Single-syringe Administration of Diluted Adenosine

Keeping It "Current": A Review of Treatment Options for the Management of Supraventricular Tachycardia

OBJECTIVE

To review treatment options and updates that exist for the management of paroxysmal supraventricular tachycardia (PSVT).

DATA SOURCES

A literature search of PubMed was performed including articles from 1974 to June 2023 using the terms: arrhythmias, adenosine, verapamil, diltiazem, esmolol, propranolol, metoprolol, beta-blockers, amiodarone, PSVT, synchronized cardioversion, methylxanthines, dipyridamole, pediatrics, heart transplant, and pregnancy. Primary literature and guidelines were reviewed.

STUDY SELECTION AND DATA EXTRACTION

Studies were considered if they were available in English and conducted in humans.

DATA SYNTHESIS

PSVT is a subset of supraventricular tachycardia (SVT) that presents as a rapid, regular tachycardia with an abrupt onset and termination. Due to frequent emergency department (ED) visits annually with symptoms of PSVT, appropriate and efficient management of these patients is vital. This review provides an overview of the pathophysiology of PSVT, while also describing the literature behind nonpharmacologic and pharmacologic management of PSVT.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review describes new literature regarding the improved success of the modified Valsalva maneuver as a nonpharmacologic therapy in PSVT. In addition, it describes a new technique in administration of adenosine that has improved outcomes, defines dose adjustments needed for drug interactions with adenosine, compares the utilization of nondihydropyridine calcium channel blockers with adenosine, and provides management recommendations for patients in special populations.

CONCLUSIONS

With high annual rates of ED visits for SVT, providers should be aware of the data behind management and modifications of therapy based on patient-specific factors (ie, patient preference, pharmacokinetics/pharmacodynamics, drug interactions, and special populations).

Pathophysiology and treatment of adults with arrhythmias in the emergency department, part 1: Atrial arrhythmias

PURPOSE

This article, the first in a 2-part review, aims to reinforce current literature on the pathophysiology of cardiac arrhythmias and various evidence-based treatment approaches and clinical considerations in the acute care setting. Part 1 of this series focuses on atrial arrhythmias.

SUMMARY

Arrhythmias are prevalent throughout the world and a common presenting condition in the emergency department (ED) setting. Atrial fibrillation (AF) is the most common arrhythmia worldwide and expected to increase in prevalence. Treatment approaches have evolved over time with advances in catheter-directed ablation. Based on historic trials, heart rate control has been the long-standing accepted outpatient treatment modality for AF, but the use of antiarrhythmics is often still indicated for AF in the acute setting, and ED pharmacists should be prepared and poised to help in AF management. Other atrial arrhythmias include atrial flutter (AFL), atrioventricular nodal reentry tachycardia (AVNRT), and atrioventricular reentrant tachycardia (AVRT), which warrant distinction due to their unique pathophysiology and because each requires a different approach to utilization of antiarrhythmics. Atrial arrhythmias are typically associated with greater hemodynamic stability than ventricular arrhythmias but still require nuanced management according to patient subset and risk factors. Since antiarrhythmics can also be proarrhythmic, they may destabilize the patient due to adverse effects, many of which are the focus of black-box label warnings that can be overreaching and limit treatment options. Electrical cardioversion for atrial arrhythmias is generally successful and, depending on the setting and/or hemodynamics, often indicated.

CONCLUSION

Atrial arrhythmias arise from a variety of mechanisms, and appropriate treatment depends on various factors. A firm understanding of physiological and pharmacological concepts serves as a foundation for exploring evidence supporting agents, indications, and adverse effects in order to provide appropriate care for patients.

The Single-Syringe Versus the Double-Syringe Techniques of Adenosine Administration for Supraventricular Tachycardia: A Systematic Review and Meta-Analysis

INTRODUCTION

The intravenous double-syringe technique (DST) of adenosine administration is the first-line treatment for stable supraventricular tachycardia (SVT). Alternatively, the single-syringe technique (SST) was recently found to be potentially beneficial in several studies. This study aimed to perform a meta-analysis of the SST versus the DST of adenosine administration for the treatment of SVT.

METHODS

We assessed EMBASE, PubMed, Cochrane, and ClinicalTrials.gov databases for randomized controlled trials (RCTs) and non-randomized studies of intervention (NRSIs) comparing the DST to the SST of adenosine administration in patients with SVT. Outcomes included termination rate, termination rate at first dose, total administered dose, adverse effects, and discharge rate.

RESULTS

We included four studies (three RCTs and one NRSI) with a total of 178 patients, of whom 99 underwent the SST of adenosine administration. No significant difference was found between treatment groups regarding termination rate, termination rate restricted to RCTs, total administered dose, and discharge rate. Termination rate at first dose (odds ratio 2.87; confidence interval 1.11-7.41; p = 0.03; I² = 0%) was significantly increased in patients who received the SST. Major adverse effects were observed in only one study.

CONCLUSIONS

The SST is probably as safe as the DST and at least as effective for SVT termination, SVT termination at first dose, and discharge rate from the emergency department. However, definitive superiority of one technique is not feasible given the limited sample size.

REGISTRATION

PROSPERO identifier nº CRD42022345125.

Comparison of sinus conversion rates and body weights after 6 mg adenosine administration in supraventricular tachycardia

BACKGROUND

To evaluate the relationship between body weight and the success rate of supraventricular tachycardia (SVT) termination after an initial 6-mg adenosine administration.

METHODS

This retrospective observational study was conducted with medical records of patients who visited a single tertiary emergency department and underwent an electrophysiologic study with an SVT diagnosis. Patients under 18 years of age or those with SVT aberrancy, recurring SVT after radiofrequency catheter ablation, premedication of non-dihydropyridine calcium channel blocker, and signs of shock were excluded.

