An assessment of desflurane for use during cardiac electrophysiological study and radiofrequency ablation of supraventricular dysrhythmias in children

Anaesthetic management of paediatric patients undergoing electrophysiology study and ablation for supraventricular tachycardia: A focused narrative review

Every year, 80,000-100,000 ablation procedures take place in the United States and approximately 1% of these involve paediatric patients. As the paediatric population undergoing catheter ablation to treat dysrhythmia is constantly growing, involvement of anaesthesiologists in the cardiac electrophysiology laboratory is simultaneously increasing. Compared with the adult population, paediatric patients need deeper sedation or general anaesthesia (GA) to guarantee motionlessness and preserve comfort. As a result, the anaesthesiologist working in this setting should keep in mind heart physiopathology as well as possible interactions between anaesthetic drugs and arrhythmia. In fact, drug-induced suppression of accessory pathways (APs) conduction capacity is a major concern for completing a successful electrophysiology study (EPS). Nevertheless, the literature on this topic is scarce and the optimal type of anaesthesia in EPS and ablation procedures in children is still controversial. Thus, the main goal of the present review is to collect the literature published so far on the effects on cardiac conduction tissue of the drugs commonly employed for sedation/GA in the cath lab for EPS and ablation procedures to treat supraventricular tachycardia in patients aged <18 years.

Anesthetic Management In Electrophysiology Laboratory: A Multidisciplinary Review

Many clinical challenges have been encountered in electrophysiology laboratories (EP) while implanting intracardiac defibrillators for lethal arrhythmias, using pacemakers for bradyarrhythmias, placing pacemakers with multiple leads in patients with heart failure and cardiac ablation procedures. In this environment, anesthesiology plays a very critical role to ensure patients comfort, as well as maintains operator's convenience and facilitate management of undesired situations. EP laboratories are mostly used for diagnosis of certain heart diseases. Meanwhile, with the exponential increase in interventional procedures in our decade, electrophysiologists' need to cooperate with the anesthesiologists more frequently. The literature is still unclear about the effects of anesthetic agents on cardiac conduction pathways, but as we know with our previous data, the most agents we are using currently have more or less effect on the cardiac conduction systems. In this review, we aimed to describe the safe anesthesia methods in cardiac diagnostic procedures and have a closer look up the anesthetic outcomes of these procedures. This article comprehensively reviews the anesthesia practice encountered in electrophysiology laboratories.

Electrophysiological effects of desflurane in children with Wolff-Parkinson-White syndrome: a randomized crossover study

BACKGROUND

We hypothesized that, compared with propofol, desflurane prolongs the antegrade accessory pathway effective refractory period (APERP) in children undergoing radiofrequency catheter ablation for Wolff-Parkinson-White (WPW) syndrome.

METHODS

In this randomized crossover study, children aged 4.1-16.1 years undergoing radiofrequency catheter ablation for WPW syndrome were randomly divided into four groups according to the concentration of desflurane and anesthetics used in the first and the second electrophysiological studies (EPS). After induction of general anesthesia with propofol and tracheal intubation, they received one of the following regimens: 0.5 minimum alveolar concentration (MAC) desflurane (first EPS) and propofol (second EPS) (Des0.5-Prop group, n = 8); propofol (first EPS) and 0.5 MAC desflurane (second EPS) (Prop-Des0.5 group, n = 9); 1 MAC desflurane (first EPS) and propofol (second EPS) (Des1.0-Prop group, n = 10); propofol (first EPS) and 1 MAC desflurane (second EPS) (Prop-Des1.0 group, n = 9). Radiofrequency catheter ablation was performed upon completion of EPS. Sample size was determined to detect a difference in the APERP.

RESULTS

Desflurane at 1.0 MAC significantly prolonged the APERP compared with propofol, but did not affect the sinoatrial conduction time, atrio-His interval or atrioventricular node effective refractory period. Supraventricular tachycardia was induced in all children receiving propofol, but not induced in 1 and 4 children receiving 0.5 MAC and 1.0 MAC desflurane, respectively.

CONCLUSION

Desflurane enhances the refractoriness and may block the electrical conduction of the atrioventricular accessory pathway, and is therefore not suitable for use in children undergoing radiofrequency catheter ablation for WPW syndrome.

Anesthetic Drugs in Congenital Heart Disease

The structural defects associated with the various forms of congenital heart disease lead to pathological and functional changes that place patients at risk for adverse events, and in fact the perioperative incidence of morbidity and mortality has been documented to be increased in children with congenital heart disease. Patients with congenital heart disease can present to the anesthesiologist in a relatively precarious state of balance of several hemodynamic factors, including preload, ventricular contractility, systemic vascular resistance, pulmonary vascular resistance, heart rate, and cardiac rhythm. Anesthetic drugs can affect each of these, and an ideal anesthetic drug for such patients does not exist. The purpose of this article is to review the hemodynamic effects of anesthetic drugs and how they may contribute to the occurrence of adverse events in children with congenital heart disease.

