William McGee, MD, FCCM
Professor
Baystate Medical Center, United States
Disclosure information not submitted.
Asad Khan
Fellow
UMASS Medical School-Baystate Medical Center
Broad Brook, Connecticut, United States
Disclosure information not submitted.
Title: "Common Things Are Common”: Red Herrings in the Diagnosis of Acetaminophen and Salicylate Overdose
Case Report Body:
Introduction: Overdose from over-the-counter (OTC) analgesics has increased significantly over the past 20 years, with acetaminophen and aspirin accounting for up to 97% of all deaths secondary to OTC overdose. The initial manifestations of acetaminophen and salicylate (aspirin) poisoning are often nonspecific and are frequently missed, especially in the presence of concomitant toxidromes.
Description: We report the case of a 47-year-old female who presented after intentional toxic ingestion of 200 pills of multiple medications. These included acetaminophen, aspirin, quetiapine and zolpidem. While initially hemodynamically stable, she appeared tremulous and diaphoretic, with rigidity and clonus on examination. With a toxicology screen in process, the patient was treated with intravenous lorazepam for suspected serotonin syndrome and a bicarbonate drip for possible salicylate toxicity. Her initial salicylate level was 31.2mg/dL and four-hour acetaminophen level was 211mg/L. Shortly after, the patient developed worsening tachypnea and altered mental status with a serum pH of 7.13 and anion gap of 35. Serum lactate was elevated at 14.8. The patient was transferred to the intensive care unit (ICU) and was immediately treated with acetylcysteine and activated charcoal. She required intubation for airway protection and optimization of her minute ventilation and received emergent hemodialysis. The patient was successfully treated with interval improvement in her mentation and was transferred out of the ICU within 72 hours of her presentation.
Discussion: Our case demonstrates the importance of maintaining a high index of suspicion for acetaminophen and salicylate poisoning. Her initial treatment was delayed due to a concern for serotonin syndrome. Clinical hindsight reveals that these were signs of acetaminophen and salicylate toxicity. Salicylate intoxication often has a delayed presentation and therefore it is crucial to look for subtle clinical findings in any patient with a suspected overdose and an elevated anion gap. While toxic ingestion of these medications can have devastating, possibly fatal adverse effects, a high index of suspicion and knowledge of common OTC medications can lead to early diagnosis with appropriate management having a high chance of clinical success.