Opioid-Free Tonsillectomy With and Without Adenoidectomy: The Role of Regional Anesthesia in the “New Era”

Abstract

To the Editor As pediatric surgical techniques have advanced significantly, so has the field of pediatric anesthesia. Over the last decade, there has been a fundamental shift from opioid-based anesthetics to opioid-free or “multimodal analgesic” regimens that expedite early recovery. Thus, we read with great interest the excellent article by Franz et al,1 illustrating how a quality improvement initiative was able to implement large-scale opioid-sparing protocols to significantly reduce intraoperative and postoperative opioid consumption in a stand-alone pediatric clinic and ambulatory surgery facility. As highlighted by the authors, their interdisciplinary multimodal protocol not only utilized opioid-sparing medications such as dexmedetomidine and nonsteroidal anti-inflammatory drugs, but also incorporated regional anesthesia. However, the authors’ protocols and current clinical practice using regional anesthesia seem to focus primarily on techniques implemented below the head and neck. While the article clearly illustrates the importance of regional anesthesia in many pediatric surgical procedures, the multimodal protocol for one of the most common and painful pediatric otolaryngologic surgeries—namely tonsillectomy with and without adenoidectomy—was limited only to dexmedetomidine and ketorolac. Although there has been no clear evidence of increased risk of hemorrhage from the use ketorolac for pediatric tonsillectomy with and without adenoidectomy, ketorolac continues to be associated with increased bleeding risk by many pediatric surgeons and anesthesiologists.2 Changing this mindset can be challenging. Thus, it is important to consider a truly “multimodal” approach that utilizes not only different pharmacologic agents, but also regional techniques to provide opioid-sparing analgesia. Indeed, many nerve blocks of the head and neck, such as the blockade of the auricular branch of the vagus nerve or the suprazygomatic maxillary (SZM) nerve block, are infrequently utilized despite being well described for myringotomy3 and cleft palate surgery,4 respectively. For example, the SZM block has been shown to significantly reduce perioperative opioid use, decrease the median time to initial postoperative feeding, and minimize hospital length of stay.4 And yet, how often has anyone seen or used the SZM block in the management of their cleft palate patients within the United States? In fact, most pediatric anesthesiologists are reluctant to routinely utilize or even consider any head and neck regional technique as part of their analgesia management. Although factors such as manpower and resource availability are common challenges in the implementation of regional techniques in many institutions, perhaps a bigger obstacle is a lack of familiarity with the anatomical innervation of the head and neck as well as their relationship to various surgical and regional techniques. Fortunately, with improved ultrasound technology and expansion of its applications, an increasing number of anesthesiologists are applying ultrasound guidance to head and neck blocks to increase comfort, accuracy, and safety. It is well recognized that pain following tonsillectomy can be severe, whereas pain following adenoidectomy is generally milder. Anatomically, the palatine tonsils are mainly innervated by the lesser palatine branch of the maxillary nerve that passes through the pterygopalatine fossa and the tonsillar branches of the glossopharyngeal nerve.5 The innervation to the adenoids is supplied by the vagus and glossopharyngeal nerves via the pharyngeal plexus, the posterior palatine branch of the maxillary nerve, and fibers of the lingual branch of the mandibular nerve.5 Based on the described anatomy, the SZM block would provide only partial analgesia to both the palatine tonsils and adenoids. Additional blocks would be needed to cover the branches from the glossopharyngeal nerve. Most pediatric anesthesiologists therefore do not believe that the SZM block is worth performing if it does not offer complete analgesic coverage. However, we believe that sparing of the glossopharyngeal nerve in the SZM block is not a shortcoming but is actually a preferred advantage. The functional integrity of the glossopharyngeal nerve is important in maintaining airway protection.6 Unlike other techniques such as local infiltration of the tonsillar bed, the local anesthetic in the SZM block is deposited in the pterygopalatine fossa, which minimizes the likelihood of glossopharyngeal nerve involvement and therefore preserves airway protective mechanisms such as gagging. Thus, the SZM block should be given more consideration as a safe regional adjunct to multimodal opioid-sparing protocols for pediatric tonsillectomy and adenoidectomy surgeries. We recently established an enhanced recovery pathway for all cleft palate repairs at our institution utilizing the SZM block as part of the multimodal opioid-sparing protocol. This pathway has been well received by the surgeons and patients’ families due to the minimal need for perioperative opioids, quicker recovery times with earlier postoperative feeding success, and shorter hospital length of stay. Our experiences have been consistent with published results from other groups and institutions. Inspired by the efficacy and safety of the SZM blocks in our cleft palate patients, we recently offered the SZM blocks to a few high-risk pediatric patients undergoing tonsillectomy and adenoidectomy with severe obstructive sleep apnea and/or behavioral issues. Combined with multimodal analgesia, we noticed that our pediatric patients who received the SZM blocks woke up pain free and without any agitation. Their postoperative course in the hospital and at home was marked with zero postoperative opioid use, and pain was completely managed with an alternating regimen of acetaminophen and ibuprofen. While we are currently planning to conduct a randomized controlled study to evaluate the merit of the SZM block for postoperative analgesia following pediatric tonsillectomy and adenoidectomy, we believe that there are many other head and neck regional techniques that warrant being considered and incorporated into various multimodal regimens that can benefit our pediatric patients. With renewed interest and wide-ranging analgesic applications combined with increased use of ultrasound guidance and safety, we may be seeing a new era of head and neck regional anesthesia. Ban C. H. Tsui, MDStephanie Pan, MDLauren Smith, MDCarole Lin, MDDepartment of Anesthesiology, Perioperative, and Pain MedicineStanford University School of MedicinePalo Alto, California[email protected] Karthik Balakrishnan, MDDepartment of Otolaryngology-Head & NeckLucile Packard Children’s Hospital at StanfordStanford, California

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