Background: Posterior spinal fusion (PSF) for adolescent idiopathic scoliosis causes significant postoperative pain and high opioid requirements. Methadone, with dual μ- and κ-opioid agonism and NMDA antagonism, provides long-acting analgesia and may reduce perioperative opioid use. This study evaluated whether perioperative low-dose methadone (0.1 mg/kg) improves postoperative pain and opioid outcomes after pediatric PSF. Methods: In this single-center retrospective cohort study (January 2019–June 2023), pediatric patients <23 years old undergoing PSF were categorized by perioperative methadone exposure (intraoperative and/or postoperative) versus no methadone. The primary outcome was total postoperative opioid consumption (morphine milligram equivalents per kilogram, MME/kg) over postoperative days (POD) 0–3. Secondary outcomes were average daily pain scores and hospital length of stay (LOS). Inverse probability weighting (IPW) adjusted for age, sex, and protocol period. Results: A total of 339 patients (51% no methadone, 49% methadone; mean age 14.6 ± 2.5 years; 76% female) were analyzed. Methadone patients had longer anesthesia (392 vs. 372 min, p = 0.042) and surgery times (287 vs. 266 min, p = 0.01). IPW-adjusted associations show postoperative opioid use was significantly higher in the methadone group on POD 0 (median 2.5 vs. 2.1 MME/kg in no methadone group; p = 0.005). No significant differences were found in postoperative average pain scores (e.g., mean NRS: 2.3 vs. 2.5 on POD 0, p = 0.12) and LOS (3.3 vs. 3.1 days, p = 0.38) between methadone group and no methadone group. Discussion: Perioperative methadone provided similar analgesia for pain management and recovery without prolonging hospitalization, despite higher early opioid use on POD 0. Retrospective design limits causal inference, and residual confounding may persist despite propensity score-based adjustments. Further prospective trials are required to establish safety and dosing. Conclusions: In this retrospective cohort, perioperative low-dose methadone was associated with higher early postoperative opioid use but no significant differences in pain scores or length of stay compared with standard regimens. Methadone did not demonstrate an opioid-sparing effect in this real-world setting. Prospective studies are needed to better define its role and safety in pediatric posterior spinal fusion.

Background: Thoracic paravertebral catheters are increasingly used in neonates to avoid neuraxial techniques during thoracoscopic tracheoesophageal fistula (TEF) repair. Catheter fracture and retention are exceedingly rare in this population, and optimal management remains undefined. Learning Objectives: Recognize this complication risk in neonatal paravertebral placement; identify appropriate imaging when retention is suspected; discuss conservative and surgical approaches; and understand the importance of early transparent communication with caregivers. Case: A 2-day-old term neonate weighing 2.90 kg underwent thoracoscopic repair of type C tracheoesophageal fistula with intraoperative placement of an ultrasound-guided right paravertebral catheter for continuous analgesia. The catheter was placed at the T5 vertebral level using a 20 G, 2-inch Tuohy needle with an in-plane lateral-to-medial approach. Saline hydrodissection was used to confirm entry into the paravertebral space. A 24 G radiopaque Perifix One catheter was initially inserted but proved difficult to advance. During attempted removal, some resistance was encountered, and both the needle and catheter were withdrawn together. Subsequent inspection suggested possible catheter shortening, raising concern for a retained fragment. A second catheter of size 20 G advanced via an 18 G needle was then successfully placed at the same level and was removed without complications on postoperative day 3. Comparison with an intact reference catheter revealed that the first-placed 24 G catheter was approximately 1.5 cm shorter, although the tip appeared intact. The pain physician promptly notified both the clinical teams and the family. One month later, during routine imaging for respiratory distress, a curvilinear opacity was noted at the T9 vertebral level. Dedicated thoracic spine films confirmed a 7 mm retained paravertebral catheter fragment. Multidisciplinary consensus (pain team, anesthesia, NICU, and surgery) determined that the fragment was small, non-metallic, and remote from critical structures. Conservative management with long-term follow-up was chosen. The family was informed early during initial suspicion and again upon confirmation. At 17-month follow-up, the child remained asymptomatic. Discussion: Retained catheter fragments are rare in pediatric regional anesthesia and may be radiographically occult early. In neonates, re-operation for a tiny, inert foreign body may cause more morbidity than observation. Prevention depends on appropriate equipment selection, catheter integrity checks pre- and post-placement, careful technique, and attention to resistance or difficulty during advancement or removal. Clear and timely communication with caregivers preserves trust when complications or iatrogenic uncertainty arise. Conclusions: In this neonate, a small retained paravertebral catheter fragment was identified incidentally and was safely managed with conservative observation. When such fragments are non-metallic, stable, and located away from critical structures, non-operative management with close follow-up may be an appropriate and safe approach.