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Sir,—In a recent issue, Lipscomb and colleagues1 reported on the implantation of cardioverter defibrillators (ICD) under sedation and local anaesthesia. In July 1997 we also began implantation of ICD devices under local anaesthesia, in conjunction with intravenous sedation using non-anaesthetic agents, in response to logistical problems in obtaining general anaesthetics coupled with the development of smaller devices. We have prospectively collected data on 34 consecutive implantations—28 men and six women (mean age 61, range 30–76) with mean left ventricular ejection fraction of 32% (range 15–70) of whom 29 had ischaemic heart disease. The presenting arrhythmia was ventricular fibrillation (VF) in seven, sustained ventricular tachycardia (VT) in 26, and non-sustained VT in one patient.
Like those of Lipscomb et al all procedures were performed in the catheter laboratory. Oxygen via nasal prongs was given routinely and monitored by pulse oximetry; two patients with poor left ventricular function were additionally monitored with arterial lines. Subcutaneous 1% lignocaine was administered in the usual fashion. However, our technique differs from that of Lipscomb et alin terms of the analgesia and sedation, lead insertion, and device testing, seemingly without detriment to the safety and acceptability of the procedure. Diazepam 5–15 mg (mean 9.2) was given at the start of the procedure with additional aliquots during subpectoral pouch formation and defibrillation threshold testing as required (mean 3.8 mg). Before fashioning the subpectoral pouch, intravenous pethidine 25 mg was given in all but one case, and an additional 25 mg was required in seven cases. Lipscomb et al comment on the importance of performing a subclavian puncture in the subpectoral tissue plane to avoid mechanical lead fracture; we have performed lead insertion in the more conventional fashion with elective cephalic vein cannulation if possible (23 patients) as with all of our previous implantations under general anaesthesia. Finally, to minimise discomfort to the patient we have avoided the use of low energy shocks to determine high voltage lead impedance before defibrillator threshold testing with no adverse consequences (mean impedance 57 ohms (range 43–72)), and for the same reasons we have aimed to induce VF with high frequency stimulation (31 cases) rather than T wave shocks (three cases).
Not withstanding these differences in technique, our experience confirms the previous findings of excellent safety and tolerability. No significant complications occurred periprocedurally or at follow up. Patients tolerated the procedures well and 18 were discharged home the following day (mean hospital stay 2.2 days, range 1–10). We believe that by implanting the defibrillators under local anaesthesia and intravenous sedation we have considerably improved efficiency of implantation and reduced hospital stay; patients no longer need to wait for general anaesthesia availability but can be scheduled during a routine cardiac laboratory list. We whole heartedly endorse the conclusions of Lipscomb et al that subpectoral ICD placement may be performed safely and tolerably under local anaesthesia and sedation in the cardiac catheter laboratory.