title: Ultrasound-guided transversus abdominis plane (TAP) block for laparoscopic gastric-bypass surgery: a prospective randomized controlled double-blinded trial.
abstract: BACKGROUND
  Despite the laparoscopic approach, patients can suffer moderate to severe pain following bariatric surgery. This randomized controlled double-blinded trial investigated the analgesic efficacy of ultrasound-guided transversus abdominis plane (TAP) blocks for laparoscopic gastric-bypass surgery.
  
  
  METHODS
  Seventy patients undergoing laparoscopic gastric-bypass surgery were randomized to receive either bilateral ultrasound-guided subcostal TAP block injections after induction of general anesthesia or none. All patients received trocar insertion site local anesthetic infiltration and systemic analgesia. The primary outcome was cumulative opioid consumption (IV morphine equivalent) during the first 24 h postoperatively. Interval opioid consumption, pain severity scores, rates of nausea or vomiting, and rates of pruritus were measured during phase I recovery, and at 24 and 48 h postoperatively.
  
  
  RESULTS
  There was no difference in cumulative opioid consumption during the first 24 h postoperatively between the TAP (32.2 mg [95% CI, 27.6-36.7]) and control (35.6 mg [95% CI, 28.6-42.5]; P = 0.41) groups. Postoperative opioid consumptions during phase I recovery and the 24-48-h interval were similar between groups, as were pain scores at rest and with movement during all measured intervals. The rates of nausea or vomiting and pruritus were equivalent.
  
  
  CONCLUSIONS
  Bilateral TAP blocks do not provide additional analgesic benefit when added to trocar insertion site local anesthetic infiltration and systemic analgesia for laparoscopic gastric-bypass surgery.
authors.affiliation: Department of Anesthesia and Pain Management, Toronto Western Hospital, University of Toronto, 399 Bathurst Street, Toronto, ON M5T 2S8, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: Albrecht
authors.forename: Kyle R
authors.initials: KR
authors.lastname: Kirkham
authors.forename: Ryan V W
authors.initials: RV
authors.lastname: Endersby
authors.forename: Vincent W S
authors.initials: VW
authors.lastname: Chan
authors.forename: Timothy
authors.initials: T
authors.lastname: Jackson
authors.forename: Allan
authors.initials: A
authors.lastname: Okrainec
authors.forename: Todd
authors.initials: T
authors.lastname: Penner
authors.forename: Rongyu
authors.initials: R
authors.lastname: Jin
authors.forename: Richard
authors.initials: R
authors.lastname: Brull
mesh_terms: D000009:Abdominal Muscles / Q000294:innervation; D000293:Adolescent; D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid; D000768:Anesthesia, General / Q000379:methods*; D002170:Canada / Q000453:epidemiology; D004311:Double-Blind Method; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods; D009767:Obesity, Morbid / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control; D017060:Patient Satisfaction; D020250:Postoperative Nausea and Vomiting; D011446:Prospective Studies; D011537:Pruritus; D013997:Time Factors; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D000701:Analgesics, Opioid