General anaesthesia for external electrical cardioversion of atrial fibrillation: experience of an exclusively cardiological procedural management

Electric Cardioversion in Older Adults. Is Sedation Using Propofol Safe in the Absence of the Direct Anesthetist's Assistance?

Aims: This study aimed to assess the safety of electric cardioversion in the absence of anesthetists assistance. We also evaluated the efficacy and safety of this procedure in older adults (≥80 years) compared to younger populations. Methods: We retrospectively analyzed the data of patients who underwent electric cardioversion at our cardiology department. Patients were divided into 2 groups according to age: ≥ 80 years and <80 years old. Results: The study included 218 participants, 73 were aged 80 years or more (mean age: 84.8 years), and 145 were younger than 80 years (mean age: 66.7 years). Electric cardioversion was effective in 97.3% of older patients and 96.5% of younger patients (P = 1.00). No thromboembolic complications were observed in either of the groups. Asystole >5 s occurred immediately after shock in 4.1% of older and 2.1% of younger patients (P = .405). Propofol was used as a sedative, with a mean dose of 0.83 mg/kg versus 0.93 mg/kg, in older and younger patients, respectively. Intubation, medical intervention, or other advanced resuscitation techniques were not required. During hospitalization, arrhythmia recurred in 9.6% and 12.4% of the older and younger patients, respectively (P = .537). Conclusions: Electrical cardioversion is an effective and safe procedure regardless of patient age. Sedation with propofol administered by cardiologists was safe. Adverse events were not considered serious or reversible.

The Practice of Deep Sedation in Electrophysiology and Cardiac Pacing Laboratories: Results of an Italian Survey Promoted by the AIAC (Italian Association of Arrhythmology and Cardiac Pacing)

The aim of this survey, which was open to all Italian cardiologists involved in arrhythmia, was to assess common practice regarding sedation and analgesia in interventional electrophysiology procedures in Italy. The survey consisted of 28 questions regarding the approach to sedation used for elective direct-current cardioversion (DCC), subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation, atrial fibrillation (AF) ablation, ventricular tachycardia (VT) ablation, and transvenous lead extraction procedures. A total of 105 cardiologists from 92 Italian centres took part in the survey. The rate of centres where DCC, S-ICD implantation, AF ablation, VT ablation and lead extraction procedures were performed without anaesthesiologic assistance was 60.9%, 23.6%, 51.2%, 37.3%, and 66.7%, respectively. When these procedures were performed without anaesthesiologic assistance, the drugs (in addition to local anaesthetics) commonly administered were benzodiazepines (from 64.3% to 79.6%), opioids (from 74.4% to 88.1%), and general anaesthetics (from 7.1% to 30.4%). Twenty-three (21.9%) of the 105 cardiologists declared that they routinely administered propofol, without the supervision of an anaesthesiologist, in at least one of the above-mentioned procedures. In current Italian clinical practice, there is a lack of uniformity in the sedation/analgesia approach used in interventional electrophysiology procedures.

Procedural sedation for direct current cardioversion: a feasibility study between two management strategies in the emergency department

BACKGROUND

A cardiologist-only approach to procedural sedation with midazolam in the setting of elective cardioversion (DCC) for AF has already been proven as safe as sedation with propofol and anaesthesiologist assistance. No data exist regarding the safety of such a strategy during emergency procedures. The aim of this study is to compare the feasibility of sedation with midazolam, administered by a cardiologist, to an anaesthesiologist-assisted protocol with propofol in emergency DCC.

METHODS

Single centre, prospective, open blinded, randomized study including all consecutive patients admitted to the Emergency Department requiring urgent or emergency DCC. Patients were randomized in a 1:1 fashion to either propofol or midazolam treatment arm. Patients in the midazolam group were managed by the cardiologist only, while patients treated with propofol group underwent DCC with anaesthesiologist assistance.

RESULTS

Sixty-nine patients were enrolled and split into two groups. Eighteen patients (26.1%) experienced peri-procedural adverse events (bradycardia, severe hypotension and severe hypoxia), which were similar between the two groups and all successfully managed by the cardiologist. No deaths, stroke or need for invasive ventilation were registered. Patients treated with propofol experienced a greater decrease in systolic and diastolic blood pressure when compared with those treated with midazolam. As the procedure was shorter when midazolam was used, the median cost of urgent/emergency DCC with midazolam was estimated to be 129.0 € (1st-3rd quartiles 114.6-151.6) and 195.6 € (1st-3rd quartiles 147.3-726.7) with propofol (p < .001).

