Setting The study setting was hospital. The economic analysis appears to have been carried out in the USA.

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1 Electrical cardioversion of atrial fibrillation or flutter with conscious sedation in the age of cost containment Goldner B G, Baker J, Accordino A, Sabatino L, DiGiulio M, Kalenderian D, Lin D, Zambrotta V, Stechel J, Maccaro P, Jadonath R Record Status This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn. Health technology The intervention health technology was conscious sedation (benzodiazepine-opioid) administered by certified electrophysiologists during elective cardioversion of atrial fibrillation/atrial flutter to sinus rhythm. The protocol used for the cardioversion involved the attachment of the patient to a monitor, blood pressure cuff, and defibrillator by external pads; with a nurse certified in the administration of conscious sedation infusing 1 mg of midazolam intravenously after obtaining baseline vital signs with the presence of the attending physician; then observing the patient over the next 3 to 5 minutes for level of consciousness, assessed by response to mild tactile and verbal stimulation. If the patient required more sedation, 1 to 2 mg of morphine sulfate and midazolam were administered every 3 to 5 minutes to achieve adequate sedation. The patient was deemed adequately sedated when there was no response to soft verbal and mild tactile stimuli yet respiratory drive was still intact. In this state, the patients were able to be aroused by vigorous stimuli but quickly fell back to sleep without recollection of the stimuli. An anaesthetist was always available for emergencies and known to be less than 5 minutes from where the cardioversion took place. The electrophysiologist and nurse were both certified in advanced cardiac life support, such that they could provide ventilatory support with a bag-mask valve while waiting for sedatives to clear, an anaesthetist to arrive, or for flumazenil or naloxone to take effect. When adequate sedation was achieved, cardioversion was performed with 50 to 360 J of synchronised energy. Once the cardioversion procedure was completed, the patient recovered for 3 hours, with vital signs assessed every 10 to 15 minutes for the first hour and every 30 minutes for the second and third hours. Outpatients were then asked to ambulate for 1 hour before discharge. Inpatients were returned to a monitored unit after the first hour of recovery and were permitted to ambulate after the third hour. Type of intervention Secondary prevention. Economic study type Cost-effectiveness analysis. Study population The study population consisted of patients with haemodynamically stable persistent atrial fibrillation and flutter. Patients who were haemodynamically unstable were excluded from the study. Setting The study setting was hospital. The economic analysis appears to have been carried out in the USA. Dates to which data relate No dates were given for the effectiveness and resource use data collection. The price year was Source of effectiveness data Page: 1 / 5

2 The evidence for the final outcomes was based on a single study. Link between effectiveness and cost data Costing was conducted on the same patient sample as that used in the effectiveness analysis. It is not entirely clear whether the costing was performed prospectively or retrospectively. Study sample Power calculations were not used to determine the sample size. Group 1 (patients who were scheduled to be electively cardioverted from atrial fibrillation or flutter to sinus rhythm with the help of an anaesthesiologist using propofol) consisted of 33 patients, mean age 69 years (SD: 14) and 70% male. Group 2 (patients who were scheduled to be cardioverted by an electrophysiologist certified in the administration of conscious sedation (benzodiazepine-opioid)) consisted of 26 patients, mean age 63 years (SD: 12) and 65% male. Study design The study appears to have been a prospective cohort study carried out in a single centre. The duration of follow-up was until discharge. The study had no loss to follow-up. The selection of patients into the study groups depended on scheduling constraints. Analysis of effectiveness The principle used in the analysis of effectiveness appears to have been intention to treat. The clinical outcome measures were time to sedation, pain score, recollection of the event, time from initiation of sedation to time of cardioversion, amount of energy needed for cardioversion, time to return of consciousness, and adverse reactions to the sedatives or anaesthesia. The study groups were comparable in terms of baseline characteristics; except for the fact that there was a significantly greater proportion of in-patients in group 2 (92%) than in group 1 (55%). Effectiveness results The effectiveness results were as follows: Time to sedation was 3 (SD: 2) minutes for group 1 patients compared with 9 (SD: 4) minutes for group 2 patients, (p=0.0001). All patients in both groups were successfully cardioverted to sinus rhythm. Time to return of consciousness was 13 (SD: 6) minutes for group 1 patients and 14 (SD: 8) minutes for group 2 patients, (p=0.56). The mean level of energy necessary for cardioversion to sinus rhythm and the proportion of patients recalling the cardioversion were not significantly different between groups. The one patient in group 2 who recalled being shocked did not perceive the shock as being painful. There was no significant difference in the proportion of patients complaining of nausea. Group 1 patients required 71 (SD: 25) mg of propofol to achieve adequate sedation, whereas group 2 patients required 5 (SD: 2) mg of midazolam plus 4 (SD: 2) mg of morphine sulfate. No patient required intubation in either group. Page: 2 / 5

