Cardiac Arrhythmias during Theophylline Toxicity: Methods (2)
Serial STC determinations were obtained, generally at four-hour intervals until STC was less than 20 mg/L, then less frequently. If the second STC (obtained at the time of entry into the study) was greater than the initial STC (reflecting continued absorption from sustained release preparations), subsequent STCs were measured more frequently. All medical problems, including theophylline toxicity and related complications, were managed by the patients physician(s). The continuous ECG recording was continued until (1) more than 24 hours had elapsed and the STC was less than 20 mg/L for more than 12 hours, or (2) the patient was treated entirely in the emergency department (ED) and discharged after clinical toxicity had resolved and the STC was declining steadily. Clinical manifestations of toxicity, treatment of toxicity or related complications, and outcome were noted. buy asthma inhalers
Continuous Electrocardiographic Recording Analysis
A recording system (Delmar Avionics 9000A, Irvine, CA) was used for all recordings at MCV and another system (Marquette Electronics, Inc, Milwaukee, WI) was used at MVAMC. The following data were recorded hourly: (1) minimum, average, and maximum heart rate; (2) presence and frequency of VPB, ventricular couplets, and ventricular runs (including rate, duration, and number of ventricular runs); and (3) presence of supraventricular ectopic beat (SVE), and number and duration of SVE runs. All tapes were interpreted using direct operator interaction and overreading.