Medical Student Lincoln Memorial University-DeBusk College of Osteopathic Medicine Knoxville, Tennessee, United States
Clinical Scenario or Case: This case presentation describes an 18-year-old male who presented to the emergency department in severe respiratory distress following intentional ingestion of sodium nitrite in a suicide attempt. On ED arrival, he had a GCS score of 3, demonstrated decerebrate posturing and was hemodynamically unstable. Initial arterial blood gas revealed a methemoglobin level of 31.0%, pH of 7.20, and pO2 of 283.0. Despite receiving four doses of methylene blue, the patient experienced multiple cardiac arrests and was ultimately pronounced brain dead on hospital day 10 in the ICU.
Evidence/Literature Review: Sodium nitrite is a white, odorless powder commonly used as a meat preservative. When ingested, it causes oxidation of heme iron from the ferrous (Fe2+) to the ferric (Fe3+) state, forming methemoglobin, which is unable to bind oxygen and causes tissue hypoxia. Methemoglobinemia is characterized by weakness, cyanosis, loss of consciousness, and potentially death.
Unique Aspects of Case: This case is notable due to the rapid progression of sodium nitrite induced methemoglobinemia in a previously healthy individual ultimately leading to brain death despite aggressive treatment. Sodium nitrite ingestion as a suicide method is increasingly reported with a 253% increase in the use of nitrates and nitrites as a mechanism of suicide from 2018 to 2021. Additionally, sodium nitrite is commonly included in suicide kits promoted on online suicide forums and remains easily accessible through major retailers such as Amazon and Walmart- without age restrictions or verification.
Recommendations/Conclusions: This case highlights the importance of early recognition and prompt methylene blue administration in patients with suspected sodium nitrite overdose. It also emphasizes the need for increased availability of antidote methylene blue in emergency departments and prehospital EMS given the narrow therapeutic window of sodium nitrite induced methemoglobinemia. However, this necessity presents its own challenge, as methylene blue requires mixing prior to administration and has a limited shelf life once prepared.
