Approach Considerations
The treatment of choice for acute compartment syndrome is early decompression. If the tissue pressure remains elevated in a patient with any other signs or symptoms of a compartment syndrome, adequate decompressive fasciotomy must be performed as an emergency procedure. Following fasciotomy, fracture reduction or stabilization and vascular repair can be performed, if needed.
If a developing compartment syndrome is suspected, place the affected limb or limbs at the level of the heart. Elevation is contraindicated because it decreases arterial flow and narrows the arterial-venous pressure gradient. [13, 14]
In patients with tibial fracture and suspected compartment syndrome, immobilize the lower leg with the ankle in slight plantar flexion, which decreases the deep posterior compartment pressure and does not increase the anterior compartment pressure. (Postoperatively, the ankle is held at 90° to prevent equinus deformity.)
All bandages and casts must be removed. Releasing 1 side of a plaster cast can reduce compartment pressure by 30%, bivalving can produce an additional 35% reduction, [60] and complete removal of the cast reduces the pressure by another 15%, for a total decrease of 85% from baseline. [67] Cutting undercast padding (Webril, Kendall Healthcare Products Co) may decrease compartmental pressure by 10-30%. [68, 60, 10]
Administer antivenin in cases of snake envenomation; this may reverse a developing compartment syndrome. Correct hypoperfusion with crystalloid solution and blood products.
Relative hypertension and correction of acute anemia may help prevent the development of an impending acute compartment syndrome. Ongoing research continues to examine the role of nitric oxide.
In the setting of an acute compartment syndrome, capillary permeability is altered after 3 hours, resulting in postischemia tissue swelling of 30-60%. The role of mannitol in decreasing tissue edema is still under investigation; it may reduce compartment pressures and lessen reperfusion injury. [69, 70, 71] Vasodilator drugs or sympathetic blocking drugs appear to be ineffective, probably because maximal local vasodilatation is already present in this condition.
Observation
A retrospective British study indicated that children under age 12 years with a minimally displaced tibial fracture can be safely treated and discharged without inpatient observation for acute compartment syndrome. Malhotra et al reviewed the clinical and radiographic progress of 159 tibial fractures (81% in the diaphyseal region) in patients under 12 years; in 60% of the injuries, the tibia alone was involved. Most of the 159 fractures (66%) were treated nonoperatively. None of the patients in the study developed acute compartment syndrome. [72]
Based on the study, Malhotra and colleagues advised that children under 12 years with a minimally displaced, tibia-only fracture can be placed in a back-slab cast and discharged from the emergency department with early follow-up, as long as their pain is being effectively addressed and they can mobilize under their parents’ supervision. Inpatient observation for acute compartment syndrome may be advisable, according to the investigators, in patients who have suffered a high-energy injury, who have a displaced fracture, or who also have a fibular fracture. [72]
Renal Protection
Ischemia that lasts 4 hours leads to significant myoglobinuria, which reaches a maximum about 3 hours after the circulation is restored but persists for as long as 12 hours. In the face of rhabdomyolysis, IV fluid administration and, potentially, bicarbonate may be used to keep urine output at 1-2 mL/kg/hr.
The combination of hypovolemia, acidemia, and myoglobinemia may cause acute renal failure. Alkalization of the urine and diuresis appear to be renal-protective, presumably because hemoglobin and myoglobin are more soluble in an alkaline solution. Patients who survive almost always recover renal function, even those patients who require prolonged hemodialysis. Current recommendations are as follows:
-
Correct hypovolemia with crystalloid solution
-
Infuse 500 mL/hr of crystalloid solution and 22.4 mEq bicarbonate (12 L/day, forcing diuresis of approximately 8 L/day)
-
If diuresis is less than 300 mL/hr, administer mannitol dose of 1 g/kg
-
If blood pH is greater than 7.45, administer 250 mg acetazolamide
-
Monitor vital signs and urine pH level and volume hourly
-
Assess osmolarity and electrolytes and arterial blood gas every 6 hours
Indications for Fasciotomy
The definitive surgical therapy for compartment syndrome is emergent fasciotomy to release the involved compartment, with subsequent fracture reduction or stabilization and vascular repair, if needed. When compartment pressures are elevated, especially in acute settings, prompt surgical evaluation should be performed, since elevated pressures can, over a prolonged period, cause irreversible damage. [73, 74] However, no consensus exists regarding the exact pressure at which fasciotomy should be performed. [17, 19, 21, 22, 75, 76, 77]
Whitesides et al advised that fasciotomy should be performed when the compartment pressure rises to within 10-30 mm Hg of the patient's diastolic blood pressure (the so-called delta-P). [78, 79] McQueen and Court-Brown, studying compartment syndrome in dogs, affirmed the difference of 30 mm Hg between the compartment pressure and the diastolic blood pressure as a more reliable measure than absolute pressure measurements. [53]
Currently, many surgeons use a measured compartment pressure of 30 mm Hg as a cutoff for fasciotomy. Multiple pressure readings are often obtained, and the clinician must decide how to incorporate these readings with the clinical picture in the decision-making process.
