Impact of Acetazolamide in Reducing Referred Postoperative Pain

Impact of Acetazolamide in Reducing Referred Postoperative Pain After Robotic Assisted Laparoscopic Prostatectomy

Robotic assisted laparoscopic prostatectomy (RALP) is the standard treatment for prostate cancer, due to the benefits of decreased blood loss and length of stay.The procedure involves removing a man's prostate using a minimally invasive robotic approach under the guidance of a surgeon. In order to gain sufficient access, carbon dioxide (CO2) is used to fill the surgical space in a process termed insufflation. Carbon dioxide is a mainstay in laparoscopic procedures because it is cost-effective, noncombustible and readily excreted via the respiratory system in healthy patients. Insufflation with CO2, however, has been linked to post-operative referred pain secondary to peritoneal acidosis.This acidosis is suspected to be due to the formation of carbonic acid from the CO2 insufflation.Peritoneal acidosis, and its associated post-operative referred pain, may not be adequately treated with the current standard pain control regimen.

Group 1 (acetazolamide): Patients undergoing RALP with the peri-operative use of one-time 250 mg dose of acetazolamide

Group 2 (placebo): Patients undergoing RALP with the peri-operative use of 10 mL normal saline as placebo.

Being that adequate pain control is essential to recovery in the post-operative setting, efforts have been made to address this pain at its root. Prior studies have demonstrated that preoperative administration of acetazolamide decreased post-operative referred pain in the immediate post-surgical period.

Group 2 (placebo): Patients undergoing RALP with the peri-operative use of 10 mL normal saline as placebo.

Visual Analogue Scale (VAS) 10-cm lines anchored at the ends by words that define the bounds of various pain dimensions. The patient is asked to place a vertical mark on the scale to indicate the level of intensity of his pain.

The primary outcome to be assessed is the absolute change in VAS score both in general and at the shoulder tip. This will be measured as the difference between the VAS score obtained pre-operatively, when first responsive after surgery in the post anesthesia care unit (PACU), immediately prior to leaving PACU, and throughout the hospital stay per standard of care. Δ VAS = Postoperative VAS - Preoperative VAS VAS is a testing technique for measuring subjective or behavioral phenomena (as pain or dietary consumption) in which a subject selects from a gradient of alternatives (as from "no pain" to "worst imaginable pain" or from "every day" to "never") arranged in linear fashion -abbreviation VAS

Inclusion Criteria: • Male patients ≥18 years of age undergoing robotic-assisted prostatectomy Exclusion Criteria: Patients with renal insufficiency with serum creatinine >2.0 mg/dl Patients with renal transplant Patients with pre-existing metabolic acidosis Patients with chronic obstructive pulmonary disease Patients with hepatic disease Patients with central nervous system disorders Patients with hematological disease history Patients with pre-existing electrolyte abnormalities Patients with hypovolemia Patients with lithium or diuretic usage Patients with sulfonamides allergy Patients with American Society of Anesthesiologists physical status 4 or 5