Heroic procedures in vascular injury management: the role of extra-anatomic bypasses

Update in combined musculoskeletal and vascular injuries of the extremities

Combined musculoskeletal and vascular injuries of the extremities are conditions in which a multidisciplinary approach is a sine qua non to ensure life initially and limb viability secondarily. Vascular injuries as part of musculoskeletal trauma are usually the result of the release of a high energy load in the wound site so that the prognosis is determined by the degree of soft-tissue damage, duration of limb ischemia, patient's medical status and presence of associated injuries. The management of these injuries is challenging and requires a specific algorithm of action, because they are usually characterized by increased morbidity, amputation rate, infection, neurological and functional deficits, and they could be life threatening. Although vascular injuries are rare and occur either isolated or in the context of major combined musculoskeletal trauma, the high index of suspicion, imaging control, and timely referral of the patient to organized trauma centers ensure the best functional outcome of the extremity in such challenging cases. Even after a successful initial treatment of a combined trauma pattern, long-term follow-up is crucial to prevent and detect early possible complications. The purpose of this manuscript is to provide an update on diagnosis and treatment of combined musculoskeletal and vascular injuries of the extremities, from an orthopedic point of view.

For the patient-Evolution in the management of vascular trauma

There has been an evolution in the diagnosis and management of vascular trauma over the past 100 years. The primary stimulus to these changes has been the increased volume of patients with cervical, truncal, and peripheral vascular injuries during military conflicts and in civilian life. Patients with "hard" signs of a vascular injury are taken to surgery emergently with a few exceptions to be described. In contrast, patients with "soft" signs of a vascular injury undergo a careful physical examination including measurement of vascular index to determine if radiologic imaging is necessary. Computed tomography arteriography has become the most commonly used method of imaging, whereas duplex ultrasonography is used in some centers. Nonoperative management is now common for nonocclusive injuries diagnosed on computed tomography arteriography. Proximal tourniquets are commonly used to control exsanguinating hemorrhage from injuries to extremities, whereas balloons can be used to control hemorrhage from difficult to expose areas at operation. Temporary intraluminal shunts are now used in 3% to 9% of arterial injuries. Operative techniques of repair have been refined and contribute to the excellent results noted in modern trauma centers.

Pitfalls in the management of peripheral vascular injuries

Over the past 65+ years, most civilian peripheral vascular injuries have been managed by trauma surgeons with training or experience in vascular repair or ligation. This is appropriate as the in-hospital trauma team is immediately available, and there are often other injuries present in the victim.

The pitfall to avoid during evaluation of the patient in the emergency center is a missed diagnosis. In the patient without ‘hard’ signs of a peripheral vascular injury, a careful history (bleeding), physical examination including measurement of ankle–brachial (ABI) or brachial–brachial index and liberal use of CT arteriography depending on an ABI <0.9 should essentially make the diagnosis if an arterial injury is present.

At operation, one pitfall is to limit skin preparation and draping, thereby eliminating the option of removing the greater saphenous vein if needed as a conduit from either the groin or ankle of an uninjured lower extremity. Another pitfall is to make a full longitudinal incision directly over a large pulsatile hematoma. Rather, separate shorter longitudinal incisions should be made to obtain proximal and distal vascular control before entering the hematoma. The failure to recognize patients who should be managed initially with insertion of a temporary intraluminal shunt is a major pitfall as well. Not following time-proven and results-proven ‘fine techniques’ of operative repair is another major pitfall. Such techniques include the following: use of small angioaccess vascular clamps or silastic vessel loops; passage of proximal and distal Fogarty catheters; administration of regional or systemic heparin during complex repairs; an open anastomosis technique; and completion arteriography after a complex arterial repair in a lower extremity.

Avoiding pitfalls should allow for success in peripheral vascular repair, particularly since most patients are young with non-diseased vessels.

