Novel Technique of Analgesia Following Open Liver Resection

Multicentre Evaluation of a Novel Technique of Analgesia Following Open Liver Resection: Medial Open Transversus Abdominis Plane (MOTAP) Catheters

Abdominal wall incisions used for liver surgeries are associated with significant postoperative pain and disability. Epidural analgesia is often contraindicated in these patients due to common bleeding problems. Furthermore, drugs such as acetaminophen and opioids are often inadequate and can lead to detrimental side-effects. Abdominal wall (AW) catheters can be placed during surgical closure along the incision line and can be used to administer local anesthetics for postoperative pain. The study is a multi-centre, double-blind, randomized controlled trial involving 120 patients undergoing elective liver surgery. Patients will be randomly assigned to AW catheter group treated with drug or control treated with saline. Treatment group will receive AW catheters with ropivacaine plus standard patient controlled analgesia (PCA). Control group will obtain AW with normal saline and no local anesthetics and PCA. Patients are followed for 6 months post-operatively for pain scores, side-effects, chronic pain and complications.

Control group will have saline 20cc of 0.9% normal saline injected into the catheters and then run at 5ml/hr for 72 hours

20cc of 0.2% ropivacaine will be injected in two equal divided doses through the two catheters then run at 5ml/hr for 72 hours

The primary endpoint is mean cumulative postoperative opioid consumption over the first two postoperative days (48 hours). Both intravenous PCA opioids and oral opioids will be recorded from the patient's medical records daily, converted to morphine equivalents, and compared between the two groups. The following information will be collected at regular intervals as a measure of the primary endpoints: Cumulative i.v. PCA opioid consumption every 12 hours for 72 hours as well as total opioid consumption for the entire hospital stay.

PCA opioid consumption every 12 hours for 72 hours as well as total opioid consumption for the entire hospital stay.

Inclusion Criteria: >18 years age Undergoing liver resection using a subcostal incision Exclusion Criteria: Patients unable to comprehend instructions, consent, or co-operate with pain assessment (including psychiatric disorders, pre-operative sedation, coma) Allergy to any study medications Patient not able to be extubated postoperatively for any clinical reason Laparoscopic surgery Co-existing epidural or intrathecal analgesia Chronic pain disorders or on long-term opioid use History of substance or alcohol abuse Transplant donor liver resections Patients with liver cirrhosis

Page MG, Karanicolas PJ, Cleary S, Wei AC, McHardy P, Ladak SSJ, Ayach N, Sawyer J, McCluskey SA, Srinivas C, Katz J, Coburn N, Hallet J, Law C, Greig P, Clarke H. In-hospital opioid consumption, but not pain intensity scores, predicts 6-month levels of pain catastrophizing following hepatic resection: A trajectory analysis. Eur J Pain. 2019 Mar;23(3):503-514. doi: 10.1002/ejp.1324. Epub 2018 Nov 8.

Karanicolas PJ, Cleary S, McHardy P, Kiss A, Sawyer J, Behman R, Ladak S, McCluskey SA, Srinivas C, Katz J, Coburn N, Law C, Wei AC, Greig P, Hallet J, Clarke H. Medial Open Transversus Abdominis Plane (MOTAP) Catheters Reduce Opioid Requirements and Improve Pain Control Following Open Liver Resection: A Multicenter, Blinded, Randomized Controlled Trial. Ann Surg. 2018 Aug;268(2):233-240. doi: 10.1097/SLA.0000000000002657.

Karanicolas P, Cleary S, McHardy P, McCluskey S, Sawyer J, Ladak S, Law C, Wei A, Coburn N, Ko R, Katz J, Kiss A, Khan J, Coimbatore S, Lam-McCulloch J, Clarke H. Medial open transversus abdominis plane (MOTAP) catheters for analgesia following open liver resection: study protocol for a randomized controlled trial. Trials. 2014 Jun 21;15:241. doi: 10.1186/1745-6215-15-241.