CASE REPORT
A 38 year-old female with a past medical history of huffing-associated
cardiac arrest, was standing at the bus stop when she was witnessed to
experience tonic-clonic seizure activity followed by collapse. Emergency
Medical Services arrived on the scene shortly thereafter and she was
found to be in ventricular fibrillation. Epinephrine 3mg and Amiodarone
450mg were administered as bolus therapy and she was defibrillated thee
time for persistent ventricular tachycardia. The patient had return of
spontaneous circulation, but in the emergency department (ED) developed
torsade de pointes (Figure, Panel A ), which degenerated into
ventricular fibrillation requiring defibrillation. According to
acquaintance reports, the patient was huffing volatile chemicals just
prior to her arrest.
In the ED, her physical examination was unrevealing. Her laboratory
analysis was notable for a critically low serum potassium concentration
of 2.6 mEq/L (normal range 3.5-4.5), high sensitivity troponin-I of
2,406 ng/L (reference range < 34 ng/L), and elevated serum
lactate at 6.3 mmol/L (reference range 0.3-2.0 mmol/L); consistent with
acidosis from resuscitated sudden cardiac death and resultant systemic
hypoperfusion. The patient was intubated and transferred to the
intensive care unit and during transit, torsade de pointes recurred
(Figure, Panel B ), resolving spontaneously. She was admitted
with a primary diagnosis of cardiac arrest secondary to
tetrafluoroethane inhalation. Electrocardiography (ECG) revealed a
rate-corrected QT interval (QTc) of 502 ms. Emergent transthoracic
echocardiography revealed normal left ventricular systolic function with
an ejection fraction of 60% by Simpson’s biplane method without
segmental wall motion abnormalities. Therefore, coronary angiography was
deferred despite elevated biomarkers. Urine toxicology was positive for
amphetamines (1,000 ng/ml cutoff for detection), but negative for
cocaine. Serum toxicology was negative for ethanol (<10
ng/ml). Toxicology for volatile petrochemicals was not available in our
laboratory. Unfortunately, the patient had severe anoxic brain injury
with marked autonomic dysfunction and supportive care was ultimately
withdrawn.