ABSTRACT
AIMS: External electrical cardioversion (EC) usually requires brief general anaesthesia involving anaesthetists. The aim of this study was to evaluate the feasibility and safety of inducing anaesthesia for EC of atrial fibrillation (AF) exclusively by the cardiologic team with anaesthetists on-hand. METHODS AND RESULTS: A retrospective analysis of 624 elective EC, over a 6-year period, was made. No patients were excluded due to the severity of pathology or comorbidities. The protocol of the intravenous anaesthesia was 5 mg bolus of midazolam and subsequent increasing doses of propofol starting from 20 mg to achieve the desired sedation level. After delivering DC shock, a direct observation period followed in order to assess the post-sedation recovery and to detect the procedure-related complications. Electrical cardioversion was effective in 98.9% of the cases. General anaesthesia was effective in 100% of cases with a dosage of propofol, ranging between 20 mg to a maximum of 80 mg, after 5 mg of midazolam was administered. All patients generally showed a fast recovery waking up in a few minutes. The anaesthesiology team was never called for assistance. All the procedures were carried out by the cardiologic team as planned. No thrombo-embolic and allergic complications were observed. Arrhythmic complications were uncommon and essentially bradyarrhythmias. CONCLUSION: A general anaesthesia for outpatient EC of AF can be safely handled by a cardiologist having adequate experience with anaesthetical agents. Moreover, the association of midazolam and a very small dosage of propofol, given their synergic action, is effective and safe in inducing anaesthesia. Arrhythmic complications are rare and limited to bradyarrhythmias.
Subject(s)
Anesthesia, General/methods , Anesthesia, Intravenous/methods , Anesthetics, Intravenous/administration & dosage , Atrial Fibrillation/surgery , Electric Countershock , Midazolam/administration & dosage , Propofol/administration & dosage , Aged , Anesthetics, Intravenous/adverse effects , Bradycardia/etiology , Female , Humans , Male , Midazolam/adverse effects , Middle Aged , Propofol/adverse effects , Retrospective Studies , Treatment OutcomeABSTRACT
BACKGROUND: Outpatient electrical cardioversion (EC) of atrial fibrillation is currently the standard of care. Shock-related arrhythmias may be particularly deleterious in this setting. Preoperative identification of high-risk patients may be very useful. METHODS: A retrospective analysis was made of 543 consecutive elective EC procedures in 457 outpatients over an 8-year period in a university cardiological institute. The protocol included adequate anticoagulation, intravenous anesthesia, direct current shock, and a direct observation after a shock to detect procedure-related complications. No patients were excluded due to severity of pathology or comorbidities. Clinical characteristics, energy delivered, medications, arrhythmic phenomena, and predictors of success and complications were analyzed. RESULTS: Of 543 ECs performed, 88.2% restored sinus rhythm, which persisted at discharge in 83.2%. No anesthesia-related complications were detected. No thromboembolic complications were detected. Use of a biphasic cardioverter was the only predictor of success (P = 0.0001). The bradyarrhythmic complication rate was 1.5%. No ventricular arrhythmic events were detected. Atrial flutter was present in five of eight patients who developed complications versus 44 of 535 patients who had no complications (P < 0.0005), and prosthetic heart valves in four of eight complicated versus 40 of 535 uncomplicated cases (P = 0.0044). The combination of atrial flutter and prosthetic heart valve was found in four of eight complicated versus 11 of 535 uncomplicated cases (P < 0.0005). CONCLUSION: Shock-related arrhythmias are essentially bradyarrhythmias. Atrial flutter and previous cardiac surgery identify a subgroup of patients at high risk of postshock bradyarrhythmic complications.