Anesthesia for Electrophysiology Studies and Catheter Ablations

Providing anesthesia in nonoperating room locations is becoming increasingly common. The field of electrophysiology and its patient population are growing, resulting in a greater need for anesthesiologists in the electrophysiology laboratory. The procedures are complex and of long duration with patients who have multiple comorbidities. The electrophysiology laboratory is a unique situation in that arrhythmias are sought and sometimes even provoked so that they may be eliminated. The focus of this review will be on anesthesia for electrophysiology studies and catheter ablation.

The anaesthetist and the cardiac catheterisation laboratory

Interventional cardiology is an innovative and expanding field. Anaesthetists are increasingly involved in managing complex congenital and acquired heart lesions in the cardiac catheterisation laboratory. This article provides an overview of common lesions encountered in the cardiac catheterisation laboratory, the anaesthetic management of patients with congenital and acquired heart lesions, the procedures performed and the complications encountered during such procedures.

Anaesthesia for children with congenital heart disease undergoing diagnostic and interventional procedures

PURPOSE OF REVIEW

Anaesthesiologists are often asked to administer sedation and anaesthesia to infants and children with congenital heart disease undergoing diagnostic and interventional procedures. A number of issues are pertinent to a safe and effective provision of care for these patients. The anaesthetic should ensure haemodynamic stability, provide real-life circumstances to ensure diagnostic accuracy, should be easy and reliable to titrate in order to cope with rapidly changing loading conditions and intense but short-lived haemodynamic disturbances. The anaesthetic drugs should not interfere with electrophysiological processes in the cardiac conduction system, and above all anaesthetic recovery should be swift and devoid of side-effects.

RECENT FINDINGS

In recent years, new agents have been introduced in the anaesthetic care of these patients. One has studied the haemodynamic and electrophysiological properties of agents such as remifentanil, desflurane, sevoflurane and propofol and their use in children with congenital heart disease. New and older drugs have been combined in balanced techniques to decrease the side-effects associated with monotherapy. Besides these anaesthetic concerns, the controversy about the presence of an anaesthesiologist versus a non-anaesthesiologist still continues.

SUMMARY

The newer anaesthetic agents, such as desflurane, remifentanil, sevoflurane and propofol are an integral part of our armamentarium to care for children with congenital heart disease. The combination of these and older drugs allow us to provide anaesthetic care in an effective and efficient way.

Flumazenil is innocuous in a paroxysmal supraventricular tachycardia and radiofrequency ablation: a paediatric case report and review of the literature

The efficacy and safety of flumazenil in reversing midazolam-induced paradoxical reaction in a child suffering from paroxysmal supraventricular tachycardia (PSVT) and undergoing radiofrequency ablation procedure has not been described before. We report a boy who had suffered for years from poorly controlled PSVT because of noncompliance to medications and was being sedated by midazolam and morphine (4 mg each) and prepared for radiofrequency ablation when he began attempting to speak, writhing and flailing his arms, for which physical restraint was required. We also review the current knowledge on the subject. Two doses of flumazenil 0.05 mg i.v. swiftly halted the untoward episode. The child opened his eyes and was calm, coherent and able to answer simple questions. All haemodynamic and respiratory parameters remained stable throughout this event, except for a temporary increase in heart rate (from 68 to 83 b x min-1). The aberrant behaviour did not resume when he was allowed to fall asleep during the ablation of a concealed left lateral accessory pathway. After that procedure, he awoke calm and pain free with no recollection of the aggressive episode. He was kept for 24 h in an intermediate cardiac care unit and was then discharged home. This apparent first report on the efficacious use of flumazenil for the reversal of a paradoxical reaction to midazolam during an electrophysiological study suggests that it neither induces abnormal heart rate nor interferes with the electrophysiological study or the ablation procedure.

Management of paediatric patients undergoing diagnostic and invasive cardiology procedures

Since diagnostic cardiac catheterization in children with congenital heart disease was first reported in 1947, echocardiography has been used as a non-invasive diagnostic tool in congenital heart disease, resulting in a decrease in diagnostic cardiac catheterizations. However, the total number of cardiac catheterizations remained at a steady level until the mid-1980s and has since increased progressively. This is a result of the introduction of interventional transcatheter techniques to improve or correct congenital heart malformations. Since the first description of balloon atrial septostomy, the range of indications for such techniques has steadily increased, particularly in the past 15 years. 'Deep' sedation or general anaesthesia is essential for the conduct of cardiac catheterization in children, particularly in the younger age group.