MANAGEMENT OF PAROXYSMAL ATRIOVENTRICULAR NODAL REENTRANT TACHYCARDIAIN THE CRITICALLY ILL SURGICAL PATIENT

Objectives: Paroxysmal atrioventricular nodal reentrant tachycardia is an infrequently encountered supraventricular arrhythmia that continue s to present difficult management problems in the critically ill surgi cal patient. The purpose of this study was to evaluate the efficacy of a new treatment algorithm involving the sequential administration of different classes of antiarrhythmic agents until conversion to sinus r hythm was achieved. Design: Nonrandomized, consecutive, protocol-drive n descriptive cohort. Setting: University hospital surgical and trauma intensive care unit (ICU). Patients: During an 11-month period, we pr ospectively evaluated all hemodynamically stable patients who sustaine d new-onset atrioventricular nodal reentrant tachycardia. Intervention s: Vagal maneuver, followed by the rapid, sequential infusion of antia rrhythmic agents (i.e., adenosine, verapamil, and esmolol, respectivel y) until the arrhythmia was terminated. Measurements and Main Results: Twenty-seven patients (4% of all admissions) were evaluated, includin g 16 trauma patients (Injury Severity Score of 20 +/- 8) and 11 genera l surgical patients (Acute Physiology and Chronic Health Evaluation II score of 17 +/- 7). Time from ICU admission to onset of atrioventricu lar nodal reentrant tachycardia was 4.5 +/- 5 days (median 2.5). Arrhy thmia termination was achieved in all patients within minutes (mean 13 +/- 10 [so]). Incremental sequential adenosine administration alone, however, was successful in effecting conversion to sinus rhythm in onl y 44% of initial episodes of atrioventricular nodal reentrant tachycar dia (95% confidence interval 21% to 67%). A total of 14 (52%) patients developed 38 relapses of paroxysmal supraventricular tachycardia in t he ICU after initial conversion to sinus rhythm. These relapses requir ed additional antiarrhythmic therapy. Adenosine was only effective in 34% of the relapses (95% confidence interval 17% to 53%). Seven (50%) of these 14 patients developed multiple relapses, However, only two pa tients were receiving suppressive calcium-channel or beta-adrenergic r eceptor blockade at the time of relapse. Conclusions: The use of a mul tiagent algorithm was effective for the initial conversion of new-onse t atrioventricular nodal reentrant tachycardia to sinus rhythm in crit ically ill surgical and trauma patients. This preliminary report sugge sts that adenosine has marginal efficacy in the critically ill surgica l or trauma patient. Given the high frequency of relapses, regardless of the agents used to achieve initial control, suppression therapy for the arrhythmia during the period of maximal cardiovascular stress is essential.