CONCLUSIONS

Procedural sedation with midazolam given by the cardiologist alone was feasible, well-tolerated and cost-effective in emergency DCC.

Safety and efficacy of a cardiologist-only approach to deep sedation for electrical cardioversion

AIMS

Electrical cardioversion is still the preferred method to restore sinus rhythm in patients with atrial fibrillation. The main disadvantage is that electrical cardioversion requires deep sedation, generally administered by anaesthesiologists, for safety concern. An exclusively cardiologic management of deep sedation should have the advantage to reduce resources and time consumed.

METHODS

All consecutive patients admitted to our division with persistent atrial fibrillation or atrial flutter to undergo elective electrical cardioversion from June 2002 to December 2016 were included. The sedation protocol was managed only by cardiologists and involved the administration of a 5-mg bolus of midazolam, followed by increasing doses of propofol to achieve the desired sedation level. Exclusion criteria were strictly observed. Complications were recorded. A retrospective analysis on a deidentified database has been performed.

RESULTS

A total of 1188 electrical cardioversions were scheduled in our centre. A total of 1195 patients were scheduled in our centre, of whom 1188 met inclusion criteria. Electrical cardioversion was performed in 1073 cases (90.3%). Electrical cardioversion was successful in restoring sinus rhythm in 1030 (96.0%) patients. Immediate recurrence of atrial fibrillation occurred in 89 patients (8.3%). 99/1073 (9.22%) patients underwent trans-oesophagel echocardiography before cardioversion. Deep sedation, according to our protocol, was effective in 100% of cases. Midazolam was administered at a dosage of 5 mg to all patients, while propofol was administered at a dosage ranging from 20 to 80 mg (25.1 ± 11.0 mg SD). No anaesthesia-related complications were observed, neither significant respiratory depression requiring intubation nor anaesthesiologist support.

CONCLUSION

The exclusively cardiological procedure of deep sedation seems to be safe and effective.

Effects of propofol sedation on pacing thresholds : Results from an observational cohort study

BACKGROUND

Propofol is one of the most commonly used intravenous anaesthetic drugs for surgical procedures. The use of propofol for sedation is also common practice during endoscopic procedures, electrophysiology studies, and ablation procedures, as well as pacemaker and defibrillator implantation. It was found that propofol alters the electrophysiologic properties of the heart and its conduction system. The effects of propofol on pacing thresholds are unknown and could have implications for pacemaker (PM) and defibrillator (ICD) implantation procedures, as well as sedation and anaesthesia in PM and ICD patients in general.

OBJECTIVES

We sought to investigate the effects of propofol sedation on atrial and right ventricular pacing thresholds in PM and ICD patients.

MATERIALS AND METHODS

A total of 50 patients with PM, ICD, or cardiac resynchronization therapy (CRT) undergoing propofol sedation for electrophysiology (EP) investigation, transesophageal echocardiography (TEE), electrocardioversion (ECV), or bronchoscopy were included prospectively. Pacing thresholds, impedance, and sensing were assessed by device interrogation immediately prior to sedation and after the desired sedation depth was achieved by the administration of propofol.

RESULTS

Mean atrial (0.68 V vs 0.77 V, p = 0.136) and mean right ventricular thresholds (0.90 V vs 0.93 V, p = 0.274) remained unchanged. Impedances and sensing remained unaffected in all patients.

CONCLUSIONS

Propofol sedation did not affect pacing thresholds of atrial and right ventricular leads in this cohort of PM and ICD patients.

Cardioversion: What to choose? Etomidate or propofol

Context:

Electrical cardioversion is a short painful procedure to regain normal sinus rhythm requiring anaesthesia for haemodynamic stability, sedation, analgesia and early recovery.

Aims:

To compare propofol and etomidate as sedatives during cardioversion.

Settings and Design:

Single centred, prospective and randomized single blind study comprising 60 patients.

Subjects and Methods:

Patients more than 18 years, American Society of Anesthesiologists I/II/III grades undergoing elective cardioversion, randomly divided to receive propofol 1 mg/kg intravenous (IV) bolus followed by 0.5 mg/kg (Group P, n = 30) or etomidate (Group E, n = 30) 0.1 mg/kg followed by 0.05 mg/kg. All patients received IV fentanyl (1 μg/kg) before procedure. Heart rate, blood pressure (BP) (systolic BP [SBP], diastolic BP [DBP], mean arterial pressure), respiratory rate, Aldrete recovery score (ARS) and Ramsay sedation score (RSS) were assessed at 1, 2, 5, 10, 15, 20 and 30 min post cardioversion. Incidence of hypotension, respiratory depression and side effects were compared.

