Postoperative analgesia for the Nuss procedure
Erica Holland MD and David Polaner MD, FAAP, Seattle Children’s Hospital and University of Washington
Original article
Coppens S, Dewinter G, Hoogma DF, Raudsepp M, Vogelaerts R, Brullot L, Neyrinck A, Van Veer H, Dreelinck R, Rex S. Safety and efficacy of high thoracic epidural analgesia for chest wall surgery in young adolescents: A retrospective cohort analysis and a new standardised definition for success rate. Eur J Anaesthesiol. 2024 Dec 1;41(12):873-880. doi: 10.1097/EJA.0000000000002064. Epub 2024 Oct 3. PMID: 39363622.
The Nuss procedure, in which bars or struts are placed under the chest wall, has become the commonest operation for the correction of pectus excavatum.1 Although it can be considered “minimally invasive” from a surgical standpoint when compared to previous approaches, it is accompanied by considerable postoperative pain. When first introduced, thoracic epidural analgesia became the predominant modality for analgesia, although in most centers in the US, alternative methods, especially cryoablation, is now dominant. (See PAAD April 26,2022 https://ronlitman.substack.com/publish/posts/detail/52542173?referrer=%2Fpublish%2Fposts%3Fsearch%3Dcryo) In today’s PAAD, Coppens et al,2 from the University Hospital of Leuven, Belgium analyzed a 24-year retrospective cohort of adolescents who underwent chest wall remodeling procedures (mostly Nuss bars, but one third Ravitch procedures, the older operation in which the cartilage is stripped out of the perichondrium through an anterior chest incision) and received thoracic epidural analgesia (TEA) with local anesthetic and opioid infusions. The authors were concerned that the incidence of catastrophic adverse events was under-reported, so their primary outcome variable was the incidence of adverse events, and secondary outcome variables included quality of analgesia and need for supplemental analgesics. They found that 60 percent of the 532 patients experienced adverse events, primarily nausea (33%) and pruritus (26%), and that the adverse events they detected were all described as minor and self-limited. Other notable perioperative adverse events included vaso-vagal reactions during awake placement (5%), difficult placement (>3 attempts, 3%), Horner’s syndrome (2%) and mechanical issues (occlusion, leakage, migration and loss of catheters, 4%). No long term events were reported, but the follow-up duration was not specified. They reported an 80% success rate, with epidural failure defined as inadequate pain relief after emergence from anesthesia despite appropriate top-ups, or the need to re-site or abandon the epidural completely.
As the authors note, their cohort of roughly 500 patients is not large enough to adequately show safety with regards to these rare severe adverse events (epidural abscess or hematoma resulting in long term neurologic injury). Indeed, the Pediatric Regional Anesthesia Network (PRAN) 2018 publication of > 100,000 patients includes a prospective adolescent cohort of over three times as many thoracic epidurals (1825 cases >10 years of age) without any of these events.3 Furthermore, we have learned from the PRAN database that it is now the gold standard to perform regional anesthesia in pediatrics under general anesthesia, as this has the lowest risk compared with awake or sedated patients. As almost all the epidurals in this study were placed while the patient was awake, performing them post-induction would eliminate their large number of patients having a vaso-vagal reactions.
Their 60% occurrence of adverse events was driven largely by nausea/vomiting and pruritis, likely due to opioid-containing epidural infusions. Simply removing or replacing the opioids with another adjuvant, such as clonidine, might greatly reduce this rate of minor adverse events. The incidence of Horner’s syndrome was surprising (13 patients). A proportion of the epidurals were inserted at T5-6, possibly placing the catheter tip as high as T3 and, combined with supplemental boluses and patient controlled epidural analgesia (PCEA), may have been a cause of this problem.
