Pediatric autologous ear reconstruction for congenital microtia requires harvesting costal cartilage from the chest wall, which causes substantial donor-site pain. To address this postoperative challenge, clinicians increasingly utilize the ultrasound-guided serratus anterior plane block. Recent evidence from a comprehensive systematic review and meta-analysis indicates that this regional technique provides predictable analgesia and minimizes opioid exposure in pediatric patients.

Costal Cartilage Harvest and Donor-Site Morbidity

Autologous auricular reconstruction remains the primary surgical technique for restoring external ear anatomy in microtia patients. During this reconstructive procedure, surgeons harvest chondral tissue from the sixth, seventh, and eighth ribs to sculpt a three-dimensional framework. Consequently, patients experience intense postoperative pain localized to the thoracic donor site rather than the newly formed ear. This severe discomfort stems from surgical perichondrial stripping, intercostal muscle trauma, and acute nerve irritation along the chest wall.

Furthermore, donor-site pain significantly limits chest wall excursion in young children. Inadequate pain management often causes voluntary splinting, shallow tidal volumes, and respiratory atelectasis. Historically, clinical teams managed this pain with high-dose systemic opioids and intravenous patient-controlled analgesia pumps. However, systemic opioids frequently induce troubling adverse effects, including postoperative nausea, vomiting, dizziness, and prolonged sedation. In addition, respiratory depression poses a persistent risk in pediatric surgical units. Therefore, pediatric anesthesiologists actively pursue targeted regional anesthesia techniques. Regional fascial plane blocks effectively interrupt nociceptive input at the donor site while reducing reliance on systemic opioids.

Anatomy and Serratus Anterior Plane Block Technique

The serratus anterior plane block delivers local anesthetic into the fascial planes surrounding the serratus anterior muscle along the midaxillary line. Clinicians typically deposit local anesthetic either superficial or deep to the muscle at the fifth rib level. Anatomically, this plane contains the lateral cutaneous branches of the intercostal nerves derived from thoracic levels T2 through T9. Consequently, fluid spread within this space provides broad hemithoracic analgesia across the anterolateral chest wall.

Furthermore, real-time ultrasound guidance ensures exceptional anatomical accuracy and clinical safety. Practitioners directly visualize needle advancement, muscular fasciae, rib contours, and the underlying parietal pleura throughout injection. Therefore, anesthesiologists reliably avoid deep structures and prevent accidental pleural puncture. In contrast to central neuraxial techniques, this peripheral block avoids sympathetic blockade and hemodynamic instability. Moreover, the block produces dense somatic sensory blockade precisely over the donor cartilage incision site. Because the procedural technique is relatively simple and superficial, anesthesiologists can perform it quickly following endotracheal intubation. Thus, this interfascial approach represents a practical addition to modern pediatric anesthesia practice.

Analgesic Efficacy and Pain Score Trajectories

The systematic review and meta-analysis synthesized data from five randomized controlled trials involving 179 pediatric patients undergoing auricular reconstruction. Notably, the pooled outcomes demonstrated consistent early analgesia across all evaluated time points. Static rest pain scores reached a modest peak at twelve hours postoperatively, showing a pooled mean score of 3.28 on numeric rating scales. Subsequently, rest pain resolved steadily, falling to a low pooled mean score of 1.15 by forty-eight hours.

Similarly, dynamic cough pain peaked at twelve hours with a pooled mean of 4.35 before declining significantly over the following thirty-six hours. Controlling cough pain is crucial because dynamic discomfort directly determines pulmonary clearance and deep breathing capability in pediatric patients. In addition, the analysis calculated a pooled mean analgesic duration of 11.65 hours, providing durable relief through the critical first night. Furthermore, only 18.37% of pediatric patients required supplemental rescue analgesia during their recovery. Consequently, these pooled findings demonstrate that the block provides dependable analgesia during the most painful phase of surgical recovery.

Opioid Sparing and Enhanced Recovery Outcomes

Beyond mitigating subjective pain ratings, the regional block produces tangible improvements in recovery milestones. According to the pooled meta-analytic findings, cumulative twenty-four-hour patient-controlled intravenous analgesia consumption averaged only 55.65 milliliters. This low consumption confirms that effective sensory blockade substantially curtails systemic opioid reliance. Because children experience adequate somatic relief, they trigger fewer demand doses on intravenous analgesia devices.

