Home About SPA Join SPA Education Newsletter Jobs & Fellowships Volunteer Service Abroad Links of Interest

SPA Newsletter

.

Chiang V, Burns J, Rifai N et al. Journal of Pediatrics 2000;137:73-77

This paper reports on 29 patients who received IV terbutaline as treatment for severe asthma in whom evidence of myocardial damage was sought. Measures of cardiac toxicity were cardiac troponin (cTnT) and comparison of cTnT with creatine kinase (CK), creatine kinase MB (CK-MB) and ECG changes. Terbutaline was administered as follows: a loading dose of 10 mcg/kg was given over 10 minutes followed by 0.4 mcg/kg/min. the infusion was increased by 0.2 mcg/kg/min increments titrated to therapeutic effect or until tachycardia, tremulousness or anxiety were noted. cTnT appears to be both a specific and sensitive indicator of cardiac damage and higher levels have been associated with increased mortality. The mean age of the patients in the study was 9 +/- 6 years and there were 12 males. The mean duration of terbutaline infusion was 55 +/- 50 hours and the mean maximum dose of terbutaline was 2.4 mcg/kg/min.

Three patients (10%) had detectable cTnT levels and the levels were minimal, well below the levels associated with myocardial ischemia. These three patients underwent mechanical ventilation for the longest period of time and received significantly longer terbutaline infusion than the other patients (126 hours vs. 45 hours). No clinically significant cardiac toxicity was noted in the patients who received terbutaline infusions. The authors conclude that terbutaline infusion given to patients with severs asthma is not associated with significant cardiac toxicity.

Comment: Intra operative wheezing often responds to inhaled bronchodilators, deepening the level of anesthesia and/or removal of the source of bronchial irritation. In cases of severe bronchospasm, where the administration of inhaled bronchodilators might be limited by the severity of small airways constriction, IV medications offer an advantage. IV terbutaline seems a reasonable therapy in this setting. This paper should reassure anesthesiologists as to the safety of short term administration of this medication in the operating room. The authors used the doses recommended by the National Heart and Lung Institute expert panel report.

Reviewed by: Thomas J. Mancuso, MD, FAAP
Children's Hospital, Boston, MA