Ultrasound-guided lower forearm median nerve block in open surgery for trigger thumb in 1- to 3-year-old children: A randomized trial.

Background And Aim: Trigger thumb is a common hand disability in children and is primarily treated with open surgery. A conscious median nerve block can usually meet the requirements for trigger thumb-releasing surgery in adults; however, its effectiveness in children requires further clarification. The present study aims to demonstrate whether ultrasound-guided lower forearm median nerve blockade is a viable option for children undergoing open surgery for trigger thumb.

Methods: A prospective randomized study was designed to compare median nerve blocks guided by ultrasonography with those guided by anatomic landmarks. Following induction of general anesthesia, the children received a median nerve block performed either by ultrasound-guided block of the lower forearm (group U) or landmark-based blocking at the proximal wrist crease level (group T) with a 0.2% ropivacaine injection. The success rates were compared between groups as the primary endpoint; additional sufentanil and propofol administration, anesthesia recovery time, and other secondary endpoints were also compared.

Results: A total of 100 children (age 1-3 years) with ASA status I who were scheduled for open surgery for trigger thumb were included in this study (n = 50 per group). Thirty-seven children in group T and 50 children in group U underwent successful blocks. The rate of unsuccessful blockade was significantly lower in group U than group T (0% and 26%, respectively), and rate of additional sufentanil and propofol administration was also lower in group U than in group T.

Conclusion: Ultrasound-guided lower forearm median nerve block can provide more effective analgesia, a higher success rate, and lower general and local anesthetic dosages than the anatomic landmark-based blocking method in children undergoing open surgery for trigger thumb.