Furthermore, reduced opioid exposure facilitates prompt postoperative emergence and rapid functional recovery. The pooled mean time to tracheal extubation was 14.31 minutes, demonstrating smooth emergence from general anesthesia. Moreover, pediatric patients achieved independent or assisted physical ambulation at a pooled mean of 18.68 hours following surgery. Early mobilization represents a cornerstone of modern enhanced recovery protocols. Specifically, early ambulation stimulates gastrointestinal motility, maintains muscular tone, and promotes patient well-being. When children mobilize without sharp donor-site pain, their hospital recovery proceeds smoothly. Therefore, incorporating regional chest wall blockade accelerates patient discharge readiness and improves surgical quality metrics.

Safety Profile and Institutional Integration

Safety considerations remain essential when choosing regional anesthesia techniques for pediatric surgical patients. Fortunately, the meta-analysis demonstrated an exceptionally reassuring safety profile for this ultrasound-guided procedure. Across the included trials, investigators documented zero cases of local anesthetic toxicity, pneumothorax, or major hematomas. The superficial plane allows continuous sonographic visualization, which significantly reduces the likelihood of needle misplacement.

Additionally, the incidence of opioid-related adverse events remained low among patients receiving the regional block. Postoperative nausea and vomiting occurred in 14.97% of children, while dizziness occurred in 6.10% and pruritus in only 1.77%. These low complication rates compare favorably with historical pediatric surgical cohorts who received systemic opioids alone. Furthermore, the block causes neither motor weakness in the extremities nor urinary retention. Consequently, clinicians can integrate this regional technique into standard multimodal regimens alongside acetaminophen and nonsteroidal anti-inflammatory agents. Preemptive block administration blunts intraoperative nociceptive signaling, stabilizes surgical hemodynamics, and supports gentle postoperative emergence. Ultimately, standardizing this block elevates quality of care in pediatric reconstructive centers.

Frequently Asked Questions

How does the serratus anterior plane block compare to local wound infiltration?

The serratus anterior plane block provides significantly broader and longer-lasting analgesia than local wound infiltration. By depositing local anesthetic within the fascial plane, this block reliably interrupts multiple lateral cutaneous branches of intercostal nerves. Consequently, pediatric patients achieve lower pain scores during rest and coughing, demand fewer supplemental opioids, and ambulate earlier than children who receive local wound infiltration alone.

What is the typical duration of analgesia provided by this block?

A single ultrasound-guided injection provides an average analgesic duration of 11.65 hours in pediatric patients. The block delivers peak relief during the initial twelve postoperative hours, covering the most painful postoperative phase. Although the local anesthetic effect gradually diminishes after twenty-four hours, scheduled multimodal non-opioid medications can easily maintain adequate patient comfort as donor-site surgical pain naturally subsides.

Does this regional block compromise pediatric respiratory mechanics or ventilation?

No, the serratus anterior plane block does not impair chest wall mechanics or compromise spontaneous ventilation. Because the injection targets sensory nerve branches rather than motor nerves, it spares the diaphragm and intercostal musculature. Furthermore, by relieving sharp donor-site pain, the block prevents voluntary chest wall splinting, preserves functional vital capacity, and reduces the risk of postoperative pulmonary atelectasis.

Disclaimer: This content is for informational and educational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Refer to the latest local and national guidelines for clinical practice.

References

1. Kodalak EA et al. Ultrasound-Guided Serratus Anterior Plane Block in Pediatric Microtia Reconstruction: A Systematic Review and Single-Arm Meta-Analysis. J Craniofac Surg. 2026 Sep 24. doi: 10.1097/SCS.0000000000013453. PMID: 42779548.
2. Chen CM, Xiang GH, Yan FX, et al. Ultrasound-guided Bilateral Serratus Anterior Plane Block for Postoperative Analgesia in Ear Reconstruction after Costal Cartilage Harvest: A Randomized Controlled Trial. Aesthetic Plast Surg. 2022;46(4):1753-1760.
3. Yang D, Wang Y, et al. Efficacy and safety of ultrasound-guided bilateral superficial serratus anterior plane block for postoperative analgesia in pediatric ear reconstruction with costal cartilage harvest: a randomized controlled trial. J Anesth. 2025;39(4):512-520.