Management of the Mangled Extremity
Although a precise definition remains elusive, any extremity sustaining sufficiently severe injury to a combination of vascular, bony, soft tissue and/or nerve structures that results in subsequent concern for viability of the limb should be considered a mangled extremity and evaluated appropriately to optimize the potential for functional outcome. Figure 1 and the supporting text comprise an algorithm for making decisions in the management of adult patients who sustain a mangled extremity. In the absence of prospective randomized trials, this algorithm is based on expert opinion and published observational studies. We recognize that variability in decision making will continue based on local resources and local expert consensus opinion. The algorithm and accompanying text are designed to address mangled extremities seen in civilian practice. We recognize military injuries will differ and may require different strategies. Some but not all the principles in this document may be relevant for some battlefield injuries.
The algorithm contains letters A through K, which correspond to lettered text. This text is intentionally concise and its purpose is to navigate the reader through the algorithm and to identify and discuss the gray zones in the logic of this decision making. The annotated algorithm is intended to (a) serve as a quick reference for bedside clinicians, (b) foster more detailed local patient care protocols that will allow for prospective collection of data to identify best practices, and (c) generate research projects to answer specific questions concerning decision making.
It is important to note that our presented algorithm is designed to provide guidance only on the evaluation and treatment of the mangled extremity beginning in the emergency department, and that the prehospital management of these injuries is beyond the scope of this offering. Where possible, known risk factors for adverse outcome have been listed for incorporation in the management decision (Table 1). All listed risk factors are those that have been previously elucidated from the studies available for review. Additional risk factors may also be of undefined importance, including diabetes, antecedent peripheral vascular disease, obesity, and hypercoagulability. Finally, the great majority of data available on mangled extremities has focused on evaluation and treatment of lower limbs with comparatively less described regarding upper extremities. We recognize that loss of an upper extremity, particularly a dominant upper extremity results in a more severe functional loss then a lower extremity. Emotionally, loss of an upper extremity may be much more difficult than a lower extremity. Thus, more aggressive attempts at limb salvage may be appropriate. However, for the sake of our present algorithm, we do not distinguish between the upper and lower extremities, recognizing that most of the general principles discussed have similar applications regardless of extremity location.
The issues addressed in this management algorithm are diagnostic evaluation, indications for emergent amputation, and critical decisions regarding the viability of the limb and potential for limb salvage. Mangled extremities almost by definition involve Gustilo type III B or III C injuries (Table 3). Many of these determinations will be greatly influenced by the availability of resources, the expertise available, and factors that may well vary from institution to institution. It is important to stress that the initial evaluation of a patient with a mangled extremity does not differ from that of any other patients with multiple injuries. The initial ABC’s of evaluation take precedence. Providers must resist the temptation to become diverted by the graphic appearance of the extremity and maintain a systematic approach that focuses on the detection and effective treatment of more serious issues. The only immediately life-threatening aspect of the extremity is external blood loss. An ischemic limb does not represent an immediate threat to life. It is a common pitfall, among inexperienced providers, to reach for the Doppler probe in an effort to assess distal perfusion as a component of the primary survey. This practice may result in the delayed diagnosis of truncal hemorrhage, brain injury, or other immediately lifethreatening conditions. Without an algorithmic approach to the mangled extremity, errors in management may occur. Typical errors that might occur include failure to accomplish timely reperfusion of ischemic tissue, delays associated with ineffective communication between senior surgeons from the necessary specialties, unnecessary delays because of inappropriate vascular imaging requests, inadequate debridement and fracture stabilization, and delays in soft tissue coverage attempts.