Statistical analysis used:

Student's unpaired t-test, Chi-square test and Mann–Whitney test. P < 0.05 was taken as significant.

Results:

Group P showed significant fall in SBP, DBP, and mean BP at 2 min after cardioversion. Hypotension (33.3% Group P vs. 16.65% Group E) occurred more with propofol (P < 0.05). Group E showed better ARS at 1, 2, 5, 10, 15 and 20 min. Time required to attain RSS = 2 (659.1 s Group P and 435.7 s Group E) indicated longer recovery with propofol. Left atrial size (35.5-42.5 mm) did not affect success rate of cardioversion (80% Group P vs. 83.3% Group E). Incidence of myoclonus (Group E 26.67% vs. Group P 0%) showed significant difference.

Conclusions:

Etomidate/fentanyl is superior over propofol/fentanyl during cardioversion for quick recovery and haemodynamic stability.

Inhibition of cardiac Kv1.5 potassium current by the anesthetic midazolam: mode of action

Midazolam is a short-acting benzodiazepine that is widely used in anesthesia. Despite its widespread clinical use, detailed information about cardiac side effects of midazolam is largely lacking. Using the double-electrode voltage clamp technique, we studied pharmacological effects of midazolam on heterologously expressed Kv1.5 channels underlying atrial repolarizing current I(Kur). Midazolam dose-dependently inhibited Kv1.5 current, yielding an IC50 of 17 μM in an HEK cell line and an IC50 of 104 μM in Xenopus oocytes. We further showed that midazolam did not affect the half-maximal activation voltage of Kv1.5 channels. However, a small negative shift of the inactivation curve could be observed. Midazolam acted as a typical open-channel inhibitor with rapid onset of block and without frequency dependence of block. Taken together, midazolam is an open channel inhibitor of cardiac Kv1.5 channels. These data add to the current understanding of the pharmacological profile of midazolam.

Sedation for electrophysiological procedures

Administration of intravenous sedation (IVS) has become an integral component of procedural cardiac electrophysiology. IVS is employed in diagnostic and ablation procedures for transcutaneous treatment of cardiac arrhythmias, electrical cardioversion of arrhythmias, and the insertion of implantable electronic devices including pacemakers, defibrillators, and loop recorders. Sedation is frequently performed by nursing staff under the supervision of the proceduralist and in the absence of specialist anesthesiologists. The sedation requirements vary depending on the nature of the procedure. A wide range of sedation techniques have been reported with sedation from the near fully conscious to levels approaching that of general anesthesia. This review examines the methods employed and outcomes associated with reported sedation techniques. There is a large experience with the combination of benzodiazepines and narcotics. These drugs have a broad therapeutic range and the advantage of readily available reversal agents. More recently, the use of propofol without serious adverse events has been reported. The results provide a guide regarding the expected outcomes of these approaches. The complication rate and need for emergency assistance is low in reported series where sedation is administered by nonspecialist anesthesiology staff.

Ibutilide for the Cardioversion of Paroxysmal Atrial Fibrillation during Radiofrequency Ablation of Supraventricular Tachycardias

Direct current electrical cardioversion (DC-ECV) is the preferred treatment for the termination of paroxysmal atrial fibrillation (AF) that occurs during radiofrequency ablation (RFA) of supraventricular tachycardias (SVT). Intravenous Ibutilide may be an alternative option in this setting. Thirty-four out of 386 patients who underwent SVT-RFA presented paroxysmal AF during the procedure and were randomized into receiving ibutilide or DC-ECV. Ibutilide infusion successfully cardioverted 16 out of 17 patients (94%) within 17.37 ± 7.87  min. DC-ECV was successful in all patients (100%) within 17.29 ± 3.04  min. Efficacy and total time to cardioversion did not differ between the study groups. No adverse events were observed. RFA was successfully performed in 16 patients (94%) in the ibutilide arm and in all patients (100%) in the DC-ECV arm, p = NS. In conclusion, ibutilide is a safe and effective alternative treatment for restoring sinus rhythm in cases of paroxysmal AF complicating SVT-RFA.