Intraperitoneal Aerosolized Delivery of a Local Anesthetic for Post Operative Pain Management. A Double Blind, Randomised Controlled Clinical Trial.

Clinical Protocol for the Prospective Double Blind Randomised Controlled Trial for the Use of Intraperitoneal Aerosolized Local Anesthetic

The purpose of this study is to determine the effectiveness of aerosolized pain medication (.5% bupivicaine) delivered into the peritoneal cavity after laparoscopic gastric bypass surgery. This double blind study will include 50 patients. 25 will receive the aerosolized pain medication and 25 will receive a placebo (normal saline). All 50 patients will receive routine/typical methods of post-operative pain management. Post operative pain scores of the patients will be examined to determine the effect of aerosolization.

Surgical Technique

1. 30 mls of 0.5% bupivacaine with epinephrine standard dose will be distributed into the trocar site wounds after desufflation of the peritoneal cavity.
2. All the patients will be under a consistent intra-abdominal pressure using CO2 and the laparoscopy will be carried out using the same, routine / typical surgical instruments.

A. Control Group (n=25): Aerosolized normal saline will be introduced at the end of the procedure, using a specially designed sterile catheter. The catheter will be inserted via trocar port under direct vision. The other end of the catheter will be connected to a 72" Edwards Lifesciences pressure tubing (Ref: 50P172), which will be connected to a B&D 20cc syringe filled with 15 ml of normal saline and inserted into a specially designed syringe pump and pressurizing system designed to aerosolize the specified agent. The total dose of patient delivered normal saline will be 10 ml, with 5 ml remaining contained and undelivered within the catheter and 72" pressure tubing. Routine/Typical methods of post-operative pain management will be employed.

B. Aerosolized anesthetic (n=25): at the end of the procedure, the aerosolized local anesthetic will be introduced using a specially designed sterile catheter. The catheter will be inserted via trocar port under direct vision. The other end of the catheter will be connected to a 72" Edwards Lifesciences pressure tubing (Ref: 50P172), which will be connected to a B&D 20cc syringe filled with 15 ml of anesthetic agent and inserted into a specially designed syringe pump and pressurizing system designed to aerosolize the specified agent. The total dose of patient delivered anesthetic will be 10 ml, with 5 ml remaining contained and undelivered within the catheter and 72" pressure tubing. Routine/Typical methods of post-operative pain management will be employed.

Inclusion Criteria:

1. Male or female patients between the ages of 18-65
2. Patients in general good health requiring elective surgery

Exclusion Criteria:

1. Female patients that are pregnant
2. Patients allergic to bupivicaine
3. Patients who have used narcotic drugs within 30 days of the surgical procedure.