To the investigators' knowledge, no study has looked at differences in postoperative pain when comparing maintenance of anesthesia with isoflurane, desflurane, sevoflurane, and propofol in laparoscopic cholecystectomy. The investigators' hypothesis is that total intravenous anesthesia with propofol will lead to less postoperative pain in the first 24 hours after laparoscopic cholecystectomy when compared to maintenance of anesthesia with isoflurane, desflurane or sevoflurane.