What are the guidelines for preventing and managing compartment syndrome in patients undergoing regional anesthesia?

Guidelines for Regional Anesthesia and Risk of Compartment Syndrome

Regional anesthesia techniques that result in dense blocks of long duration should be avoided in patients at risk of acute compartment syndrome (ACS), while single-shot or continuous peripheral nerve blocks using lower concentrations of local anesthetic drugs without adjuncts can be safely used with appropriate post-injury and postoperative surveillance. 1

Identification and Monitoring of At-Risk Patients

• Patients at risk of ACS should be identified on admission to hospital or at the time of surgery, and managed within agreed, multidisciplinary protocols 1
• Post-injury and postoperative ward observations should be performed at set frequencies by healthcare staff trained in the pathology and recognition of ACS 1
• The use of objective scoring charts, such as those provided by the UK's Royal College of Nursing, is recommended to maintain heightened awareness of ACS among healthcare workers 1

Diagnostic Approach for ACS

• Clinical signs alone have relatively low sensitivity and positive predictive value for diagnosing ACS, while their specificity and negative predictive value are high 1

• The presence of multiple clinical signs increases the likelihood of correct ACS diagnosis:

  • Severe pain and pain on passive stretch together have a positive predictive value of 68% 1
  • Pain, pain on passive stretch, and paralysis together have a predictive value of 93% (though paralysis is a late sign indicating likely irreversible muscle ischemia) 1

• Direct measurement of intracompartmental pressure is indicated when:

  • The diagnosis remains in doubt 1
  • The patient is obtunded, confused, or uncooperative 1
  • Serial clinical examination is not reliable 1

• Fasciotomy should be performed when tissue pressure increases to within 10-30 mmHg of the diastolic pressure in a patient with other signs or symptoms of ACS 1

Regional Anesthesia Recommendations

• All patients who have suffered trauma or undergone surgery should be offered effective analgesia 1

• Key recommendations regarding regional anesthesia in patients at risk of ACS:

  • Dense neuraxial or peripheral nerve blockade that extends significantly into the postoperative period should be avoided 1
  • Single-shot or continuous peripheral nerve blocks using lower concentrations of local anesthetic without adjuncts are not associated with delays in ACS diagnosis when appropriate surveillance is maintained 1

• Equipment for measuring intracompartmental pressure should be available on wards caring for patients at risk of ACS, with staff trained in its use 1

Special Considerations

• In children, ACS presents unique challenges as younger patients may have difficulty articulating symptoms 1

  • The "three As" approach (anxiety, agitation, analgesic requirement) has been suggested for diagnosing ACS in children 1
  • Age is an important predictor for ACS development, with children aged 12-19 years having a high prevalence after tibial fracture 1

• Patients should receive a full explanation of analgesic options and provide documented verbal consent 1

• While consensus between surgeons and anesthesiologists is ideal, the anesthesiologist has the right to offer appropriate analgesic techniques while acknowledging surgical concerns 1

Common Pitfalls and Caveats

• Relying solely on clinical signs may lead to missed or delayed diagnosis of ACS 1
• Late signs of ACS (loss of pulse, paralysis, pallor, decreased temperature) indicate significant disruption to limb vascularity and viability 1
• Using an 18-G needle for compartment pressure measurement may overestimate pressure by up to 18 mmHg compared with a slit catheter or side-ported needle 1
• Compartment syndrome can develop rapidly and severely, requiring immediate recognition and intervention to prevent tissue necrosis and permanent functional impairment 2
• The controversy regarding regional anesthesia in patients at risk of ACS stems from concerns about masking symptoms, but current evidence suggests that with appropriate monitoring protocols, certain regional techniques can be safely used 3, 4