps, intimal disruption or hematoma, external compression, laceration, transection and focal wall defects, etc. The main clinical manifestations of vascular injuries are shock following massive hemorrhage and limb necrosis due to tissue and organ ischemia. Ultrasound, computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are most valuable for assessment of peripheral vascular injuries. Angiography remains the gold standard for diagnosing vascular trauma. Immediate hemorrhage control and rapid restoration of blood flow are the primary goals of vascular trauma treatment. There are many operative treatment methods for vascular injuries, such as vascular suture or ligation, vascular wall repair and vascular reconstruction with blood vessel prostheses or vascular grafts. Embolization, balloon dilation and covered stent implantation are the main endovascular techniques. Surgical operation is still the primary treatment for vascular injuries. Endovascular treatment is a promising alternative, proved to be safe and effective, and preferred selection for patients. In summary, rapid diagnosis and timely surgical intervention remain the mainstays of the treatment. However, many issues need to be resolved by further studies.

The First Aid and Hospital Treatment of Gunshot and Blast Injuries

BACKGROUND

When gunshot and blast injuries affect only a single person, first aid can always be delivered in conformity with the relevant guidelines. In contrast, when there is a dynamic casualty situation affecting many persons, such as after a terrorist attack, treatment may need to be focused on immediately life-threatening complications.

METHODS

This review is based on pertinent publications retrieved by a selective search in Medline and on the authors' clinical experience.

RESULTS

In a mass-casualty event, all initial measures are directed toward the survival of the greatest possible number of patients, in accordance with the concept of "tactical abbreviated surgical care." Typical complications such as airway obstruction, tension pneumothorax, and hemorrhage must be treated within the first 10 minutes. Patients with bleeding into body cavities or from the trunk must be given priority in transport; hemorrhage from the limbs can be adequately stabilized with a tourniquet. In-hospital care must often be oriented to the principles of "damage control surgery," with the highest priority assigned to the treatment of life-threatening conditions such as hemodynamic instability, penetrating wounds, or overt coagulopathy. The main considerations in initial surgical stabilization are control of bleeding, control of contamination and lavage, avoidance of further consequences of injury, and prevention of ischemia. Depending on the resources available, a transition can be made afterward to individualized treatment.

CONCLUSION

In mass-casualty events and special casualty situations, mortality can be lowered by treating immediately life-threatening complications as rapidly as possible. This includes the early identification of patients with lifethreatening hemorrhage. Advance preparation for the management of a masscasualty event is advisable so that the outcome can be as favorable as possible for all of the injured in special or tactical casualty situations.

Two-team management of vascular injuries concomitant with osteo-articular injuries in 36 patients over six years

BACKGROUND

Patients with both vascular and osteoarticular injuries require multidisciplinary management. Vascular injuries may be function- and/or life-threatening. The lower limbs are predominantly affected. Traffic, domestic, and work-related accidents contribute most of the cases. The primary objective of this study was to describe the management of patients with concomitant vascular and osteo-articular injuries, with special attention to the rates of amputation and fasciotomy. The secondary objective was to suggest a management sequence to optimise our surgical practice.

HYPOTHESIS

The management sequence is a crucial consideration in patients with both vascular and osteo-articular injuries.

MATERIAL AND METHODS

A 6-year, retrospective, observational study was conducted in patients with concomitant vascular and osteo-articular injuries.

RESULTS

The study included 36 patients with a mean age of 40.6±22.1 years. The main sources of injury were traffic accidents (n=19, 52.8%), crush injury (n=8, 22.2%), and falls (n=5, 13.9%). A compound fracture was present in 20 (55.6%) patients. Evidence of ischaemia in 25 (69.4%) patients, and bleeding in 11 (30.6%) patients. Pre-operative imaging, by ultrasonography or computed tomography, was performed in 27 (75.0%) patients. The lower limb was involved in 30 (83.3%) patients, who had osteoarticular injuries to the femur and leg combined with injury to the popliteal artery. Fasciotomy was performed in 11 (30.6%) patients and secondary amputation in 7 (19.4%) patients. The limb salvage rate was 80.6%. Median patient survival was 9.3 [0-74.8] months.