Mubarak and Hargens recommended that fasciotomy be performed for the following patients [29] :
-
Those who are normotensive with positive clinical findings, who have compartment pressures of greater than 30 mm Hg, and whose duration of increased pressure is unknown or thought to be longer than 8 hours
-
Those who are uncooperative or unconscious, with a compartment pressure of greater than 30 mm Hg
-
Those with low blood pressure and a compartment pressure of greater than 20 mm Hg
The tolerance of tissue to prolonged ischemia varies depending on the type of tissue that is involved. Matsen showed that muscles have functional impairment after 2-4 hours of ischemia and irreversible functional loss after 4-12 hours. [11]
Nerve tissue shows abnormal function after 30 minutes of ischemia, with irreversible functional loss after 12-24 hours. Additional experimental data, however, have shown significant changes in somatosensory potentials as early as 45 minutes after compartment pressure increases up to 30 mm Hg.
If the compartment pressure is greater than 40 mm Hg, a fasciotomy is usually performed emergently, and fasciotomy is indicated if the pressure remains 30-40 mm Hg for longer than 4 hours. As a rule, when in doubt, the compartment should be released.
In a study of patients with clinical signs of compartment syndrome after revascularization surgery for lower limb ischemia, Arato et al reported that measurement of intracompartmental pressure and tissue oxygenation (measured with near-infrared spectroscopy) could be used to determine whether fasciotomy was needed. [80] Patients with pressure below 40 mm Hg and normal tissue oxygen saturation were treated conservatively.
With compartment syndrome in the hand, surgeons should have a lower threshold for decompression; a compartmental pressure of greater than 15-20 mm Hg is a relative indication for release.
If compartment syndrome is diagnosed late, fasciotomy is of no benefit. In fact, fasciotomy probably is contraindicated after the third or fourth day following the onset of compartment syndrome.
When fasciotomy is performed late, severe infection usually develops in the necrotic muscle. However, if the necrotic muscle is left alone and the compartment is not open, it can heal with scar tissue. This may result in a more functional extremity with fewer complications. However, if the duration of compartment syndrome is unclear, the surgeon should elect to decompress the indicated compartments.
A study by Blair et al found that in patients with tibial fractures, four-compartment fasciotomy for acute compartment syndrome is associated with an increased likelihood of infection and nonunion. The study included patients with tibial plateau or shaft fractures with acute compartment syndrome (46 patients) or without acute compartment syndrome (138 patients), with the compartment syndrome patients receiving two-incision four-compartment fasciotomy. Nonunion and deep infection both occurred at a rate of 20% in the compartment syndrome/fasciotomy patients, versus 5% and 4%, respectively, in the other patients. [81]
In the setting of a vascular injury, a fasciotomy should be performed on high-risk patients before arterial exploration. High-risk patients include those with prolonged ischemia time, significant preoperative hypotension, associated crush injury, combined arterial and venous injury, or the need for a major venous ligation in the popliteal or femoral area.
In a survey by Collinge et al of Orthopaedic Trauma Association members, there was a consensus among respondents that wound closure or skin grafting should occur within 1-5 days postfasciotomy. Respondents universally recommended that skin grafting be employed if more than 7 days elapsed before closure. [82]
Compartment Syndrome After Arthroscopy
Studies by Nillius and Rooser, Peek and Haynes, and Fruensgaard and Holm documented the incidence of compartment syndrome following knee arthroscopy and evaluated fasciotomies as treatment. [83, 84, 85] However, Kaper et al have suggested that emergency fasciotomies are not absolutely indicated. [86] Rather, observation of the patient in the recovery room, with serial examinations and repeat compartment pressure measurements, may be considered.
