Utility of Hypertonic Saline and Diazepam in COVID-19-Related Hydroxychloroquine Toxicity

Abstract

Background: Hydroxychloroquine (HCQ) poisoning is a life-threatening but treatable toxic ingestion. The scale of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (COVID-19) and the controversial suggestion that HCQ is a treatment option have led to a significant increase in HCQ use. HCQ poisoning should be at the top-of-mind for emergency providers in cases of toxic ingestion. Treatment for HCQ poisoning includes sodium bicarbonate, epinephrine, and aggressive electrolyte repletion. We highlight the use of hypertonic saline and diazepam.

Case report: We describe the case of a 37-year-old man who presented to the emergency department after the ingestion of approximately 16 g of HCQ tablets (initial serum concentration 4270 ng/mL). He was treated with an epinephrine infusion, hypertonic sodium chloride, high-dose diazepam, sodium bicarbonate, and aggressive potassium repletion. Persistent altered mental status necessitated intubation, and he was managed in the medical intensive care unit until his QRS widening and QTc prolongation resolved. After his mental status improved and it was confirmed that his ingestion was not with the intent to self-harm, he was discharged home with outpatient follow-up. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: For patients presenting with HCQ overdose and an unknown initial serum potassium level, high-dose diazepam and hypertonic sodium chloride should be started immediately for the patient with widened QRS. The choice of hypertonic sodium chloride instead of sodium bicarbonate is to avoid exacerbating underlying hypokalemia which may in turn potentiate unstable dysrhythmia. In addition, early intubation should be a priority in vomiting patients because both HCQ toxicity and high-dose diazepam cause profound sedation.

Keywords: COVID-19; ECG; SARS-CoV-2; arrhythmia; chloroquine; diazepam; dysrhythmia; epinephrine; hydroxychloroquine; hypertonic saline; hypertonic sodium chloride; overdose; plaquenil; sodium bicarbonate; toxicology.

Figure 1

Initial electrocardiogram in the emergency department showing bradycardia with complete AV block, wide QRS of 124 ms, and prolonged QTc of 548 ms.

Figure 2

Electrocardiogram obtained early in the intensive care unit course. The patient had recurrence of QTc prolongation of 666 ms with TU-fusion waves.

Figure 3

Electrocardiogram obtained later in the intensive care unit course. The patient's QTc interval narrowed to 440 ms with prominent U waves.

Figure 4

Electrocardiogram obtained before discharge. The patient had a narrow QRS of 92 ms and a normal QTc of 424 ms.