DISCUSSION

Coordinated work by two surgical teams is crucial to manage concomitant vascular and osteo-articular injuries. The management sequence must be defined clearly. Computed tomography angiography is the investigation of choice and should be performed at the slightest suspicion of vascular injury.

LEVEL OF EVIDENCE

IV, retrospective observational study.

Comparison of direct site endovascular repair utilizing expandable polytetrafluoroethylene stent grafts versus standard vascular shunts in a porcine (Sus scrofa) model

INTRODUCTION

The small diameter of temporary vascular shunts for vascular trauma management may restrict flow and result in ischemia or early thrombosis. We have previously reported a clinical experience with direct, open surgical reconstruction using expandable polytetrafluoroethylene stent grafts to create a "sutureless" anastomosis as an alternative to standard temporary vascular shunts. We sought to characterize patency and flow characteristics of these grafts compared with standard shunts in a survival model of porcine vascular injury.

METHODS

Twelve Yorkshire-cross swine received a 2-cm-long near-circumferential defect in the bilateral iliac arteries. A 14 Fr Argyle shunt was inserted into one randomly assigned artery, with a self-expanding expandable polytetrafluoroethylene stent deployed in the other. At 72 hours, conduit patency was evaluated by angiography. Arterial flow measurements were obtained at baseline, immediately after intervention, and after 72 hours via direct measurement with perivascular flow meters. Blood pressure proximal and distal to the conduits and arterial samples for histopathology were obtained during the terminal procedure.

RESULTS

Angiography revealed no difference in patency at 72 hours (p = 1.0). While there was no difference in baseline arterial flow between arteries (p = 0.63), the stent grafts demonstrated significantly improved blood flow compared with shunts both immediately after intervention (390 ± 36 mL/min vs. 265 ± 25 mL/min, p = 0.002) and at 72 hours (261 ± 29 mL/min vs. 170 ± 36 mL/min, p = 0.005). The pressure gradient across the shunts was greater than that of the stent grafts (11.5 mm Hg [interquartile range, 3-19 mm Hg] vs. 3 mm Hg [interquartile range, 3-5 mm Hg], p = 0.013). The speed of deployment was similar between the two devices.

CONCLUSIONS

Open "sutureless" direct site repair using commercially available stent grafts to treat vascular injury is a technically feasible strategy for damage control management of peripheral vascular injury and offers increased blood flow when compared with temporary shunts. Furthermore, stent grafts may offer improved durability to extend the window until definitive vascular repair. The combination of these traits may improve outcomes after vascular injury.

LEVEL OF EVIDENCE

Epidemiologic/Prognostic, level III.

Vascular Shunts in Civilian Trauma

Experience with temporary intravascular shunts (TIVS) for vessel injury comes from the military sector and while the indications might be clear in geographically isolated and under resourced war zones, this may be an uncommon scenario in civilian trauma. Data supporting TIVS use in civilian trauma have been extrapolated from the military literature where it demonstrated improved life and limb salvage. Few non-comparative studies from the civilian literature have also revealed similar favorable outcomes. Still, TIVS placement in civilian vascular injuries is uncommon and by some debatable given the absence of clear indications for placement, the potential for TIVS-related complications, the widespread resources for immediate and definitive vascular repair, and the need for curtailing costs and optimizing resources. This article reviews the current evidence and the role of TIVS in contemporary civilian trauma management.

Temporary arterial shunts in damage control: Experience and outcomes

BACKGROUND

Arterial shunting is a well-described method to control hemorrhage and rapidly reestablish flow, but optimal shunt dwell times remain controversial. We hypothesized that prolonged shunt dwell times of more than 6 hours are related to adverse outcomes after major arterial injury.

METHODS

A review (2005-2013) of all patients with arterial shunts placed after traumatic injury at our urban Level I trauma center was undertaken. Patients who died prior to shunt removal (n = 7) were excluded. Shunt complications were defined as dislodgement, thrombosis, and distal ischemia. Patients were compared on the basis of shunt complications with respect to clinical parameters.

