Death scene evaluation in a case of fatal accidental carbon monoxide toxicity

Exposure of humans to high concentrations of carbon monoxide can result in death, due to the formation of carboxyhaemoglobin (COHb), which impairs the oxygen carrying capacity of the haemoglobin. Carbon monoxide is responsible of a great number of accidental domestic poisonings and deaths throughout the world, particularly in homes that have faulty or poorly vented combustion appliances. A case is reported, in which a 21-year-old woman was found dead, due to carbon monoxide poisoning from a gas water heater, despite the puzzling evidence that the heater has been used for more than 10 years without any problem. An evaluation of the exposure to CO was performed, by measuiring the rate of production of CO from the heater, and using the Coburn-Forster-Kane equation to describe the kinetics of the poisoning process. The death was attributed to an accidental poisoning from carbon monoxide due to a sum of unfortunate circumstances.     

Unusual carbon monoxide poisoning

Despite of indicative death scenes or characteristic findings of the external examination, about 40% of the accidental fatal intoxications due to carbon monoxide are not recognized before the performance of the autopsy. Six cases are reported which illustrate possible reasons for the delayed establishment of the diagnosis: unusual circumstances of the intoxication or sources of carbon monoxide, only subtle degree or lack of external signs of the intoxication or a competing cause of death at autopsy.--Cases 1 and 2: 53, respectively 54-year-old couple, found dead in a caravan, extreme putrefaction of the bodies, spectrophotometric detection of the fatal carboxyhaemoglobin level in oedema fluid of the scalp.--Case 3: 23-year-old lorry driver, found dead in the tightly closed cab of his lorry, operation of a source of electricity with "environmentally friendly" fuel, carboxyhaemoglobin level 83%.--Case 4: 19-year-old man, found dead in the flat of friends, removal of the CO-source before alerting the police forces, lack of the bright pink coloration of livor mortis, haemopericardium due to atrial rupture at postmortem examination, carboxyhaemoglobin level 65%.--Case 5: 27-year-old man, found dead in his flat, advanced decomposition of the body, residues of a charcoal fire in a metal bucket in the sink, carboxyhaemoglobin level 80%.--Case 6: 42-year-old woman, lying dead in the garage beside her car, engine switched-off, ignition key next to the body on the floor under the car, carboxyhaemoglobin level 46%.     

Interaction between carbon monoxide and ethanol in fire fatalities.

Impairment due to ethanol is clearly a risk factor in deaths due to fire. However, it is less clear whether there is a physiological interaction between ethanol and carbon monoxide (CO) that would alter the carboxyhemoglobin saturation level (COHb sat.) that accounts for death. In an attempt to explore this issue further, 196 fire fatalities investigated by the Office of the Chief Medical Examiner, State of Maryland over a 3-year period were examined. COHb sat. and blood ethanol concentrations (BAC) were tabulated. Twelve cases positive for therapeutic or abused drugs other than lidocaine or atropine were excluded; 184 cases were included. The data indicate that ethanol does not affect the COHb sat. that accounts for death, since the percentage of cases positive for ethanol at a given COHb range shows no trends. Therefore, we conclude that although ethanol remains a risk factor in fire fatalities, the risk appears to be related to the impairment that it produces as opposed to a direct interaction with CO.     

Measuring carbon monoxide content in muscles

A method ist described to determine the CO-content in the tissue of muscles. The prepared tissue is pulverized in a swinging mill at the temperature of liquid nitrogen. Parts of the powder are weighed into headspace vessels. Carbon monoxide ist ejected by a formerly described method and measured gaschromatographically. The Fe-content is determined after an acid disintegration by AAS. Acute intoxications lead to higher CO-contents in heart than in periphere muscles. Chronic exposure to carbon monoxide does not produce these differences.     

Production of carbon monoxide in cadavers

Carbon monoxide (CO), total hemoglobin (Hb) and carboxyhemoglobin (HbCO) in the blood and reddish discolored body cavity fluids of cadavers which had not been exposed to fire and CO were analyzed. In 13 cadavers found on land, the maximum saturation of HbCO in the blood was 3.6%, and was 10.1% in the body cavity fluids. There was only one case in which the HbCO saturations in the body cavity fluids were more than 10%. In seven drowned bodies found in fresh water, the highest HbCO saturation in the blood was 6.1%, and was 44.1% in the body cavity fluids. There were three cases in which the HbCO saturations in the body cavity fluids were more than 10%. In 12 drowned bodies found in sea water, the HbCO saturations in the blood were not more than 6.2%, and the maximum saturation of HbCO in the body cavity fluids was 83.7%. There were eight cases in which the HbCO saturations in the body cavity fluids were more than 10%. The results seem to indicate that the interpretation of HbCO saturation in the blood would not be affected significantly by the postmortem formation of CO, and that body cavity fluids should not be used for CO determination.     

