Another bubbameisseh laid to rest? The relationship (or lack thereof) between peripheral nerve blockade and acute compartment syndrome following tibial fracture
David Polaner, MD, FAAP and Katheryn Del Pizzo, MD, Tricia Vecchione MD, MPH and Deepa Kattail MD MHS FAAP
Over the past few years, we’ve challenged a variety of anesthetic beliefs, really dogmas instilled in us by our founding fathers/mothers/teachers/textbooks in the Pediatric Anesthesia Article of the Day, many of which lack significant evidence for their benefit. These myths, or bubbameisas, (“old wives’ tales”) include long fasting (NPO) times for clears and breast milk before surgery, the use of cricoid pressure during rapid sequence intubation, and today, the fear of performing peripheral neural blockade in tibia fractures. Today’s PAAD1 and its accompanying editorial2 are based on ADULT data and experience but open a window to a very old and thorny issue.“ The debate over peripheral nerve blockade (PNB) for tibia fractures remains contentious in trauma centers worldwide. Anesthesiologists champion PNB due to its safety, quick administration, superior analgesia, reduced need for systemic medications—especially opioids—and potential improvement in blood flow to an injured limb. Conversely, orthopedic and trauma surgeons warn that PNB can mask early signs of acute compartment syndrome (ACS), such as disproportionate pain, thereby increasing the risk of avoidable severe, permanent damage.”2 This fear isn’t surprising. “The clinical diagnosis of ACS is characterized by the “6 P’s”: pain out of proportion, paresthesia, pallor, paralysis, poikilothermia, and pulselessness.3 Among these, pain out of proportion is believed to be the cardinal sign of impending compartment syndrome, but also not specific.” This largely holds true for pediatric patients as well, where the “3 A’s” are used for this challenging diagnosis which includes agitation, anxiety and increasing analgesic requirements (or escalating pain).4 Thus, the concern arises that blocking this pain with a PNB may mask this catastrophe.
I’ve asked Drs. David Polaner of the Seattle Children’s Hospital, Kate DelPizzo of the Hospital for Special Surgery (NY), Deepa Kattail of the Hospital for Sick Children, and Tricia Vecchione of the Johns Hopkins University, who have an extraordinary amount of expertise in this area, to write today’s PAAD. Myron Yaster MD
Editorial
Samet RE, Brookman JC, Grissom TE. Peripheral Nerve Blockade for Tibia Fractures: To Block or Not to Block? Is It Still a Question? Anesth Analg. 2025 140:1286-89. doi: 10.1213/ANE.0000000000007359. PMID: 39745879.
Original article
Kakalecik J, Satchell C, Root KT, Vasilopoulos T, Patrick MR, Talerico MT, Krupko TA, Nin O, Hagen JE. Relationship Between Perioperative Regional Anesthesia and the Risk of Missing Acute Compartment Syndrome Following Tibia Fractures. Anesth Analg. 2025 140:1290-96. doi: 10.1213/ANE.0000000000007084. PMID: 38941266.
Myron loves hyperbole and eye-catching titles to draw your attention. In today’s PAAD, maybe “laid to rest” is a bit premature. After all, one cannot prove or disprove either causality or safety based on retrospective observational data. Nevertheless, Kakalecik et al1 have provided us with some additional evidence against blind and total rejection of a valuable modality for postoperative analgesia in patients who have sustained fractures of the tibia, at least in adults (patients <18 yo were excluded). The contra-indication to neural block for postoperative analgesia following tibial trauma has been an orthopedic mantra for many years, even as many surgeons increasingly embrace regional analgesia for most other orthopedic operations. The primary concern is that of masking or delaying the diagnosis of acute compartment syndrome (ACS), which carries truly serious consequences, including loss of limb function, nerve injury, neuropraxia and even amputation. The arguments for prohibiting neural blockade are speculative and anecdotal in nature. Although there have been stronger and more logical and reasoned arguments against a blanket prohibition, the quantity and quality of those data haven’t been highly robust either. Perhaps the strongest argument is mechanistic in nature- that peripheral nerve blockade does not block ischemic pain, as any anesthesiologist who has seen an operative tourniquet used can report.5 Thus, it is critical that the development of breakthrough pain or escalating analgesic requirements should not be ignored with or without blockade, as it may be an early sign of impending compartment syndrome. A high index of suspicion and constant vigilance are key diagnostic tools for early detection. It is also important to be mindful of reports of “silent” ACS where ACS develops in the absence of pain reported by responsive, competent, sensate adult patients without nerve blocks.6
There were 791 patients in the in the study cohort of which 77% received a block; 88% of those had perineural catheters, 91% blocking both femoral and sciatic nerves. There was no significant difference in the primary outcome between groups, with the incidence of missed ACS of 0.7% in those with regional anesthesia compared to 1.7% in those without and the incidence of persistent nerve injury was very low in both groups. The block cohort consumed less than one half the cumulative opioid dose used by the opioid only cohort, but pain scores were not reported. While many of us believe that regional blockade provides superior quality analgesia, this study provides no data to say that is so, nor any data comparing the incidence or severity of untoward effects of either modality.
