Intraoperative torsade de pointes ventricular tachycardia and ventricular fibrillation during sevoflurane anesthesia

Nonsustained ventricular tachycardia during outpatient anesthesia: a case report

During the perioperative period, anesthesiologists frequently observe cardiac tachyarrhythmia. Ventricular tachycardia is very rare in non-cardiac surgeries. However, it can be fatal when it occurs. Therefore, anesthesiologists should be watchful so as to not to miss ventricular tachycardia and take the appropriate steps to manage it promptly. We present a case, with a review of related literature, in which a non-sustained ventricular tachycardia was observed in a patient who visited the hospital for dental treatment.

Concealed congenital long QT syndrome during velopharyngeal dysfunction correction: a case report

The congenital long QT syndrome (LQTS) is an inherited cardiac disorder characterized by increased QT intervals and a tendency to experience ventricular tachycardia, which can cause fainting, heart failure, or sudden death. A 4-year-old female patient undergoing velopharyngeal correction surgery under general anesthesia suddenly developed Torsades de pointes. Although the patient spontaneously resolved to sinus rhythm without treatment, subsequent QT prolongation persisted. Here, we report a case of concealed LQTS with a literature review.

Comparison of the Effects of Propofol and Sevoflurane on QT Interval in Pediatrics Undergoing Cochlear Implantation: A Randomized Clinical Trial Study

Background

Children with sensorineural hearing loss are at risk of cardiac electrophysiologic abnormalities. Inhalational Sevoflurane induction in these children can cause QT prolongation.

Objectives

In order to evaluate the safety of inhalational induction of anesthesia with sevoflurane in children with sensorineural hearing loss, who are candidates for cochlear implant, its electrophysiologic effects was compared with intravenous induction of anesthesia with propofol.

Methods

In this double-blind randomized clinical trial, 61 children aged between one and eighteen years old, who were candidates for cochlear implantation, were randomly allocated to groups receiving anesthesia with sevoflurane (n = 32) or propofol (n = 29) for induction of anesthesia. Two 12-leads ECG were taken from all of patients before and after induction and QTc, Tp-e interval, and JTc were measured and compared.

Results

Two cases, who had pre-induction QTc longer than 500 ms were excluded from the study. Patients had similar age (102.58 ± 87 versus 101.46 ± 67 months, P = 0.95) and gender (males: 48.3% versus 56.3%, P = 0.53) distribution. The researchers observed significant post induction difference in QTc values between these groups (propofol 422.5 ± 40, sevoflurane 445.0 ± 29, P = 0.016). There was no significant difference in the percent QTc and Tp-e changes in propofol and sevoflurane groups. Greater percentage of patients with increased Tp-e interval (> 100 ms) in the sevoflurane group than the propofol group was also seen. There was no significant long QTc difference (QTc > 500 ms or more than 60 ms increase from baseline) after induction of anesthesia in the sevoflurane group compared to the propofol group (15.6% versus 13.8%, P = 0.84).

Conclusions

After electrophysiological evaluations in children with sensorineural hearing loss, in patients whose pre-induction QTc is not longer than 500 ms, propofol seems safer than inhalational sevoflurane for induction of anesthesia.

Pulseless Ventricular Tachycardia During Office-Based Anesthetic in a Four-Year-Old Child

A 4-year-old 16-kg boy presented for full mouth dental rehabilitation in a private pediatric dental office. The patient had no significant previous medical history. Upon sevoflurane induction by a dentist anesthesiologist, the patient converted from normal sinus rhythm to pulseless ventricular tachycardia. Advanced cardiac life support protocol was initiated. After 2 automatic external defibrillator shocks were delivered in conjunction with epinephrine administration, the patient returned to normal sinus rhythm. The patient was transported via emergency medical service paramedics to a local children's hospital emergency room where he was observed uneventfully for 24 hours prior to discharge.

[Perioperative treatment of patients with long QT syndrome]

Long QT syndrome (LQTS) is caused by a change in cardiac repolarization due to functional ion channel dysfunction which is associated with an elongation of the QT interval (hence the name) in the electrocardiogram and a predisposition to cardiac rhythm disorders (e.g. torsade de pointes, TdP) as well as cardiac events up to sudden cardiac death. There is a congenital (cLQTS) and an acquired (aLQTS) form of the disease. The prevalence of cLQTS is 1 in 2000 but aLQTS is much more common and includes a grey area due to many asymptomatic patients. The LQTS is, therefore, more common than malignant hyperthermia which is much discussed in anesthesiology and has a reported prevalence in the population of 1:3000. Considering the prevalence of both aLQTS as well as cLQTS the importance of the LQTS seems to be underestimated in current perioperative care. Potential perioperative risks of such patients can be significantly reduced by appropriate patient management. This includes adequate preoperative preparation, the correct choice of anesthetic medication as well as adequate perioperative monitoring and preparedness for immediate pharmaceutical and electrical intervention in case of typical cardiac rhythm disturbances, such as TdP arrhythmia.

The clinical significance of QT interval prolongation in anesthesia and pain management: what you should and should not worry about

The most feared drug-induced complication is fatal cardiac arrest. Torsades de pointes (TdP) is a polymorphic ventricular tachycardia occurring in the setting of a QT interval prolongation and is the most frequent type of drug-induced pro-arrhythmia. The most common mechanism of QT prolongation and TdP is blockade of the rapid component of the delayed rectifier repolarizing potassium conductance IKr. Anesthesiologists have extensive experience with QT prolonging drugs, but there are relatively few reports of TdP occurring in the perioperative setting. Nevertheless, regulatory concern regarding the drug droperidol resulted in a significant reduction in its use. Concern regarding two other agents that potently block IKr, i.e., sevoflurane and methadone, has grown, and practitioners are worried that these valuable agents may meet the same fate. In this review, the data regarding the TdP risk of droperidol, sevoflurane, and methadone are compared with particular emphasis on the different settings in which they are employed. While the three drugs are potent IKr inhibitors, little evidence exists to suggest that droperidol or sevoflurane are associated with significant proarrhythmia in the perioperative setting. Due to factors such as inhibition of the parasympathetic nervous system, prevention of hypoxia and hypercarbia, and attention to serum electrolytes, TdP is a very rare occurrence in the perioperative environment. Methadone, however, is typically given to outpatients, over long periods, and in combination with agents that inhibit its metabolism or are QT prolonging in their own right. Thus, pre- and post-drug electrocardiograms may be appropriate when prescribing methadone for outpatients, while the much lower risk for TdP (and the difficulties inherent in QT measurement in the perioperative period) render this approach unfruitful and worthy of reevaluation.

Unusual diagnosis of a persistent third-degree atrioventricular block during anesthesia in a "healthy" pediatric patient

We present an unusual diagnosis of a permanent third-degree atrioventricular block under general anesthesia in an otherwise healthy and asymptomatic child. This diagnosis of unclear causality represented a serious rare finding, requiring judicious management and resulting in the placement of a permanent pacemaker.

Sevoflurane-induced arrhythmia in an adult and a child

When inhalational induction is indicated, sevoflurane is the most popular choice in both children and adults. Higher inspired concentrations of sevoflurane can cause adverse cardiac arrhythmias that are seen to disappear once the agent is discontinued. We report the occurrence of isorhythmic atrioventricular dissociation and junctional rhythm with absent P waves during sevoflurane anaesthesia in an adult and a child, respectively.