3 Clinical conclusions This study demonstrated that sedation could be safely administered to patients undergoing elective cardioversion of atrial fibrillation and flutter to sinus rhythm by electrophysiologists certified in administration of conscious sedation. Measure of benefits used in the economic analysis No summary benefit measure was identified in the economic analysis, and only separate clinical outcomes were reported (see effectiveness results above). Direct costs Costs were not discounted due to the short time frame of the cost analysis. Some resource use items were reported separately from the costs and cost items were reported separately. The cost analysis covered the costs of professional services and medications used. The cost data were based on charges. The costs were calculated on an individual basis and were then averaged for the entire group. The price year was Hospital charges for room use and ancillary personnel were the same for the two study groups and were not considered in the cost analysis. Furthermore, it was noted that the extra time required sedating patients with midazolam and morphine compared with propofol was not considered in the cost analysis. Statistical analysis of costs No statistical analysis was carried out. Indirect Costs Indirect costs were not included. Currency US dollars ($). Sensitivity analysis No sensitivity analysis was conducted. Estimated benefits used in the economic analysis See effectiveness results above. Cost results The mean cost incurred in group 1 was $ compared with that in group 2 of $ Synthesis of costs and benefits Not applicable. Authors' conclusions Sedation administered by electrophysiologists for cardioversion of atrial arrhythmia is safe and cost-effective. Midazolam and morphine, the sedative agents administered by electrophysiologists, were effective and well tolerated by patients. CRD COMMENTARY - Selection of comparators Page: 3 / 5

4 A justification was given for the choice of the comparator, which was the traditional procedure used in the setting in question. You, as a database user, should consider whether this is a widely used health technology in your own setting. Validity of estimate of measure of effectiveness The internal validity of the effectiveness results is likely to have been weakened by the non-randomised nature of the study design and the small sample size (as the authors acknowledge). Furthermore, despite the study groups being comparable in terms of most baseline characteristics, there was an important and significant difference between the two groups in terms of the proportion of in-patients, which may have acted as a contributing confounder in the effectiveness outcomes. The degree to which the study sample was representative of the study population cannot be objectively assessed as clear inclusion/exclusion criteria were not reported. No dates were given for the effectiveness data. Validity of estimate of measure of benefit No summary benefit measure was identified in the economic study, and as a result, the study was of cost-consequences design. Validity of estimate of costs The economic study appears to lack a prospective, systematic, and comprehensive evaluation of the resources and unit costs involved in the treatment of patients: some important cost components were not included in the analysis, as acknowledged by the authors. Furthermore, the perspective adopted in the cost analysis was not reported and no investigation was made of the possibility of indirect costs falling to the parties involved in the treatment; charges were used instead of true costs and statistical analysis was not performed on the cost outcomes. However, some quantities and cost units were reported separately; and the price year was given. Other issues The study results need to be treated with some degree of caution due to the limitations of the study design, the lack of sensitivity analysis and systematic cost analysis. The issue of generalisability to other settings or countries was not addressed, although appropriate comparisons were made with other studies. The study sample appears to have been representative of the study population, although this was not discussed in the authors' comments. The authors acknowledged that the cost of extra time required sedating patients with midazolam and morphine compared with propofol was not considered in the cost analysis. However, they believed that, when cardiologists and electrophysiologists have access to propofol, the issue of time to sedation would become more relevant. Alternatively, they believed that, in the age of cost containment, the cost of the anaesthesiologist might be included in the cardioversion procedure, so that the cost is the same with or without the anaesthesiologist present. Implications of the study It was deemed that time to sedation is an important parameter, both from the patient perspective and from the point of view of cost. In this study, time to sedation was shorter when sedation was administered by anaesthesiologists because of the use of propofol. Time to sedation averaged 9 minutes when midazolam and morphine were used versus 3 minutes when propofol was used. However, the authors believed that it is likely that electrophysiologists at their Institution will have access to propofol in the future. Frequently, cardioversions could not be scheduled at a mutually agreeable time for both anaesthesiologist and electrophysiologist; therefore electrophysiologists at the study institution performed cardioversions with conscious sedation. Cost savings came as a by-product of this emerging practice. The authors acknowledged that the sample size was small in this study and believed that it should be expanded in future studies. The authors declared that they do not advocate performing cardioversions without an anaesthetist being close to hand. They believed that one should be available within minutes should the need arise. Source of funding None stated. Page: 4 / 5

5 Powered by TCPDF ( Bibliographic details Goldner B G, Baker J, Accordino A, Sabatino L, DiGiulio M, Kalenderian D, Lin D, Zambrotta V, Stechel J, Maccaro P, Jadonath R. Electrical cardioversion of atrial fibrillation or flutter with conscious sedation in the age of cost containment. American Heart Journal 1998; 136(6): PubMedID Indexing Status Subject indexing assigned by NLM MeSH Aged; Aged, 80 and over; Analgesics, Opioid; Anesthesia Department, Hospital /economics /standards; Anesthesiology; Anesthetics, Intravenous; Atrial Fibrillation /economics /therapy; Atrial Flutter /economics /therapy; Conscious Sedation /economics /methods; Cost Control; Electric Countershock; Electrophysiology; Female; Hospital Charges; Humans; Male; Midazolam; Middle Aged; New York; Propofol AccessionNumber Date bibliographic record published 31/01/2002 Date abstract record published 31/01/2002 Page: 5 / 5