RESULTS

The 42 patients who underwent arterial shunting after major vascular injury were primarily young (median, 26 years; interquartile range [IQR], 22-31 years) males (97.6%), severely injured (Injury Severity Score, 17.5 [IQR, 14-29]; shunted vessel Abbreviated Injury Scale score, 4 [IQR, 3-4]) by gunshot (85.7%) requiring neck/torso (33.3%) or upper-extremity (19.1%) or lower-extremity (47.6%) shunts. Thirty-five patients survived until shunt removal, and 5 (14.3%) of 35 developed shunt complications. Demographics and clinical characteristics were compared between those with shunt dwell times of less than 6 hours (n = 19) and more than 6 hours (n = 16). While patients appeared to have a greater injury burden overall in the group with dwell times of more than 6 hours, there were no statistical differences between groups with respect to age, gender, initial systolic blood pressure or hemodynamics during the shunt dwell period, use of vasopressors, Abbreviated Injury Scale score of the shunted vessel, Injury Severity Score, or outcomes including limb amputation or mortality. No patients (0/19) with shunt dwell times of less than 6 hours developed complications, whereas 5 (31.3%) of 16 patients with dwell times of more than 6 hours developed shunt complications (p = 0.05).

CONCLUSIONS

In this civilian series, 14% of patients with arterial shunts developed shunt complications. Our data suggest that limiting shunt dwell times to less than 6 hours when clinically feasible may decrease adverse outcomes.

LEVEL OF EVIDENCE

Therapeutic/care management study, level IV.

Randomized controlled trial comparing dynamic simulation with static simulation in trauma

BACKGROUND

Current general surgery residents have limited exposure to open trauma operative cases. Simulation supplements variable rotation volume and provides experience with critical but rarely performed procedures. Open simulation classically focuses on static models with anatomic accuracy but lacks practicality when hemorrhage control is the lifesaving maneuver. We sought to evaluate whether training on a dynamic simulator, while much less expensive than training on a static cadaver, might be at least as effective in training surgery residents to expeditiously place temporary vascular shunts (TVSs).

METHODS

Our research team developed an inexpensive, reusable dynamic simulator with ongoing hemorrhage to instruct trainees in the steps of TVS placement. We enrolled 54 general surgery residents in a noninferiority randomized controlled trial comparing training of TVS placement on the dynamic simulator (n = 28) versus a cadaver arm (n = 26). After standardized video didactics, trainees practiced on either the simulator or cadaver arm. After the trainees achieved competency, they were tested on placing a TVS for a live swine femoral artery injury. Two blinded trauma surgeons evaluated the recorded performances.

RESULTS

Residents did not differ in baseline characteristics between groups, and all residents in both groups successfully completed the TVS placement test. Subjects trained on the simulator placed the TVS faster than those trained on a cadaver (584 seconds vs. 751 seconds; difference, +167 seconds faster; 90% confidence interval [CI], +52 to +282 seconds), with a trend toward faster time to hemorrhage control (110 seconds vs. 148 seconds; difference, +38 seconds faster; 90% CI, -8 to +84). There was no significant difference in Objective Structured Assessment of Technical Skills scores (3.72 vs. 3.44; difference, +0.27 units better; 90% CI, -0.04 to +0.59).

CONCLUSION

Training on a dynamic simulator resulted in noninferior time to completion of vascular shunt placement compared with training on a cadaver. The addition of dynamic hemorrhage to simulators might inexpensively augment trauma skills training.

What's new in operative trauma surgery in the last 10 years

PURPOSE OF REVIEW

This article reviews the latest operative trauma surgery techniques and strategies, which have been published in the last 10 years. Many of the articles we reviewed come directly from combat surgery experience and may be also applied to the severely injured civilian trauma patient and in the context of terrorist attacks on civilian populations.

RECENT FINDINGS

We reviewed the most important innovations in operative trauma surgery; the use of ultrasound and computed tomography in the preoperative evaluation of the penetrating trauma patient, the use of temporary vascular shunts, the current management of military wounds, the use of preperitoneal packing in pelvic fractures and the management of the multiple traumatic amputation patient.

SUMMARY

The last 10 years of conflict has produced a wealth of experience and novel techniques in operative trauma surgery. The articles we review here are essential for the contemporary care of the severely injured trauma patient, whether they are card for in a level 1 trauma center or in a field hospital at the edge of a battlefield.

Prophylactic fasciotomy in a porcine model of extremity trauma

BACKGROUND

Extremity injury, with concomitant hemorrhagic shock, can result in ischemia-reperfusion injury and the formation of compartment syndrome requiring fasciotomy. As the benefit of prophylactic fasciotomy is unclear, the objective of this study is to determine the functional recovery of an ischemic limb with hemorrhagic shock after prophylactic fasciotomy.

