Study ObjectiveTo evaluate the effects of peritoneal cold nebulization of ropivacaine on pain control after gynecologic laparoscopy. DesignEvidence obtained from a properly designed, randomized, double-blind, placebo-controlled trial (Canadian Task Force classification I). SettingTertiary care center. PatientsOne hundred thirty-five women with American Society of Anesthesiologists disease classified as ASA I-III who were scheduled to undergo operative laparoscopy. InterventionPatients were randomized to receive either nebulization of 30 mg ropivacaine before surgery (preoperative group), nebulization of 30 mg ropivacaine after surgery (postoperative group), instillation of 100 mg ropivacaine before surgery (instillation group), or instillation of saline solution (control group). Nebulization was performed using the Aeroneb Pro device. Measurement and Main ResultsPain scores, morphine consumption, and ambulation time were collected in the post-anesthesia care unit and at 4, 6, and 24 hours postoperatively. One hundred eighteen patients completed the study. Patients in the preoperative group reported lower pain Numeric Ranking Scale values compared with those in the control group (net difference 2 points; 95% confidence interval [CI], 0.3–3.1 at 4 hours, 1–3 at 6 hours, and 0.7–3 at 24 hours; p = .01) Patients in the preoperative group consumed significantly less morphine than did those in the control group (net difference 7 mg; 95% CI, 0.7–13; p = .02). More patients who received nebulization walked without assistance within 12 hours after awakening than did those in the instillation and control groups (net difference 15%; 95% CI, 6%–24%; p = .001). ConclusionsCold nebulization of ropivacaine before surgery reduced postoperative pain and morphine consumption and was associated with earlier walking without assistance.