hydroxocobalamin and Methemoglobinemia

Historically, the first step in treating cyanide (CN. Chart review: A single-center, retrospective case series of patients who received 5 or 10 g of hydroxocobalamin from 01/01/2011 through 04/30/2019. Data was analyzed using descriptive statistics.. Chart review. We observed a noteworthy temporal association between the formation of methemoglobinemia and the administration of hydroxocobalamin. This does not appear to be an artifact of the CO-oximeters. This could have profound implications for patients who are already hypoxemic or have impaired oxygen carrying capacity from carboxyhemoglobin.

Topics: Adult; Antidotes; Carboxyhemoglobin; Cyanides; Female; Humans; Hydroxocobalamin; Male; Methemoglobin; Methemoglobinemia; Methylene Blue; Middle Aged; Oxygen; Retrospective Studies; Saline Solution; Smoke

Methemoglobinemia is a rare disorder of the blood in which there is an increase in methemoglobin, which occurs when hemoglobin is present in the oxidized form. Methemoglobin impairs hemoglobin's ability to transport oxygen, produces functional anemia, and leads to tissue hypoxia. We report the successful management of a case of refractory hypoxia due to acutely acquired methemoglobinemia in a patient undergoing treatment for coronavirus disease 2019 (COVID-19) pneumonia. The cause of methemoglobinemia in this patient remains unknown. Hypoxia and methemoglobinemia did not respond to methylene blue and required administration of packed red blood cell transfusions.

Topics: Acute Kidney Injury; Aged; Antibodies, Monoclonal, Humanized; Antioxidants; Ascorbic Acid; Betacoronavirus; Coronavirus Infections; Corynebacterium; Corynebacterium Infections; COVID-19; Cytokine Release Syndrome; Enzyme Inhibitors; Erythrocyte Transfusion; Hematinics; Humans; Hydroxocobalamin; Hydroxychloroquine; Hypoxia; Male; Methemoglobinemia; Methylene Blue; Pandemics; Pneumonia, Bacterial; Pneumonia, Viral; Renal Replacement Therapy; Respiratory Insufficiency; SARS-CoV-2; Shock, Septic

Hydroxocobalamin is an effective cyanide antidote. While erythema, hypertension, and chromaturia are recognized side effects, methemoglobinemia has not been reported. Methemoglobin levels are most accurately measured by co-oximetry. We describe an extensively burned patient who developed methemoglobinemia within an hour of hydroxocobalamin administration.. A 47-year old man without genetic deficiencies or abnormal hemoglobin variants presented with 61% body surface area thermal burns and grade 1 inhalation injury sustained during a tugboat engine explosion. On admission, lactate was 9.24 mmol/L, methemoglobin 1%, and carboxyhemoglobin 0.2% by blood gas analysis with co-oximetry. Despite large-volume resuscitation, lactate remained elevated (7-8 mmol/L). Intravenous hydroxocobalamin (5 g) was administered at postburn hour 19 for possible cyanide toxicity. Immediately thereafter, he became hypertensive with reflex bradycardia. Lactate decreased to 5.51 mmol/L, methemoglobin rose to 4.10%, and oxygen saturation by pulse oximetry decreased to 74-80% (despite arterial oxygen saturation of 95% by cooximetry). Methemoglobin concentration peaked at 13.40% at postburn hour 33. Methylene blue was not administered.. Methemoglobinemia in our patient was temporally associated with hydroxocobalamin administration.

Topics: Antidotes; Burns; Burns, Inhalation; Cyanides; Humans; Hydroxocobalamin; Male; Methemoglobinemia; Middle Aged

Topics: Antidotes; Burns; Humans; Hydroxocobalamin; Methemoglobinemia; Smoke Inhalation Injury

Most fire-related deaths are attributable to smoke inhalation rather than burns. The inhalation of fire smoke, which contains not only carbon monoxide but also a complex mixture of gases, seems to be the major cause of morbidity and mortality in fire victims, mainly in enclosed spaces. Cyanide gas exposure is quite common during smoke inhalation, and cyanide is present in the blood of fire victims in most cases and may play an important role in death by smoke inhalation. Cyanide poisoning may, however, be difficult to diagnose and treat. In these children, hydrogen cyanide seems to be a major source of concern, and the rapid administration of the antidote, hydroxocobalamin, may be critical for these children.European experts recently met to formulate an algorithm for prehospital and hospital management of adult patients with acute cyanide poisoning. Subsequently, a group of European pediatric experts met to evaluate and adopt that algorithm for use in the pediatric population.

Topics: 4-Aminopyridine; Age Factors; Algorithms; Antidotes; Child; Child, Preschool; Cyanides; Disease Management; Disease Susceptibility; Emergencies; Emergency Medical Services; Europe; Fires; Humans; Hydroxocobalamin; Infant; Methemoglobinemia; Poisoning; Smoke; Smoke Inhalation Injury; Sodium Nitrite; Thiosulfates