Massive Nonfatal Hydroxychloroquine Ingestion in a Pediatric Patient.

BACKGROUND: Hydroxychloroquine overdose is rare but potentially lethal. Hydroxychloroquine overdose symptoms are characterized by central nervous system toxicity, cardiac toxicity, and hypokalemia. Recommended treatment consists of epinephrine, high-dose diazepam, and careful potassium repletion. Few pediatric hydroxychloroquine overdoses have been reported. CASE REPORT: We describe a 14-year-old girl who ingested 10 g (172 mg/kg) of hydroxychloroquine. She developed tachycardia, hypotension, and hypokalemia. She was intubated and treated with diazepam and epinephrine infusions and potassium supplementation. Her serum hydroxychloroquine concentration obtained 10 h after ingestion was 13,000 ng/mL (reference range 500-2000 ng/mL). The patient made a full medical recovery. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Pediatric hydroxychloroquine overdoses are reported rarely, and the toxic and lethal doses of hydroxychloroquine ingestion have not been established. This case of a teenaged patient who ingested 10 g of hydroxychloroquine and survived provides additional information that may be used to help establish toxic and lethal doses of ingestion.

Delayed-Onset Portal Venous Thrombosis After Ingestion of 3% Hydrogen Peroxide.

BACKGROUND: Identification of portal venous gas on radiographic imaging is well documented after the ingestion of hydrogen peroxide, as is its resolution after hyperbaric therapy. Although hyperbaric therapy may resolve the gastrointestinal symptoms associated with the presence of portal venous gas, the principle rationale for performing hyperbaric therapy is to prevent subsequent central nervous system oxygen embolization. CASE REPORT: We describe a patient with portal venous gas identified by computed tomography after the ingestion of 3% hydrogen peroxide, managed without hyperbaric therapy, who subsequently developed portal venous thrombosis. We are not aware of this complication being previously described from hydrogen peroxide ingestion. The case is complicated by the coexistence of a self-inflicted stab wound, leading to exploratory laparotomy in a patient predisposed to arterial vascular occlusion. Why Should an EmergencyPhysicianBeAware of This? Emergency physicians will encounter patients after the ingestion of hydrogen peroxide who, despite not having symptoms of central nervous system emboli, have portal venous gas identified on radiographic imaging. Being aware that the principle rationale for prophylactic utilization of hyperbaric therapy is to prevent subsequent central nervous system emboli, and that in at least one case, delayed-onset portal venous thrombosis has occurred without hyperbaric therapy may help contribute to clinical decision-making.

Single Versus Multiple Hyperbaric Sessions for Carbon Monoxide Poisoning in a Murine Model.

Hyperbaric oxygen (HBO) has been advocated for treatment of acute carbon monoxide (CO) poisoning. There exists considerable debate as to whether HBO prevents delayed neurologic sequelae (DNS) due to CO poisoning. Additionally, existing data in the literature supporting HBO efficacy do not identify an optimal number of HBO treatments. We sought to determine in a mouse model whether there is a difference between one versus multiple HBO sessions for the prevention of DNS. Fifty mice were randomized into five groups of ten mice each: (1) control, receiving no CO exposure or treatment; (2) CO poisoned, receiving no treatment (CO group); (3) CO poisoned, receiving normobaric oxygen for 58 min following the end of exposure (CO + NBO group); (4) CO poisoned, followed by one session of HBO(CO + HBO1); and (5) CO poisoned, followed by three HBO treatment sessions, one every 6 h (CO + HBO3). Prior to poisoning, all animals were trained in step-down latency (SDL) and step-up latency (SUL) tasks. One week after exposure and treatment, all five groups were retested to evaluate the retention of this training. There was no difference detected among groups in SDL (p = 0.67 among all groups) when evaluated using a Kruskal-Wallis test. There was a significant difference among groups in SUL (p = 0.027 among all groups) when evaluated using a Kruskal-Wallis test. When individual groups were compared using a Wilcoxon signed-rank test with Bonferroni correction, there were no statistically significant differences in either SDL or SUL. There was no difference between groups treated with either one or three HBO sessions. One possibility to explain this might be that HBO sessions administered some time after a CO exposure may enhance the lipid peroxidation cascade and worsen neurologic outcomes; alternatively, HBO may simply impart no benefit when compared to NBO.