RESULTS

Data from 124 patients were collected. There were 69 women (55.6%); mean age, 49.7 years. The mean weight and height were 66.8 kg and 164.8 cm, respectively. Adenosine dose was 0.09 mg/kg. For the first sinus conversion (SC) success group (83 patients, 67%), the mean weight, height, and adenosine dose were 61.0 ± 11.5 kg, 161.9 ± 8.1 cm, and 0.10 ± 0.02 mg/kg. For the first SC failure group, these values were 78.4 ± 17.0 kg, 170.7 ± 8.9 cm, and 0.079 ± 0.02 mg/kg, respectively. To evaluate factors associated with the first SC, we performed bivariate logistic regression with weight (odds ratio [OR]: 1.093; 95% confidence interval [CI]: 1.045-1.144; P < 0.001) and height (OR: 1.071; 95% CI: 1.008-1.138; P = 0.027). Receiver operating characteristics curves and the cut-off values for adenosine dose and weight were 0.90 mg/kg and 66.5 kg with 71.1% sensitivity and 73.2% specificity (area under the curve: 0.814; 95% CI: 0.73-0.90; P < 0.001).

CONCLUSION

Weight and height were significant predictors of the first SC success rate among SVT patients. Consequentially, it is necessary to consider other adenosine administration methods, including increasing the initial drug dose or changing the flushing strategy after adenosine injection.

An Evaluation of Prehospital Adenosine Use

BACKGROUND

Adenosine has been safely used by paramedics for the treatment of stable supraventricular tachycardia since the mid-1990s. However, there continues to be variability in paramedics' ability to identify appropriate indications for adenosine administration. As the first of a planned series of studies aimed at improving the accuracy of SVT diagnosis and successful administration of adenosine by paramedics, this study details the current usage patterns of adenosine by paramedics.

METHODS

This cross-sectional retrospective study investigated adenosine use within a large northeast EMS region from January 1, 2019, through September 30, 2021. Excluding pediatric and duplicate case reports, we created a dataset containing patient age, sex, and vital signs before, during, and after adenosine administration; intravenous line location; and coded medical history from paramedic narrative documentation, including a history of atrial fibrillation, suspected arrhythmia diagnosis, and effect of adenosine. In cases with available prehospital electrocardiograms (EKGs) for review, two physicians independently coded the arrhythmia diagnosis and outcome of adenosine administration. Statistical analysis included interrater reliability with Cohen's kappa statistic.

RESULTS

One hundred eighty-three cases were included for final analysis, 84 did not have a documented EKG for review. Categorization of presenting rhythms in these cases occurred by a physician reviewing EMS narrative and documentation. Forty of these 84 cases (48%) were adjudicated as SVT likely, 32 (38%) as SVT unlikely and 12 (14%) as uncategorized due to lack of supporting documentation. Of the 99 cases with EKGs available to review, there was substantial agreement of arrhythmia diagnosis interpretation between physician reviewers (Cohen's kappa 0.77-1.0); 54 cases were adjudicated as SVT by two physician reviewers. Other identified cardiac rhythms included atrial fibrillation (16), sinus tachycardia (11), and ventricular tachycardia (2). Adenosine cardioversion occurred in 47 of the 99 cases with EKGs available for physician review (47.5%). Adenosine cardioversion was also deemed to occur in 87% (47/54) of cases when the EKG rhythm was physician adjudicated SVT.

CONCLUSIONS

This study supports the use of adenosine as a prehospital treatment for SVT while highlighting the need for continued efforts to improve paramedics' identification and management of tachyarrhythmias.

Comparison between the double-syringe and the single-syringe techniques of adenosine administration for terminating supraventricular tachycardia: A pilot, randomized controlled trial

BACKGROUND

Adenosine has been recommended as a first-line treatment for stable supraventricular tachycardia (SVT). Standard guidelines recommend 6-mg of adenosine administered intravenously (IV) with an immediate 20-ml IV bolus of normal saline solution (NSS; double syringe technique [DST]). However, a newly proposed single-syringe technique (SST), in which adenosine is diluted with an up to 20 ml IV bolus of NSS, was found to be beneficial.

HYPOTHESIS

We hypothesized that the SST was noninferior to the DST for terminating stable SVT.

METHODS

A pilot multicenter, single-blind, randomized controlled study was conducted at nine hospitals in north and northeast Thailand. Thirty patients who were diagnosed with stable SVT were randomized into two groups of 15, with one receiving adenosine via the DST and the other via the SST. We examined SVT termination, the average successful dose, and the complication rate of each group. Analyses were based on the intention-to-treat principle.

RESULT

The termination rate was 93.3% in the DST and 100% in the SST group (p = 1.000), and the success rate of the first 6-mg dose of adenosine was 73.3% and 80%, respectively (p = 1.000). The total administered dose was 8.6 ± 5.1 mg in the DST group and 7.6 ± 4.5 mg in the SST group (p = .608). No complications were found in either group.

CONCLUSIONS

The SST was non-inferior to the DST for termination of SVT. However, a further definitive study with a larger sample size is required.

A Case Report of Neonatal Supraventricular Tachycardia Resolved with Single-Syringe Adenosine

Introduction

Supraventricular tachycardia (SVT) is a condition requiring emergency care in neonates.

Case Report

We describe a successfully treated case of neonatal SVT in a four-week-old neonate using the novel adenosine administration method. This technique is potentially easier to facilitate and does not require equipment such as a stopcock. Adenosine 0.2 milligrams per kilogram was drawn up into a syringe containing 0.9% sodium chloride to a total volume of 3 milliliters. Once administered, the patient had near-immediate return to normal sinus rhythm without sequelae.

Conclusion

This case demonstrates that the single-syringe method appears potentially safe and effective in neonates.