An International Trial to Evaluate the Efficacy and Safety of SABER®-Bupivacaine for Postoperative Pain Control in Patients Undergoing Hysterectomy

Pain intensity (PI) on movement AUC over the period 1 to 72 hours post-surgery. Subjects assessed their pain intensity using an 11-point Pain Intensity Numeric Rating Scale (PI-NRS) with NRS scores ranging from 0 (no pain) to 10 (worst pain possible). The AUC is computed for each patient using the standard trapezoidal rule and normalised by dividing by the time interval over which it is computed. This normalisation converts the AUC to the natural pain scale (NRS 0-10) to allow for better translation of the clinical treatment effect magnitude.

Cumulative IV morphine-equivalent dose of opioid rescue medication

Opioid-related side effects were recorded 0-7 days after surgery. The Opioid-Related Symptom Distress Scale (OR-SDS) is a composite score computed from a questionnaire containing frequent opioid-related symptoms (Fatigue, Drowsiness, Inability to concentrate, Nausea, Dizziness, Constipation, Itching, Difficulty with urination, Confusion, Retching/vomiting). For each symptom, patients assigned integer scores to assess severity (none=0 to very severe=4), bothersomeness (none=0 to very much=5), and frequency (none=0 to almost constantly=4); patients reported number of Retching/vomiting episodes (none=0, 1-2 episodes=1, 3-4 episodes=2, 5-6 episodes=3, >6 episodes=4).

On each day (Day 0-7), the score for each symptom was the mean of the three component scores, and the OR-SDS score was the overall mean of the 10 symptom scores, (values from 0 to 4; larger outcomes are worse). The mean of the daily OR-SDS score from Day 0 to 7 gave the overall OR-SDS Score.