Complications of Compartment Syndrome Testing
Compartment pressure measurement itself has minimal direct complications, but the primary risks involve technical inaccuracies leading to false readings and the potential for delayed diagnosis or unnecessary fasciotomy based on incorrect pressure values. 1
Technical Complications of Pressure Measurement
Equipment-Related Errors
The choice of needle size significantly affects accuracy—using an 18-gauge needle can overestimate compartment pressure by up to 18 mmHg compared to a slit catheter or side-ported needle. 1 This technical error can lead to unnecessary fasciotomies in patients who don't actually have compartment syndrome.
Different measurement techniques (traditional needle manometry, multiparameter monitors, or dedicated transducer-tipped monitors) can yield varying results, creating diagnostic uncertainty. 1
Diagnostic Threshold Complications
Using an absolute compartment pressure threshold of ≥30 mmHg in isolation without clinical correlation can result in fasciotomy rates as high as 29% after tibial surgery, many of which may be unnecessary. 1 This represents overtreatment based on testing alone.
Even higher thresholds (up to 45 mmHg) may still over-diagnose compartment syndrome when taken in isolation without clinical context. 1
Complications from Delayed or Missed Diagnosis
False Reassurance from Testing
Continuous compartment pressure monitoring shows little evidence of reducing missed compartment syndrome compared to serial clinical examination in alert, cooperative patients. 1 Over-reliance on monitoring equipment rather than clinical assessment can delay diagnosis.
Even the differential pressure threshold approach (diastolic BP minus compartment pressure <30 mmHg) combined with continuous monitoring may miss some cases of compartment syndrome by definition. 1
Limitations in Specific Populations
- In obtunded, confused, or uncooperative patients where clinical signs cannot be elicited, compartment pressure measurement becomes necessary but introduces risk of technical error. 1 Delayed measurement in these populations can lead to poor outcomes. 2, 3
Complications from Over-Reliance on Testing
Ignoring Clinical Context
Severe pain alone gives only approximately 25% chance of correctly diagnosing compartment syndrome, yet pressure measurements without clinical correlation are equally problematic. 2 The combination of testing and clinical signs is essential—neither alone is sufficient.
Palpation of the suspected compartment is unreliable in isolation (sensitivity 54%, specificity 76% in children), yet pressure measurement without palpation and other clinical signs also increases error rates. 1, 2
Indirect Complications from Testing Delays
Time Lost During Measurement
The time required to obtain and set up pressure monitoring equipment, perform the measurement, and interpret results can delay definitive treatment (fasciotomy) in obvious clinical cases. 4, 5
Irreversible ischemic damage may occur within 6 hours, making any delay from testing in clinically obvious cases potentially catastrophic. 4, 6
Infection Risk
- While minimal, any invasive pressure monitoring introduces a theoretical risk of introducing infection into the compartment, though this is rarely reported in the literature. 5
Critical Pitfalls to Avoid
Never rely solely on pressure measurements without clinical correlation—the absence of clinical signs is more accurate in excluding compartment syndrome than their presence is in making the diagnosis. 1
Never delay fasciotomy in clinically obvious cases (pain out of proportion, pain on passive stretch, and progressive neurological signs) to obtain pressure measurements. 2, 3
Never use pressure measurement as a substitute for clinical vigilance in obtunded patients—measure earlier rather than later in these high-risk populations. 2, 3
Recognize that no single sign or investigation is guaranteed to diagnose or exclude compartment syndrome—maintain high clinical suspicion despite normal pressure readings if clinical signs are concerning. 1