| Abstract: | This paper describes a randomised controlled trial to evaluate the effectiveness of TENS in controlling pain following coronary artery bypass grafting (CABG). A total of 59 men undergoing CABG with internal mammary artery (IMA) at Bristol Royal Infirmary were randomly allocated to receive TENS or placebo in conjunction with patient-controlled analgesia (PCA) for one hour on their first postoperative day. A visual analogue pain score and the hourly usage of the PCA were recorded before, during and after the application of TENS or placebo. The results show that although pain scores were significantly reduced in the hour in which TENS was applied, there was no significant difference in this reduction between the TENS and placebo groups. PCA use by patients during the study period was limited, with the majority making none or one successful request per hour. The results imply that the observed reductions in pain were due to a placebo effect and that the use of TENS in conjunction with PCA following CABG with IMA is unlikely to confer a clinically important reduction in post-operative pain. |
