hydrochloride in saline on blood loss following tangen- tial excision of burn wounds. Plast Reconstr Surg 1983; 72: 830–6. 4 Wang C, Martyn JA. Burn injury alters beta-adrenergic receptor and second messenger function in rat ventric- ular muscle. Crit Care Med 1996; 24: 118–24. Non-pharmacological relief of acute pain following total abdominal hys- terectomy To the Editor: Transcutaneous electrical nerve stimulation (TENS) has been used effectively to reduce postoperative pain. 1,2 Unfortunately, TENS is seldom available to the anes- thesiologist in the operation theatre. We undertook a study to observe the efficacy of peripheral nerve stimu- lator (PNS) induced electrical stimulation in compari- son to TENS as a mode of postoperative pain relief in patients undergoing elective total abdominal hysterec- tomy for the first 24 hr after surgery since both devices can deliver a similar configuration of current intensity and frequency. 3,4 Forty-five ASA I and II patients (mean age 50.6 ± 5.03 yr, mean weight 50.21 ± 6.39 kg) were selected for this study. The patients were randomly divided into three groups of 15 patients each. Group I received Sham TENS (with reversed electrodes), Group II received conventional TENS (frequency 100 Hz, intensity 40–60 mA) and Group III received electrical stimulation by PNS (frequency 100 Hz, intensity 10–20 mA) for pain relief. Each period of monophasic rectangular pulsed electrical stimulation 3,4 lasted for 20 min. This was administered on arrival in the recovery room and then eight and 16 hr later in the ward. Twenty minutes of TENS stimulation administered every eight hours has been reported earlier for relief of postoperative upper abdominal pain. 1 All patients received a uniform premedication, general anesthetic technique and postoperative care. Before applying the dressing, para-incision electrodes were applied to deliv- er electrical stimulation. Pain relief was graded as good = no pain, satisfac- tory = bearable pain not requiring rescue analgesia, unsatisfactory = unbearable pain requiring rescue anal- gesia (tramadol 2 mg·kg –1 ). It was observed that 66.66% and 73.33% patients of Groups II and III respectively had good postoperative analgesia during the study period (Table). On the contrary, 86.66% of the patients in the Sham TENS group had unsatisfac- tory pain relief. The mean doses of tramadol per kilo- gram body weight in the first 24 hr was 1.193 mg·kg –1 and 0.828 mg·kg –1 in Groups II and III respectively, compared to 3.680 mg·kg –1 in Group I patients. This difference between Groups II and III, compared to Group I was statistically significant (unpaired t test, P < 0.05). 73.33% and 80% of patients in Groups II and III respectively expressed their willingness to opt for a similar technique for postoperative pain relief in the future. We conclude that electrostimulation delivered with a PNS can provide good pain relief in the post- operative period in patients undergoing open abdom- inal hysterectomy. Pain relief was comparable to conventional TENS. Manpreet Singh MBBS Rashid M. Khan MD S. Bano MD Wasimul Huda MBBS Seema Hakim MD Namita Grover MBBS Aligarh, India References 1 VanderArk GD, McGrath KA. Transcutaneous electri- cal stimulation in treatment of postoperative pain. Am J Surg 1975; 130: 338–40. 2 Bayindir O, Paker T, Akpinar B, Erenturk S, Askin D, Aytac A. Use of transcutaneous electrical nerve stimula- tion in the control of postoperative chest pain after cardiac surgery. J Cardiothorac Vasc Anesth 1991; 5: 589–91. 530 CANADIAN JOURNAL OF ANESTHESIA TABLE Duration of satisfactory analgesia (hr) Time (hr) 0–6 6–12 12–18 18–24 No. of Pts % No. of Pts % No. of Pts % No. of Pts % Group I (n = 15 0 0.00 0 0 0 0 0 0 (Sham) Group II (n =15) 2 13.33 1 6.66 2 13.33 10 66.66 (TENS) Group III (n = 15) 2 13.33 1 6.66 1 6.66 11 73.33 (PNS) No. = number; Pts = patients; TENS = trancutaneous electrical nerve stimulation; PNS = peripheral nerve stimulator.