RT Journal Article SR Electronic T1 #36466 Safety and analgesic efficacy of ultrasound guided costo-transverse block in children undergoing open pyeloplasty: a case series JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP A332 OP A332 DO 10.1136/rapm-2023-ESRA.631 VO 48 IS Suppl 1 A1 Bhoi, Debesh A1 Sundharesan A, Meenakshi YR 2023 UL http://rapm.bmj.com/content/48/Suppl_1/A332.abstract AB Please confirm that an ethics committee approval has been applied for or granted: Not relevant (see information at the bottom of this page) Application for ESRA Abstract Prizes: I don’t wish to apply for the ESRA PrizesBackground and Aims Safe & effective perioperative analgesia is required for early recovery after open pyeloplasty surgeries. A single-shot caudal block is a widely accepted choice, however, it does not provide prolonged analgesia, and the addition of an adjuvant come with its inherent adverse effects. US- guided costo transverse block (CTB) has recently been introduced with cadaveric studies and clinical case reports, showing promising perioperative analgesia.Methods After parental written informed consent, US-guided costo transverse block (CTB) was performed after general anesthesia (prone position) in 10 ASA I patients (mean age 3.95 yrs, weight 14.4 kg), scheduled for pyeloplasty surgery and 2mg/kg of 0.2% ropivacaine was deposited at three levels (thoracic T9-10,10,11,& 11,12). (figure1) Intraoperatively all patients received IV paracetamol and continued 6th hourly. Any pain response was not relieved by consolation and IV paracetamol was managed with fentanyl rescue(0.5mcg/kg)Results The mean duration of surgery was 137 minutes. Intraoperatively 4 patients required fentanyl rescue. The mean time to rescue analgesic(fentanyl) not controlled by consolation and IV Paracetamol was 3 hrs, however, it was observed only in two patients. (table 1) None of the patients had any incision response. All the patients recovered well with a median FLACC on awakening 1/10 (0-2). All the patients had a good sleep with a median FLACC at 24 hours of 0/10( 0-1) and a maximum FLACC score of 4 in only one patient. (figure 2) We did not observe any procedure or local anesthetic- related complicationsAbstract #36466 Figure 1 Costo-transverse block needlingView this table:Abstract #36466 Table 1 Patients demography & Perioperative analgesiaAbstract #36466 Figure 2 FLACC scaleConclusions US-guided CTB with multimodal analgesic provides safe and effective perioperative analgesia in pediatric open pyeloplasty surgeries.