We studied 20 day case gynaecological laparoscopy patients, who had an erect chest X ray taken before discharge. Patients were telephoned the next day for a semi-structured interview. Particular note was made of shoulder tip pain and pain relieved by changing posture. The X ray was analysed for measurements of the length of arc and height of the gas bubble under each hemi-diaphragm, from which an estimation of bubble volume was also made. We found statistically significant correlations between both the length of arc (p = 0.005) and volume of gas bubble (p = 0.008) on the right side, with the pain score. Residual gas can be a prominent cause of post-laparoscopy pain.