The investigators, who used 0.2% ropivacaine so as not to provide a dense block, define missed ACS as “a postinjury motor deficit diagnosed by the attending surgeon at the 3-month postoperative appointment”. This is, in reality, a surrogate end point, because it does not directly measure whether a block delays or obscures the diagnosis of ACS (the most common surgical argument against nerve blocks), but rather whether the ultimate outcome is different.
In an attempt to answer whether PNB delays diagnosis of ACS in pediatric patients, Vecchione and colleagues7 from 6 major academic pediatric centers recently reported on all pediatric patients who received PNB (over 31,000 blocks) and subsequently developed ACS. They reported a median time to diagnosis of 21.75hr with time to fasciotomy of 22.6hrs, which is comparable to times reported in cohorts without PNBs.8
The editorial2 accompanying the ADULT tibia fracture and PNB review notes many of these limitations, along with the additional obvious ones that (1) dense analgesia of any modality can mask the development of ACS pain and delay diagnosis, (2) the observational nature of the study might have obscured assignment of the highest risk patients to the opioid only group, and (3) that the best way forward to answer all these questions is a large scale prospective randomized trial.
Studying a phenomenon with such a low incidence has made data from prospective randomized control trials challenging to obtain, thus the ongoing controversy. In the meantime, orthopedic surgeons and anesthesiologists should work together to create evidence-based protocols focusing on risk assessment with a clear understanding of the complex and unpredictable presentation of ACS, rather than simple avoidance of PNB, for the betterment of patient care.
Do you perform PNBs for tibial fractures? Do your surgeons allow it? Send Myron (myasterster@gmail.com ) your thoughts and experiences and he will publish them in a Friday reader response.
References
1. Kakalecik J, Satchell C, Root KT, Vasilopoulos T, Patrick MR, Talerico MT, Krupko TA, Nin O, Hagen JE: Relationship Between Perioperative Regional Anesthesia and the Risk of Missing Acute Compartment Syndrome Following Tibia Fractures. Anesth Analg 2024
2. Samet RE, Brookman JC, Grissom TE: Peripheral Nerve Blockade for Tibia Fractures: To Block or Not to Block? Is It Still a Question? Anesth Analg 2025
3. Elliott KG, Johnstone AJ: Diagnosing acute compartment syndrome. J Bone Joint Surg Br 2003; 85: 625–32
4. Bae DS, Kadiyala RK, Waters PM: Acute compartment syndrome in children: contemporary diagnosis, treatment, and outcome. J Pediatr Orthop 2001; 21: 680–8
5. Kucera TJ, Boezaart AP: Regional anesthesia does not consistently block ischemic pain: two further cases and a review of the literature. Pain Med 2014; 15: 316–9
6. Badhe S, Baiju D, Elliot R, Rowles J, Calthorpe D: The 'silent' compartment syndrome. Injury 2009; 40: 220–2
7. Vecchione T, Bansal V, Shore BJ, Veneziano G, Sunder RA, Gurnaney H, Boretsky K: Acute compartment syndrome in pediatric patients with peripheral nerve blocks. Reg Anesth Pain Med 2025
8. Lin JS, Samora JB: Pediatric acute compartment syndrome: a systematic review and meta-analysis. J Pediatr Orthop B 2020; 29: 90–96