Concerns regarding “Regional anesthesia and acute compartment syndrome: principles for practice”

To the Editor The article by Dwyer et al entitled “Regional anesthesia and acute compartment syndrome: principles for practice” summarizes the most common trauma and elective orthopedic surgical procedures in adults associated with the development of acute compartment syndrome (ACS), stratifies relative ACS risk, and offers recommendations for the use of regional anesthesia (RA) in these cases. The article provides valuable information for the anesthesiologist and pain management team, emphasizing the importance of early identification of ACS. However, we disagree with the concluding statement “that regional anesthesia should be considered contraindicated” in surgeries at high risk for compartment syndrome. The author’s opinions on when RA is contraindicated is predicated on the unsubstantiated belief that RA can mask ischemic pain and delay timely diagnosis of ACS. The controversy first arose in 1996 when it was asserted that a single injection femoral nerve block masked pain from a tibia open reduction and internal fixation, which would require sciatic nerve blockade, and the subsequent development of ACS. This set the tone for the ensuing debate and publication bias whereby anesthesiologists claim a lack of evidence while surgeons assert notions without a solid evidencebased background. The pediatric community has been more outspoken with both the European and the American Societies of Regional Anesthesia acknowledging the lack of evidence supporting that RA increases the risk of ACS or leads to delay in diagnosis in children. The literature compromises of sporadic case reports describing patients who, sometimes did and sometimes did not, develop pain prior to the development of ACS when regional anesthesia was part of the pain management plan with conclusions both in support and rejection of the assertion. It is increasingly clear that the traditional teaching that pain out of proportion to injury being the hallmark of ACS is not absolute and not all ACS, regardless of the presence of RA, presents with pain. Recently, an entity of ACS termed “silent” is recognized by the development of ACS in the absence of pain. Subsequent cases have been reported. 5 These were responsive, competent, sensate patients without nerve blocks. Two separate studies, again in pediatric patients, report a 12% incidence of confirmed ACS presenting without pain in the absence of RA. 7 Currently, for medicolegal reasons, many surgeons and anesthesiologists likely avoid RA in patients at higher risk of ACS as Dwyer et al suggests. This continues to reinforce the belief that RA can mask ACS pain while posing a disservice to patients who may benefit from RA for adequate analgesia. It also indirectly may create a misdirected blame when patients undergoing surgeries considered low risk for ACS present with painless ACS in the setting of RA. We advocate that it will serve patients and clinicians better to understand the complex and unpredictable presentation of ACS complex. The traditional teaching that pain is the cornerstone of ACS diagnosis might not be accurate and will result in delayed diagnosis of ACS. Early recognition of ACS, particularly atypical presentations, is important to minimize longterm sequelae. A high index of suspicion and ubiquitous awareness by physicians and nurses of early symptoms are the most important diagnostic tools. We do not believe that simple avoidance of RA is in the best interest of all stakeholders, primarily our patients.