Local infiltration of lidocaine versus lidocaine iontophoresis in pain relief during radial artery cannulation for open heart surgery

Traditionally, pain has been thought to be an unfortunate but inevitable part ofdisease and its treatment. Pain associated with medical procedures was ignored because it wasthought to be unavoidable. The question of why physicians should treat pain is as important asthe knowledge of preventing it, since it is a right measure to take. This study was conducted to compare the effectiveness of lidocaine iontophoresiswith that of local infiltration of lidocaine for the prevention and reduction of pain during radialartery cannulation, in patients undergoing open heart surgery. The present study comprised 60 adult patients, 36 males and 24 females, aged from29 to 84 years with a median age of 63.8 (±10.35 SD) and 65.4 (10.48±SD) for groups 1 and 2,respectively. The patients underwent elective open-heart surgery in Nemazee Hospital affiliatedto Shiraz University of Medical Sciences. Prior to induction of general anesthesia, patients wererandomly allocated to one of two groups for analgesia prior to radial artery cannulation on analternate week basis. Group 1 (n=30) patients received one-week analgesia using lidocaine iontophoresis,and analgesia in Group 2 (n=30) was performed using lidocaine infiltration the followingweek. Both groups were similar in terms of gender distribution. The VAS scores in group 1 were significantly lower than group 2 with no significantdifference in the difficulty of cannulations between the two groups. There was no complaint ofpain from patients during iontophoresis, and no report of any significant side effects. Slight skinerythma was noted after removal of the iontophoretic anode patch in 4 patients, which lasted forabout 0.5-4 hours. This study has demonstrated that lidocaine iontophoresis is a useful, non-invasive,rapid, painless alternative to lidocaine infiltration for dermal analgesia for radial ar