Sodium Nitrate Overdose: Nitrates are prevalent in the environment as well as being used as meat Preservatives and in medications. Nitrite-containing items have been used as recreational drugs because of their mild hypoxia-induced euphoria. Tiny levels in one’s diet are considered safe. Although nitrate salts are rarely used to cause death, they have been used as suicide and homicide aids.
The oxidation of hemoglobin ferrous (Fe+2) iron (Hb) to ferric (Fe+3) form (methemoglobin, MetHb) results in death due to a loss in the blood’s oxygen-carrying capacity. According to this study, sodium nitrite was ingested by two college students (one of whom had somewhat deteriorated) and a middle-aged adult. Methemoglobinemia was each of the victims’ terminal illnesses in these circumstances. A chemical form of sodium nitrite was identified around the bodies in chemical form. MetHb was found in each decedent’s postmortem blood. MetHb levels in each of the two deceased with a brief postmortem time were lower than those previously reported in scientific literature.
The mildly degraded person’s MetHb readings were higher than the other two, although still lower than the previously deemed deadly concentration. As the findings of these examples show, mortality caused by sodium nitrite should not rely entirely on a person’s MetHb values. The discussion of the instances is followed by an outline of MetHb’s pathophysiology and a review of the current literature. Unintentional exposure to hazardous salts including nitrite or nitrate is a known cause of acquired methemoglobinemia (MetHb). This blood anomaly can be dangerous if not detected and treated soon.
This is a set of Situations in which
Five occurrences of severe methemoglobinemia induced by large sodium nitrite ingestion were reported to the California Poison Control System in 2019, three of which resulted in death. One patient lived despite swallowing 60 kilograms of the medicine, which ranged from 15 grams to more than 112 kilograms. A patient’s methemoglobin level was revealed to be 73 percent. Methylene blue was given early in the course of the sickness to the two patients who survived. One patient required higher methylene blue dosages than in prior occurrences of nitrite-associated methemoglobinemia. In the patients that survived, all symptoms vanished within 24 hours.
MetHb, which is caused by NaNO2 or NaNO3, is a rare technique of suicide that was only recently found; the first instance in the literature happened in New Zealand in 2010. This case series includes 28 cases of sudden death in Ontario, Canada, between 1980 and 2020, with evidence of MetHb and/or hazardous salt ingestion. In 25 of the 28 instances studied, sodium nitrite and sodium nitrate salts were confirmed to be the cause of death. As our statistics revealed, this method of suicide was being used increasingly frequently in our province’s population year after year, with the majority of cases occurring in the latter two years of our study.
Scene evidence that points to ingestion of a fatal salt, as well as the body’s typical grey-purple lividity, can all be used to discover MetHb after a death. High methemoglobin saturation can be seen in postmortem blood tests, which is diagnostic. Both inside intracardiac blood on chest MRIs and postmortem blood samples preserved in tubes, postmortem MRI verifies the T1-bright (hyperintense) signal of the blood. Sodium nitrite can produce methemoglobinemia and hypotension when ingested, however intentional intake is extremely unusual.
What is the significance of knowing this for an ER physician?
The extreme toxicity associated with purposely ingesting high amounts of sodium nitrite may be seen in action here. Higher initial or more frequent dosages of methylene blue should be explored in therapy compared to standard practice. Because sodium nitrite is freely available online and frequently discussed on numerous suicide forums, it may become increasingly popular in the emergency department.
Hypotension
At doses less than twice the normal therapeutic dosage, it has been connected to severe hypotension, methemoglobinemia, and mortality. Nitrite of sodium An episode of hypotension might happen in conjunction with another event or it can happen on its own. Sodium nitrite should be used to treat cyanide poisoning. If the patient’s oxygen or cardiovascular reserve (e.g., smoke inhalation victims, anemia, substantial blood loss) or methemoglobinemia risk (e.g., cardiac or respiratory compromise, pre-existing anemia) has been reduced, or if the patient is at higher risk of developing methemoglobinemia, sodium nitrite should be considered (e.g., congenital methemoglobin reductase deficiency).
Methemoglobinemia
Many cases of cyanide overdose can be managed without antidotes, especially in individuals who are aware of the situation and show no signs of acute toxicity. Treatment with sodium nitrite involves constant monitoring of patients to ensure adequate blood and oxygen flow. During sodium nitrite treatment, oxygen should be given to monitor methemoglobin levels. When sodium nitrite is administered to people, their methemoglobin amounts vary greatly. In adults, two 300-mg sodium nitrite doses were observed to boost hemoglobin levels by up to 58 percent.
When using sodium nitrite, drugs that can cause methemoglobinemia, such as procaine and nitroprusside, should be used with caution. When delivering sodium nitrite to patients who may be at risk of hemodynamic effects from increased venous dilation, caution should be exercised. The rate of sodium nitrite infusion should be reduced during and after treatment to avoid hypotension.
Anemia
Sodium nitrite should be used with caution in patients who have a history of anemia. Anemic patients produce more methemoglobin than people with normal red blood cell (RBC) quantities (as a percentage of total hemoglobin). As a best practice advice, they should get a sodium nitrite dose that is proportional to their oxygen-carrying capacity.
Smoke Inhalation Causes Asthma and Allergies
Methemoglobin generation from sodium nitrite should be utilized with caution in patients with smoke inhalation injury or carbon monoxide poisoning since it has the potential to worsen hypoxia.
Newborns and infants
When neonates and newborns are given sodium nitrite, they are more likely to develop severe methemoglobinemia than adults and older pediatric patients. Lower doses of medication should be given to children.
G6PD gene Deficiency caused by Gestational age
In G6PD deficient patients, sodium nitrite can cause a hemolytic crisis, hence alternate therapeutic options should be explored. A sudden drop in hematocrit in patients with G6PD deficiency should be monitored. Sodium nitrite users with G6PD deficiency may require an exchange transfusion. Sodium nitrite should be used with caution when using hypertension medicines, diuretics, or diuretics that cause volume depletion. PDE5 inhibitors should be avoided because they are known to enhance vascular nitric oxide.
Overdosage
Excess sodium nitrite doses can cause hypotension and dangerous levels of methemoglobin. Sodium nitrite in oral doses of 1 g and intravenous doses of 600 mg has been found to cause or contribute to mortality in adults. After taking an adult amount of sodium nitrite, a 17-month-old child died (300 mg IV, followed by a second dose of 150 mg). The use of intravenous methylene blue to treat severe methemoglobinemia has been recorded in the medical literature; nevertheless, cyanide bound to methemoglobin may also be released.
At a methemoglobin concentration of 10% to 20%, cyanosis can begin to manifest. Other clinical indications and symptoms of sodium nitrite poisoning, such as anxiety, dyspnea, nausea, and tachycardia, may occur at levels as low as 15% methemoglobin. More acute indications and symptoms, such as cardiac dysrhythmias, circulatory failure, and central nervous system depression, become apparent as methemoglobin levels rise, and levels surpassing 70% are frequently fatal.
