From the Guidelines
To diagnose compartment syndrome, measuring compartment pressures using a pressure monitor device is the best test, with diagnosis confirmed when absolute pressures exceed 30 mmHg or when the delta pressure (diastolic blood pressure minus compartment pressure) is less than 30 mmHg. This approach is supported by the most recent and highest quality study, which emphasizes the importance of early diagnosis and treatment to prevent permanent tissue damage 1.
Clinical Examination
Before measuring pressures, a thorough clinical examination should be performed, looking for the classic signs of compartment syndrome, including:
- Pain out of proportion to injury
- Pain on passive stretch
- Paresthesia
- Pallor
- Paralysis
- Pulselessness (though pulses may remain present until late) However, these clinical signs have a low sensitivity for the diagnosis of compartment syndrome, but a high negative predictive value 1.
Pressure Measurements
Pressure measurements are particularly important when clinical assessment is limited, such as in unconscious patients or those with altered mental status. Normal compartment pressures are below 10-12 mmHg, and compartment syndrome is diagnosed when absolute pressures exceed 30 mmHg or when the delta pressure (diastolic blood pressure minus compartment pressure) is less than 30 mmHg 1.
Importance of Early Diagnosis
Early diagnosis is critical as compartment syndrome is a surgical emergency requiring immediate fasciotomy to prevent permanent tissue damage, which can occur within 6-8 hours of onset. The benefits of fasciotomy decrease, and the disadvantages increase considerably the later fasciotomy is performed 2.
Risk Factors
Patients with severe limb(s) trauma presenting with risk factors such as fracture, crush injury, haemorrhagic injury or reperfusion of an ischaemic lesion, and hypotension should be investigated repetitively (every 30 min to 1 h), during the first 24 h, for the presence of clinical signs of compartment syndrome 1.
From the Research
Diagnosis of Compartment Syndrome
The diagnosis of compartment syndrome is a critical aspect of its management, as delayed diagnosis can lead to irreversible damage. The following are the key points to consider:
- Compartment syndrome is defined as an increased intracompartmental pressure within inelastic fascia that surround muscular compartments 3.
- The diagnosis of compartment syndrome is made on the basis of physical examination and repeated intracompartmental pressure (ICP) measures 4.
- ICP higher than 30 mmHg of diastolic blood pressure is significant of compartment syndrome 4.
- Measurement of intracompartmental pressures using a pressure monitor is the most reliable test for diagnosing compartment syndrome 5.
- History and physical examination are typically unreliable and cannot rule out the diagnosis of compartment syndrome 5.
Intracompartmental Pressure Measurement
Intracompartmental pressure measurement is a crucial aspect of diagnosing compartment syndrome. The following are the key points to consider:
- Intracompartmental pressure measurement is the gold standard for diagnosing compartment syndrome 6.
- A pressure of 30 mmHg is considered the critical threshold for diagnosing compartment syndrome 3, 4.
- Pressure measurements should be systematically produced to confirm the presence of compartment syndrome and define optimal surgical strategies 7.
Clinical Presentation
The clinical presentation of compartment syndrome can vary, but the following are the key points to consider:
- Pain is typically the earliest finding in patients with compartment syndrome 5.
- Other symptoms of compartment syndrome include paresthesias, pain with passive stretch, tenseness or firmness of the compartment, focal motor or sensory deficits, or decreased pulse or capillary refill time 5.
- Compartment syndrome can present with a variety of findings, making it essential to consider it in the differential diagnosis of patients with trauma or fractures 5.