一氧化碳（CO）中毒检测方法

作者查阅近20年国内外相关文献的基础上,对一氧化碳(CO)中毒的检验方法进行了全面的阐述,同时对每种方法的优缺点和适用条件作了比较,并对适用于我国国情的顶空气质联用法进行了改良.     

Four deaths due to carbon monoxide poisoning in car washes.

In a period of 13 months, three separate incidents of lethal carbon monoxide (CO) poisoning in closed car wash bays resulted in the deaths of 4 white men aged 20 to 36 years. Each man appears to have been intoxicated with mind-altering substances, which may impair judgment, perception of outside conditions, and self-awareness. All four died in winter months. For three men, the deaths were ruled accidental, and for the remaining man, the previous deaths appear to have provided a model for suicide. Warning signs may not be effective to prevent future CO deaths in car washes because of the possible role of intoxication. Mechanical or electronic methods to prevent a bay door from closing completely may be preferable.     

Postmortem formation of carbon monoxide

Since carbon monoxide (CO) production after death was suggested in a drowned body, CO and carboxyhemoglobin (HbCO) levels in blood and body cavity fluids of cadavers which were not exposed to fire and CO have been analyzed. CO released from the tissues was determined by gas chromatography and gas chromatography-mass spectrometry, and the total concentration of hemoglobin (Hb) was measured as cyanmethemoglobin (CNmHb). The HbCO level was calculated by the ratio of CO content and CO-binding capacity. CO levels (ml/100 g at STP) of the seven cases in which blood and body cavity fluids could be collected ranged from 0.13 to 0.87 in blood and 0.02 to 0.80 in body cavity fluids. HbCO levels in blood and body cavity fluids were from 0.3 to 6.0% and from 2.3 to 44.1%, respectively. In a typical case showing postmortem formation of CO, the CO levels in body cavity fluids were higher than that in blood. It is suggested that CO in a putrefied body is due to CO in blood prior to death and the CO formed by the decomposition of Hb, myoglobin and other substances during putrefaction. The significance of HbCO levels in body cavity fluids of cases with marked postmortem decomposition seems difficult to interpret without the value of HbCO in blood.     

Lethal poisoning with carbon monoxide in children

Expert evaluations of 39 cases with lethal poisoning of children with carbon monoxide are analyzed. Epidemiological data are presented. Mechanism of toxic effect of carbon monoxide is discussed. Pathomorphological data and forensic chemical findings are analyzed.     

Narcolepsy mimicking suicidal carbon monoxide poisoning

We present a case of narcolepsy mimicking suicidal carbon monoxide poisoning. The signs and symptoms of narcolepsy in this previously undiagnosed man were initially missed, which emphasizes the importance of extracting a detailed history of a decedent's behavior prior to his or her death. Narcoleptics are often involved in motor vehicle accidents. This report again demonstrates that narcolepsy and driving don't mix, even when the vehicle is stationary. We also briefly review the various sleep disorders.     

Non-intentional motor vehicle-related carbon monoxide deaths-revisited

A study of non-intentional, motor vehicle-related, carbon monoxide-related deaths was performed on the case files of the Office of the Medical Examiner of Metropolitan Dade Country in Miami, FL (USA) during the years 1980-1984. A total of 15 cases were collected during that time period. These are presented in some detail. A discussion ensues that compares the similar circumstances of these cases, notably running the engine of an automobile in an enclosed space, with older reports in the literature which emphasized defective vehicle exhaust systems as the leading etiology for these deaths.     

