Abstract 470

Background: Electrocardiograms (EKG's) are frequently obtained in children with acute asthma to evaluate cardiac murmurs or dysrhythmias. Despite available data regarding arrhythmias in these children, there is little knowledge regarding other types of EKG abnormalities. Methods: We reviewed all EKG's performed on asthmatic children admitted to the pediatric intensive care unit over a 5-year period. Patients with heart disease or any chronic medical condition other than asthma were excluded. EKG's were evaluated for rate, rhythm, PR interval, QRS duration, corrected QT interval (QT c), T wave morphologies, and left ventricular voltage. Patient variables included use of medications, respiratory rate, intubation/sedation, acidosis, serum electrolytes, oxygen saturation, and years of asthma. Relationships between EKG findings and patient variables were examined. Results: Thirty-nine patients were studied (31% male, 69% female). The average age was 7 ± 4 years (SD). Medications administered included albuterol (n=39), aminophylline (n=27), cromolyn sodium (n=5), and isoproterenol (n=2). The average heart rate was 132 ± 26 beats per minute. There were no arrhythmias seen. All PR intervals and QRS durations were normal. The QT c was prolonged in 6 (15%) patients. T wave flattening was seen in the inferior (n=11, (28%)) and lateral (n=9, (23%)) leads. Three patients (7.7%) met voltage criteria for left ventricular hypertrophy. Using multivariate techniques, there were significant relationships seen between: 1) time since previous dose of albuterol and T wave flattening in either inferior or lateral leads, 2) aminophylline use and left ventricular voltage, 3) intubation/sedation and QT c, and 4) frequency of albuterol administration and heart rate. Conclusions: Several types of EKG abnormalities may be seen in severely ill asthmatic children. These abnormalities were associated with albuterol and aminophylline.