Randomized Trial of Wound Infiltration With Extended-release Bupivacaine Before Laparoscopic or Robotic Hysterectomy

Lidocaine and bupivacaine hydrochloride (HCl) are the most commonly used drugs for wound infiltration during laparoscopic surgery for post-operative pain control. There is some evidence that wound infiltration decreases immediate post-operative pain. While bupivacaine has a slightly slower onset of action (5-10 minutes), it has become the preferred injectable anesthetic for surgical use because of its longer duration of effect (4-8 hours versus 1-2 hours for lidocaine).

DepoFoam bupivacaine (EXPAREL, Pacira Pharmaceuticals, Inc., Parsippany, NJ, USA) is a newer extended-release formulation of bupivacaine HCl approved by the U.S. Federal Drug Administration in October 2011. In this suspension, bupivacaine is encapsulated in microscopic spherical lipid-based particles of varying size to allow dispersion of the drug over an extended period of time. Analgesia is prolonged up to 96 hours. Given the extended duration of action, this liposomal bupivacaine may be better at providing post-operative pain relief in laparoscopic surgery.

Phase three trials have shown better pain control in the first 24 hours and less opioid use overall in bunionectomies, hemorrhoidectomies, and total knee replacement surgery when compared to placebo. No studies, however, have been published evaluating extended-release liposomal bupivacaine for laparoscopic surgery, or gynecologic surgery in general. Currently, we are using liposomal bupivacaine for pain relief after laparoscopic hysterectomies, but as stated, it has never been formally evaluated.

We hypothesize that liposomal bupivacaine ("extended-release") provides extended pain relief and decreases the need for supplemental opioid use after major laparoscopic surgery. We will be evaluating whether pre-incision infiltration of extended-release bupivacaine decreases post-operative pain from laparoscopic and robotic-assisted hysterectomy compared to bupivacaine HCl ("short-acting"). To achieve this evaluation we designed a double-blinded randomized controlled trial.

Patients who are scheduled to undergo a laparoscopic or robotic-assisted hysterectomy will be invited to participate. Group A will receive pre-incision infiltration of each trocar site with 4 ml of 0.25% Bupivacaine HCl. Group B will receive pre-incision infiltration of each trocar site with 4 ml of extended-release bupivacaine (EXPAREL) (13.3mg/ml). Subjects and outcome assessors will be blinded to group allocation.

Data will be collected while patients are in the hospital on pain levels and consumption of opioid pain medications. Upon discharge, pain levels, functioning, and quantity of opioid and non-steroidal anti-inflammatory (NSAID) pain medications will be collected through online questionnaires. Subjects will be followed until their 2-3 weeks post-operative visit.

Inclusion criteria

• Benign indication for surgery
• Planned multiport laparoscopic or robotic assisted hysterectomy
• Non-pregnant
• Able to provide informed consent
• Owns smartphone or computer with internet access
• Willing to provide contact phone number and accept SMS text messages
• Ability to speak and read English (because texts and online surveys will be in English only)

Exclusion criteria

• Planned additional procedures (e.g. incontinence surgery, prolapse repair or bowel surgery)
• Contraindication to study drug

• Severe Hepatic disease
• Severe Kidney disease
• Current use of monoamine oxidase inhibitors
• Current use of tricyclic antidepressants
• History of substance or alcohol abuse within the past 2 years