Intracavitary anaesthesia for medical thoracoscopy procedural pain: the CAMP randomised trial

Background: Medical thoracoscopy (MT) under conscious sedation can be a painful procedure. A pilot study reported reduction in procedural pain with lidocaine application via chest tube before procedure. This study aimed at assessing the extent of effect of intrapleural lidocaine on pain during MT in a double-blind randomised trial. Results: Thirty patients (mean age 483 years) were recruited, 14 randomised to the lidocaine group and 16 to the saline group. In four patients (two from each group), chest tube insertion prior to MT failed, and they were excluded from the final analysis. The mean (SD) visual analogue scale (VAS) pain score during procedure was 49 +/- 33.2 for the lidocaine group and 57.4 +/- 27.6 for the control group (mean difference - 8.4 points, p = 0.49). The VAS pain score as assessed by operator was 45.6 +/- 19.8 for the lidocaine group and 46.6 +/- 29.8 for the control group (p = 0.97). There was no difference in the VAS pain score at 120 min post MT or in the doses of sedatives used during procedure between the study groups. Conclusion: ICA for MT does not seem to improve procedural pain as suggested by previous studies.