Figure 2: Duration of analgesia in the 2 patient groups. Minimum duration of analgesia for bupivacaine is 5.92 hours, maximum duration is 11 hours, the IQR is 6.31-10.46 hours, and the median is 8.4 hours. For ropivacaine, minimum duration of anesthesia is 5.75 hours, maximum duration is 13 hours, the IQR is 6.75-10.25 hours, and the median is 8 hours.