Transversus Abdominis Plane Block in Children Undergoing Open Pyeloplasty Surgery

Transversus Abdominis Plane Block in Children Undergoing Open Pyeloplasty Surgery

The purpose of this study is to evaluate the effectiveness of transversus abdominis plane (TAP) block in reducing postoperative opioid requirements and pain after open pyeloplasty surgery in children.

Primary open pyeloplasty is a common elective surgical procedure at The Hospital for Sick Children. All children are given fentanyl plus local anesthetic wound infiltration for intraoperative analgesia. A retrospective audit demonstrated that 63% of children required additional opioid treatment in the early recovery period following surgery. Concern exists regarding potential side effects of opioids including nausea or vomiting, respiratory depression, pruritus, over-sedation and delayed transition to oral intake. More importantly, children may under-report their pain or pain may not be recognized by medical staff leading to inadequate provision of analgesia. This suggests that the use of a regional technique, such as a TAP block, may benefit children undergoing open pyeloplasty.

The ultrasound guided TAP block introduces a local anaesthetic to the transversus abdominis plane which is one of three muscle layers in the abdominal wall. This results in a block of the nerves leading to the abdominal wall thereby reducing pain sensations.

Inclusion Criteria:

• American Society of Anesthesiologists (ASA) classification score 1-3
• age 1 month to 6 years inclusive

Exclusion Criteria:

• children undergoing an additional surgical procedure at an anatomical location not covered by a unilateral TAP block during the same anesthetic
• children in whom a TAP block is contraindicated, i.e. surgical scar or distorted anatomy at the site of injection
• postoperative admission to the intensive care unit
• children with a known allergy to bupivacaine
• children with a history of chronic abdominal pain requiring opioid analgesics
• children with known renal insufficiency
• children with known impaired hepatic function
• children with known impaired cardiac function
• children known hypersensitivity to sodium metabisulfite