Hyperuricemia in rats during acute carbon monoxide poisoning

The effect of carbon monoxide (CO) inhalation on plasma levels of uric acid and hypoxanthine in rats was investigated. Exposure to 3% CO caused respiratory arrest within about 2 minutes. The plasma uric acid level of CO-treated rats increased to 157% above that of ether-treated rats. When rats were exposed to 1% or 0.8% CO, the exposure periods until the onset of respiratory arrest were prolonged, and plasma uric acid levels at respiratory arrest were further elevated. Plasma uric acid levels at respiratory arrest increased with prolongation of the exposure periods. Under our experimental conditions, hypoxanthine or xanthine was not detected in plasma of CO-treated rats. These results are discussed in relation to the hyperuricemia in hemorrhagic shock or hypoxemia: CO-induced hyperuricemia can be attributed to the stimulated degradation of adenine nucleotides under tissue anoxia, and thus could be an excellent parameter of tissue anoxia.     

Suicidal carbon monoxide inhalation of exhaust fumes. Investigation of cases

The inhalation of automobile exhaust gases is a relatively frequent suicidal method. Two such cases of special interest to forensic pathology and toxicology have been introduced. In case 1, a suicide note disclosed the victim's mental state, the inside conditions of the car, and toxic effects of automobile exhaust. In case 2, a reconstruction experiment has revealed important factors for the investigation of the scene, such as the size of a vinyl hose, the conditions of connecting site of the hose with the exhaust pipe, etc.     

血液保存中碳氧血红蛋白稳定性研究进展

通过分析近年来有关血液样品中碳氧血红蛋白稳定性方面的研究资料,发现血液中碳氧血红蛋白的稳定性受到盛放容器、保存温度、容器顶部空气体积、初始HbCO饱和度及防腐剂的添加与否的影响,其中保存温度、容器顶部空气体积及初始HbCO饱和度则是其主要影响因素。     

Liver damage in rats during acute carbon monoxide poisoning

Plasma leucine aminopeptidase (LAP) levels and respiration rates of isolated liver mitochondria were studied in carbon monoxide (CO)-poisoned rats sampled at respiratory arrest. An increase in LAP levels paralleled a decrease in the respiratory control ratio and the $\text{ADP}\text{O}$ ratio. The results suggest that the damage to mitochondria closely correlates with the liver damage in rats during acute CO poisoning.     

36例一氧化碳中毒分析

本文对36例59人因管道煤气引起一氧化碳中毒案例进行了分析. 资料分析 资料来源:本文收集1993年10月至1997年12月经东风汽车公司公安处检验鉴定的东风汽车公司范围内管道煤气用户中毒案共36例59人,其中死亡58人,仅1人经抢救存活.     

An unusual case of suicidal carbon monoxide poisoning

A 35 years old student with prior suicidal tendencies was found dead laying enclosed in a plastic-bag together with four plastic-bags of minor capacity. Three bags were opened by cuts and empty, one bag contained 73 1 of 83.2 Vol.% carbon monoxide. Postmortem carboxyhemoglobin concentrations in blood of five different regions of the corpse ranged from 80.3% to 93.4%. From the circumstances--chemicals and apparatus--it could be reconstructed that carbon monoxide was produced by the reactions of formic acid and sulfuric acid.     

36例一氧化碳中毒分析

本文对36例59人因管道煤气引起一氧化碳中毒案例进行了分析。资料分析资料来源:本文收集1993年10月至1997年12月经东风汽车公司公安处检验鉴定的东风汽车公司范围内管道煤气用户中毒案共36例59人,其中死亡58人,仅1人经抢救存活。资料统计:季节分布:春季12例26人;夏季8例12人;秋季6例7人;冬季10例14人。一次中毒涉及人数:1人:19例;2人:11例;3人:3例;4人:1例;5人:1例。其中有3例中毒中有2人有逃生行为,1人经抢救存活。发现情况:36例均由邻居、家人、同事嗅到煤气味或尸臭味或因没去上班而发现。死后24ｈ内发现27例40人,24～48ｈ6例11人,48ｈ以…     

Experimental study on postmortem formation of carbon monoxide

Rats were drowned and kept immersed for 1 month in either boiled city water, or boiled or unboiled fresh water collected from a river. A small amount of carbon monoxide (CO) formed after death and a low carboxyhemoglobin (HbCO) saturation was found in blood and thoracic cavity fluid of the animals immersed in boiled city water and in boiled fresh water. A considerable amount of CO and a high HbCO saturation was observed in blood and thoracic cavity fluid in two out of three rats immersed in unboiled fresh water at 4-6 degrees C, and in one out of three at 6-16 degrees C. It is suggested that microorganisms in the water, in which the rats were drowned and kept immersed, and low temperatures of around 5 degrees C during storage, played an important role in the postmortem formation of carbon monoxide.