Pressure measurements of the contralateral extremity may be useful as a control to verify the accuracy of the readings. If persistently elevated pressures are recorded or the development of clinical findings consistent with compartment syndrome are noted, the patient can still be returned to the operating room within the 6 hours prior to development of irreversible myonecrosis.
Hyperbaric Oxygen Therapy
The Hyperbaric Oxygen (HBO) Committee of the Undersea and Hyperbaric Medical Society (UHMS) reported 13 major syndromes amenable to HBO, of which fourth on the list is crush injury, compartment syndrome, and other acute traumatic ischemias. [87] HBO promotes hyperoxic vasoconstriction, which reduces swelling and edema and improves local blood flow and oxygenation. It also increases tissue oxygen tensions and improves the survival of marginally viable tissue. [88]
At the time of surgical debridement, prior treatment with HBO aids in the demarcation of nonviable tissue. The best results are obtained when therapy is started early. Twice-daily treatments at 2.0 atmosphere absolute (ATA) to 2.5 ATA for 90-120 minutes are recommended for 5-7 days, with frequent examinations of the affected area. Despite the recommendation for HBO, most authors strongly advise caution in employing this modality. The treatment of choice for compartment syndrome is early decompression.
Physical Therapy and Occupational Therapy
The patient who undergoes fasciotomy requires a physical therapy program to regain function. Postoperative care and rehabilitation are just as important as the procedure itself.
During the immediate postoperative period, weight bearing is limited, and assistive devices (eg, crutches) are needed. Within a few days and with adequate pain control, the use of crutches can be discontinued. The rehabilitation program then involves range of motion (ROM) and flexibility exercises involving the muscles of the affected compartment. Adjacent joints need to be exercised to maintain their normal ROM.
Once the patient is able to ambulate with a normalized gait pattern, a program of graduated resistive exercises (depending on the person's regular activities or work) is initiated. In the case of athletes, sports-specific exercises are started with the intention of returning to a regular athletic schedule. Cross training is also beneficial for these athletes. Activities such as swimming, pedal exercises, water jogging, and running help athletes regain muscle strength and flexibility without loading the affected compartment.
With surgical intervention for decompression, occupational therapy consultation should be considered early in the postoperative period for assessment of appropriate treatment and of the patient's deficits with regard to activities of daily living (ADL). Therapy for ADL as well as instruction in the use of any necessary assistive device(s) may be indicated.
Complications
With late diagnosis, irreversible tissue ischemia can develop in the acute setting. Thus, permanent muscle and nerve damage, along with chronic pain, may occur. Peroneal nerve palsy, in particular, may develop. With muscle damage, muscle contractures may be observed. For more information on management of contractures, see the Medscape Reference article Volkmann Contracture.
Hypesthesia and painful dysesthesia can also result from compartment syndrome. These may resolve slowly with time. Phenytoin (Dilantin), gabapentin (Neurontin), or carbamazepine (Tegretol) may be of some value in making the patient more comfortable.
-
(Click Image to enlarge.) Volar release in the forearm. The upper illustration shows the incision that is used. The lower left picture depicts the relevant incisional anatomy. The lower right picture depicts the cross-sectional anatomy.
-
Surgical anatomy of the volar forearm. Photo courtesy of Dr. Smith, Harborview/UW Medical Center, Department of Orthopaedics, Seattle, Wash.
-
(Click Image to enlarge.) Two-incision anterolateral fasciotomy. Photographs courtesy of DG Smith, MD, Harborview Hospital, Seattle, WA.
-
(Click Image to enlarge.) Two-incision posteromedial fasciotomy. Photographs courtesy of DG Smith, MD, Department of Orthopedics, Harborview Hospital, Seattle, WA.
-
(Click Image to enlarge.) Single-incision fasciotomy. Photographs courtesy of DG Smith, MD, Harborview Hospital, Seattle, WA.
-
Picture of compartment pressure measuring device for use when commercial devices are unavailable.
-
Stryker STIC Monitor. Image courtesy of Stryker Corporation, used with permission.