MATERIAL AND METHODS

Yorkshire swine underwent 35% blood volume hemorrhage, followed by 1, 3, and 6 h of ischemia (n = 17; 1HR, 3HR, and 6HR) via iliac artery occlusion followed by repair and reperfusion. A second cohort (n = 18) underwent fasciotomy of the anterior compartment of the hind limb following vascular repair (1HR-F, 3HR-F, and 6HR-F). Compartment pressures, measures of electromyographic (EMG) recovery, and a validated gait score (modified Tarlov) were performed throughout a 14-d survival period.

RESULTS

Increasing ischemic intervals resulted in incremental increases in compartment pressure (P < 0.05), although the mean did not exceed 30 mm Hg. EMG studies did not show a significant improvement comparing the 3HR with 6HR groups. There was a significant improvement in the EMG studies within the 3HR-F, when compared with 6HR-F. There was a trend toward sensory improvement between the 3HR-F and 3HR groups. However, this did not translate to a difference in functional outcome as measured by the Tarlov gait score.

CONCLUSIONS

Within this swine model of hemorrhagic shock and hind limb ischemia, the use of prophylactic fasciotomies did not improve functional outcome.

Damage control strategies in the management of acute injury

Traumatic injury is the leading cause of death worldwide. The rapid evaluation and correction of injuries in these patients is paramount to preventing uncontrolled decompensation and death. Damage control strategies are a compendium of techniques refined over decades of surgical care that focus on the rapid correction of deranged physiology, control of contamination and blood loss, and resuscitation of critical patients. Damage control resuscitation (DCR) focuses on the replacement of lost blood volume in a manner mimicking whole blood, control of crystalloid administration, and permissive hypotension. Damage control laparotomy controls gastrointestinal contamination and bleeding in the operative suite, allowing rapid egress to the intensive care unit for ongoing resuscitation. Pelvic packing, an adjunct to DCR, provides a means to control hemorrhage from severe pelvic fractures. Temporary vascular shunts restore perfusion, while resuscitation and reconstruction are ongoing. Taken together, these strategies provide the trauma surgeon with a powerful arsenal to preserve life in the transition from injury to the shock trauma room to the intensive care unit.

Evaluation and management of penetrating lower extremity arterial trauma: an Eastern Association for the Surgery of Trauma practice management guideline

BACKGROUND

Extremity arterial injury after penetrating trauma is common in military conflict or urban trauma centers. Most peripheral arterial injuries occur in the femoral and popliteal vessels of the lower extremity. The Eastern Association for the Surgery of Trauma first published practice management guidelines for the evaluation and treatment of penetrating lower extremity arterial trauma in 2002. Since that time, there have been advancements in the management of penetrating lower extremity arterial trauma. As a result, the Practice Management Guidelines Committee set out to develop updated guidelines.

METHODS

A MEDLINE computer search was performed using PubMed (www.pubmed.gov). The search retrieved English language articles regarding penetrating lower extremity trauma from 1998 to 2011. References of these articles were also used to locate articles not identified through the MEDLINE search. Letters to the editor, case reports, book chapters, and review articles were excluded. The topics investigated were prehospital management, diagnostic evaluation, use of imaging technology, the role of temporary intravascular shunts, use of tourniquets, and the role of endovascular intervention.

RESULTS

Forty-three articles were identified. From this group, 20 articles were selected to construct the guidelines.

CONCLUSION

There have been changes in practice since the publication of the previous guidelines in 2002. Expedited triage of patients is possible with physical examination and/or the measurement of ankle-brachial indices. Computed tomographic angiography has become the diagnostic study of choice when imaging is required. Tourniquets and intravascular shunts have emerged as adjuncts in the treatment of penetrating lower extremity arterial trauma. The role of endovascular intervention warrants further investigation.

Simple posterior elbow dislocation and brachial artery transection

We report the uncommon occurrence of a complete brachial artery transection following simple posterior dislocation of the elbow, successfully managed by cephalic vein interposition grafting. This case together with a review of the literature was conducted with the aim of highlighting important issues regarding the diagnosis, management and prognosis of this rare complication.