METHODS	Eighty ASA ( American Society of Anesthesiologists ) 1 and 2 patients were randomly assigned to receive either 20 ml of 0.5 per cent bupivacaine ( n = 39 ) or the same volume of saline ( n = 41 ) instilled under direct vision into the hepatodiaphragmatic space , near and above the hepatoduodenal ligament and above the gall bladder bed at the end of surgery .\