As pectus repair is a common surgery with significant postoperative analgesic needs, a reliable and effective pain management strategy is needed. Despite the extremely effective analgesia produced by a thoracic epidural, it has largely gone out of favor in many institutions performing the Nuss procedure. While this sweeping change of practice was partly triggered by a devastating complication coming out of Dr. Nuss’s own hospital, as well as the 2012 publication of 4 severe neurologic injuries associated with epidural analgesia,4 it ultimately created an analgesia void allowing intercostal nerve cryoablation space to grow.5 Cryoablation uses precisely controlled subzero temperatures to selectively cause axonal injury resulting in downstream degeneration. However, because the perineural structures are preserved, axonal regeneration has been shown to occur, with the full postoperative return of nerve function by 1-4 months. The big concern is the risk that the nerve either doesn’t regenerate, or results in neuropathic pain. A small retrospective 2024 study by Eldredge et al.6 in the Journal of Pediatric Surgery examining the loss and return of sensory changes after pectus repair with cryoablation therapy found that chronic neuropathic pain is uncommon (6% at 6 months) and, that almost 60% of patients had full return of sensation by 6 months. The remaining sensory deficits were small, and in a pattern which made it unclear to as whether they were secondary to the cryoablation or the surgery itself. One disadvantage to an epidural is that, obviously the pain relief is gone when the catheter is pulled and the local anesthetic has worn off. Additionally, the patient must be monitored in the hospital while the catheter is in place. Both issues can be addressed with the use of cryoablation. Although high quality, large “n” studies are lacking, the data to date suggest that significant reductions in length of stay and overall costs, reduced need for systemic analgesics and prolonged analgesia can be realized with cryoablation as compared to TEA.7
So, if you preform Nuss procedures at your hospital, what are you doing for analgesia? Cryoablation? Peripheral blocks? Epidurals? If you are placing epidurals, do you use opioids in your infusion? Send your thoughts and comments to Myron who will post in a Friday reader response.
References:
1. Kelly RE, Goretsky MJ, Obermeyer R, et al. Twenty-one years of experience with minimally invasive repair of pectus excavatum by the Nuss procedure in 1215 patients. Annals of surgery 2010;252(6):1072-81. (In eng). DOI: 10.1097/SLA.0b013e3181effdce.
2. Coppens S, Dewinter G, Hoogma DF, et al. Safety and efficacy of high thoracic epidural analgesia for chest wall surgery in young adolescents: A retrospective cohort analysis and a new standardised definition for success rate. European journal of anaesthesiology 2024;41(12):873-880. (In eng). DOI: 10.1097/eja.0000000000002064.
3. Walker BJ, Long JB, Sathyamoorthy M, et al. Complications in Pediatric Regional Anesthesia: An Analysis of More than 100,000 Blocks from the Pediatric Regional Anesthesia Network. Anesthesiology 2018;129(4):721-732. (In eng). DOI: 10.1097/aln.0000000000002372.
4. Meyer MJ, Krane EJ, Goldschneider KR, Klein NJ. Case report: neurological complications associated with epidural analgesia in children: a report of 4 cases of ambiguous etiologies. Anesthesia and analgesia 2012;115(6):1365-70. (In eng). DOI: 10.1213/ANE.0b013e31826918b6.
5. Daemen JHT, de Loos ER, Vissers YLJ, Bakens M, Maessen JG, Hulsewé KWE. Intercostal nerve cryoablation versus thoracic epidural for postoperative analgesia following pectus excavatum repair: a systematic review and meta-analysis. Interact Cardiovasc Thorac Surg 2020;31(4):486-498. (In eng). DOI: 10.1093/icvts/ivaa151.
6. Eldredge RS, Lai K, Ochoa B, et al. A Prospective Study of Sensory Changes in Pediatric Patients After Minimally Invasive Repair of Pectus Excavatum With Cryoablation. J Pediatr Surg 2024;59(1):138-145. (In eng). DOI: 10.1016/j.jpedsurg.2023.09.016.
7. Lai K, Notrica DM, McMahon LE, et al. Cryoablation in 350 Nuss Procedures: Evolution of Hospital Length of Stay and Opioid Use. J Pediatr Surg 2023;58(8):1435-1439. (In eng). DOI: 10.1016/j.jpedsurg.2022.10.051.