Unrecognized bulimia nervosa: a potential cause of perioperative cardiac dysrhythmias

To report serious cardiac dysrhythmias in two patients whose bulimia nervosa was not revealed during preoperative screening.

Case #1: A 25-yr-old woman with preoperative hypokalemia (K+ = 3.1 mEq x l(-1)) required anesthesia for removal of a wrist ganglion. She claimed the hypokalemia was of unknown etiology, and denied other medical problems. Shortly after induction of anesthesia with thiopental and isoflurane, the ECG revealed two runs of torsades de pointes. This was successfully treated by decreasing pulmonary ventilation, allowing P(ET)CO2 to increase from 32 to 45 mm Hg. Case #2: A 39-yr-old woman who denied any medical problems received propofol, rocuronium sevoflurane and N2O during general anesthesia for breast augmentation. In the PACU, the patient complained of light-headedness, and the ECG revealed a heart rate of 44 bpm with P-R interval of 0.42 sec. Following 0.5 mg atropine, the heart rate increased but the P-R interval remained prolonged (0.36 sec) and the corrected Q-T interval was 0.51 sec. Treatment with 2.5 g MgSO4, 20 mEq KCl, and 9.4 mEq calcium gluconate i.v. normalized the Q-T interval, and decreased the P-R interval to 0.22 sec. Upon specific questioning, she admitted to a remote history of bulimia, but denied any bulimic behavior for the last 16 yr.

Two patients with histories of eating disorders failed to disclose this information during preoperative evaluation. Perioperative cardiac dysrhythmias developed in these patients, even though they claimed that eating behavior had returned to normal.