Management of Infected Aortic Prosthetic Grafts

The management of infected prosthetic grafts is one of the most challenging problems facing vascular surgeons. High mortality and morbidity rates with traditional treatment have led many surgeons to consider different and novel strategies. Diagnosis is usually straightforward, but occasionally is unclear even after extensive clinical and radiologic investigations. Although routine total graft excision for all infected aortic grafts is still favored by some vascular surgeons, most favor only partial graft excision if only the distal limb of the graft is involved. Placement of in situ autologous vein or cryopreserved grafts have gained popularity, and investigations are continuing regarding the use of in situ antibiotic and silver-coated prosthetic grafts. In this article the authors review the incidence and etiology of aortic graft infections, methods to prevent these complications, the diagnosis of infected aortic grafts, and lastly the management of these complicated cases, including total graft excision and partial and complete graft preservation.

Vascular Injury in Orthopedic Trauma

Vascular injury in orthopedic trauma is challenging. The risk to life and limb can be high, and clinical signs initially can be subtle. Recognition and management should be a critical skill for every orthopedic surgeon. There are 5 types of vascular injury: intimal injury (flaps, disruptions, or subintimal/intramural hematomas), complete wall defects with pseudoaneurysms or hemorrhage, complete transections with hemorrhage or occlusion, arteriovenous fistulas, and spasm. Intimal defects and subintimal hematomas with possible secondary occlusion are most commonly associated with blunt trauma, whereas wall defects, complete transections, and arteriovenous fistulas usually occur with penetrating trauma. Spasm can occur after either blunt or penetrating trauma to an extremity and is more common in young patients. Clinical presentation of vascular injury may not be straightforward. Physical examination can be misleading or initially unimpressive; a normal pulse examination may be present in 5% to 15% of patients with vascular injury. Detection and treatment of vascular injuries should take place within the context of the overall resuscitation of the patient according to the established principles of the Advanced Trauma Life Support (ATLS) protocols. Advances in the field, made mostly during times of war, have made limb salvage the rule rather than the exception. Teamwork, familiarity with the often subtle signs of vascular injuries, a high index of suspicion, effective communication, appropriate use of imaging modalities, sound knowledge of relevant technique, and sequence of surgical repairs are among the essential factors that will lead to a successful outcome. This article provides a comprehensive literature review on a subject that generates significant controversy and confusion among clinicians involved in the care of trauma patients. [Orthopedics. 2016; 39(4):249-259.].

Prevention and treatment of aortic graft infection

Prosthetic vascular graft infection remains one of the most challenging surgical problems for vascular surgeons. This condition is classically associated with high morbidity and mortality rates. Accurate diagnosis of a vascular graft infection can typically be made based on a thorough history and physical examination; although, infrequently, an extensive radiological evaluation is necessary to establish the clinical finding. Complete graft excision and extra-anatomic bypass grafting remains a commonly accepted surgical treatment strategy. Recent clinical data have supported other treatment modalities, including the use of in situ antibiotic-impregnated graft replacement, in situ allograft replacement and in situ autologous graft replacement. This article will review the pathobiology of aortic graft infection, as well as methods to prevent a prosthetic graft infection. Furthermore, various surgical treatment modalities of aortic graft infection will be discussed.

Temporary vascular shunts

Temporary vascular shunts have been used for nearly 100 years in patients. Originally, they were used as vascular grafts that were likely to thrombose as collaterals would hopefully develop. More recently, they have been used as a device to be replaced by a permanent vascular graft during the same operation or at a reoperation. Indications for the use of shunts are a "damage control" procedure for a peripheral or truncal vascular injury, Gustilo IIIC fracture of an extremity, need for perfusion as a complex revascularization is performed, and planned replantation of a hand, forearm, or arm. They are used in approximately 8% of vascular injuries treated in urban trauma centers in the United States and have an excellent patency rate without heparinization.

The wound healing process: an overview of the cellular and molecular mechanisms

Wound healing remains a challenging clinical problem and correct, efficient wound management is essential. Much effort has been focused on wound care with an emphasis on new therapeutic approaches and the development of technologies for acute and chronic wound management. Wound healing involves multiple cell populations, the extracellular matrix and the action of soluble mediators such as growth factors and cytokines. Although the process of healing is continuous, it may be arbitrarily divided into four phases: (i) coagulation and haemostasis; (ii) inflammation; (iii) proliferation; and (iv) wound remodelling with scar tissue formation. The correct approach to wound management may effectively influence the clinical outcome. This review discusses wound classification, the physiology of the wound healing process and the methods used in wound management.