Even though the survival period following the injection of cyanide is short and the subcutaneous (situated or applied under the skin) injection of cyanide in suicide and homicide attempts is rare, a patient who was brought to a hospital in a coma following the subcutaneous self-injection of cyanide, prior to death, had survived for a period of eight hours following the episode, upon being sustained on supportive measures such as haemodialysis (treatment to filter waste and water from the blood).
This was observed in a “Case report – Death by subcutaneous injection of cyanide in Sri Lanka” which was authored by N.L. Abeyasinghe, H.J.M. Perera, and D.S.K. Weerasinghe (all three at the time attached to the Colombo University's Faculty of Medicine's Department of Forensic Medicine and Toxicology) and published in the Journal of Forensic and Legal Medicine (18)4 in May 2011.
In another case, an elderly man was stabbed with a needle and syringe on his abdomen while he was asleep. He progressively developed respiratory failure and coma and died an hour later. Autopsy findings and laboratory analysis confirmed the death as being due to poisoning by cyanide. Hence, Abeyasinghe et al. highlight the need to consider cyanide as a possible agent where there is rapid death with progressive respiratory failure after the injection of an unknown substance. Cyanide poisoning by ingestion is seen in suicidal, accidental and homicidal deaths. The injection of solubilised cyanide appears to be very rare, with fatalities reported following intravenous and subcutaneous parenteral (administered or occurring elsewhere in the body than the mouth and alimentary canal) cyanide exposures.
The cyanide ion is strongly poisonous and has been related to human deaths.
The presence of macular erythematous lesions (made of both flat and raised skin lesions) was observed in this case.
Central respiratory arrest due to histotoxic hypoxia (the inability of the cells to take up or use oxygen from the bloodstream, despite the physiologically normal delivery of oxygen to such cells and tissues) of the respiratory centre is the most attributed mode of death in cyanide toxicity.
It is not uncommon to miss the smell of bitter almond, which is specific for cyanide, because cyanide does not always give off an odour and the ability to smell cyanide is inherited, so there is a wide range of sensitivity in the population and a significant percentage of people who cannot detect the smell. R. Punitha, A. Janani and G. Jayaprakash's “Thorn prick – A tricky case report” notes that the characteristic bitter almond smell of cyanide is not perceived at the time of autopsy as the ability to smell cyanide is not possessed by about 20-40% of the human population since this capacity is inherited as a sex linked recessive trait.
It was recently reported in the inquest of the death of a prominent Sri Lankan businessman that the cause of death was in part, the ingestion of 150 millilitres (ml) of cyanide (potassium cyanide) with food.
R. Vohra discusses a case study on cyanide poisoning at the National Hospital of Sri Lanka (NHSL) in Colombo and the National Poisons Information Centre in the context of the civil war in his “Sri Lanka poison control: Toxicology case studies in narrative”.
“As they (members of the Liberation Tigers of Tamil Eelam [LTTE]) were trying to plant a claymore mine in the North East part of the country, two Tamil Tigers were caught by the military. Each of them immediately tried to swallow a capsule of cyanide. One of them was prevented from swallowing the capsule and he survived. The other became ill and was taken to a peripheral hospital where they specifically treated him for cyanide poisoning with hydroxycobalamin (a vitamin found in food and used as a dietary supplement) without much effect. Twenty-four hours later, he was transferred to the NHSL. The LTTE member who ingested cyanide was admitted to the intensive care unit, then intubated (a medical procedure involving the insertion of a tube into the body) after losing consciousness, although he never had acidosis (when acid builds up or when bicarbonate which is a base is lost) on the blood gas (a measurement of how much oxygen and carbon dioxide are in the blood and determines the acidity of the blood). They didn't check a lactate (an organic acid which is a byproduct constantly produced in the body during normal metabolism and exercise) level, which can be used as a surrogate marker for severe cyanide toxicity. He was given thiosulfate (one dose of 25 ml from the antidote kit) but he remained hypotensive (low blood pressure). He was even given a dose of cobalt edetate/dicobalt edetate at the recommendation of the attending toxicology physician. In the 1970s, studies conducted on sheep suggested that, like hydroxycobalamin, this compound can bind and inactivate cyanide, but that the side effects are poorly tolerated and thus should only be used as a last resort. The thiosulfate was never re-dosed. He arrested respiratorily and died early the next morning.”
In Sri Lanka, as pointed out in Dr. A. Edirisinghe's presentation on “Common poisonous plants in Sri Lanka”, the seeds of the Hondala fruit (Adenia palmata) contains cyanogenic glycoside (bioactive plant products derived from amino acids), Kepunkiriya/Budadakiriya/Dadakiriya/Australian Asthma Weed/Thawa Thawa (Euphorbia hirta) also has features of cyanide poisoning, while the root covering of Tapioca/Cassava/Manioc (Manihot utilissima), too contains the same toxin as Hondala, and are most poisonous (Manioc when improperly cooked). The clinical features range from vomiting, fever, restlessness, dizziness, disorientation, abdominal pain, diarrhoea, necrotising enterocolitis (tissues in the intestine/gut become inflamed and start to die, which can in turn lead to a perforation developing, thereby allowing the contents of the intestine to leak into the abdomen, thus likely causing a dangerous infection) leading to diarrhoea with blood and mucus, abdominal colic (a type of abdominal pain that comes and goes in waves, most often starting and ending suddenly and being of severe intensity), tenderness over the right iliac fossa (the right, inferior part of the abdomen), myocarditis (inflammation of the heart muscle which can weaken the said muscle, thereby making it more difficult for the heart to pump), tender hepatomegaly (enlarged liver), retinopathy (disease of the retina), nausea, drowsiness, dehydration, loose stools, shock, collapse, and convulsions.