Chapter 93: Compartment Pressure Measurement

INTRODUCTION

The ability to diagnose a compartment syndrome is a critical skill for the Emergency Physician (EP). Early identification of a compartment syndrome can enable the appropriate treatment and may facilitate limb salvage. A compartment syndrome begins when pressure within a myofascial compartment increases to the point that it results in diminished blood flow.^1,2 A compartment syndrome has been classically described in the early literature as a Volkmann ischemic contracture following vascular insufficiency in the forearm.³ A compartment syndrome is described as the 6 Ps (i.e., pain out of proportion, pallor, paralysis, paresthesias, pressure, and pulselessness).

A compartment syndrome can occur in almost any muscle group contained within a confined fascial space. Common locations include the leg, forearm, and gluteal area. There are many causes of a compartment syndrome. These include protracted muscle ischemia (e.g., necrosis from a contusion), swelling (e.g., fracture or volume overload), or a thrombus in a vessel that traverses the compartment. A compartment syndrome in the Emergency Department (ED) is most commonly associated with long bone fractures or blunt trauma.⁴ Most compartment syndromes are caused by trauma.² Approximately 58% of cases are due to fractures of the tibia or forearm.⁵ Other etiologies for a compartment syndrome include complications from a coagulopathy, dialysis, surgery, or states of obtundation (Table 93-1).^2,6-18

Identifying a compartment syndrome in a timely fashion can be challenging. The sensitivity and specificity of manual palpation to identify a compartment syndrome are 24% and 55%, respectively.¹⁹ Manual palpation has a positive predictive value of 19% and a negative predictive value of 63%.¹⁹ Manual palpation cannot be used to rule-in or rule-out a compartment syndrome.

The hallmark symptom of a compartment syndrome is persistent and progressive pain disproportionate to the underlying cause. The pain typically increases with passive motion. A common and dangerous mistake is to attribute the etiology of the patient’s pain solely to the underlying problem (e.g., fracture or trauma).^20,21 Other signs and symptoms associated with a compartment syndrome occur late in the disease course and include paresthesias of the involved nerve, paralysis of the involved muscle group, pallor of the skin, and diminished ...