Fire Victims Research Articles

A rat model of smoke inhalation injury: Influence of combustion smoke on gene expression in the brain

Acute smoke inhalation causes death and injury in victims of home and industrial fires as well as victims of combat situations. The lethal factors in combustion smoke inhalation are toxic gases and oxygen deficiency, with carbon monoxide (CO) as a primary cause of death. In survivors, inhalation of smoke can result in severe immediate and delayed neuropathologies. To gain insight into the progression of molecular events contributing to smoke inhalation sequelae in the brain, we developed a smoke inhalation rat model and conducted a genome-wide analysis of gene expression. Microarray analysis revealed a modified brain transcriptome with changes peaking at 24 h and subsiding within 7 days post-smoke. Overall, smoke inhalation downregulated genes associated with synaptic function, neurotransmission, and neurotrophic support, and upregulated genes associated with stress responses, including nitric oxide synthesis, antioxidant defenses, proteolysis, inflammatory response, and glial activation. Notably, among the affected genes, many have been previously implicated in other types of brain injury, demonstrating the usefulness of microarrays for analysis of changes in gene expression in complex insults. In accord with previously described modulations of nitric oxide homeostasis in CO poisoning, microarray analysis revealed increased brain expression of nitric oxide synthase (NOS) and NOS ligand after inhalation of smoke. Furthermore, immunostaining showed significant elevations in perivascular NOS and in protein nitration, corroborating the involvement of nitric oxide perturbations in post-smoke sequelae in the brain. Thus, the new rat model, in combination with microarray analyses, affords insight into the complex molecular pathophysiology of smoke inhalation in the brain.

Wound Care for Burn Patients in Acute Rehabilitation Settings

Caring for patients who are recovering from severe burns is not common in most inpatient rehabilitation settings. Nursing challenges include patients' physical and psychological changes and their high care demands. Harborview Medical Center (HMC), a regional Level 1 burn and trauma center in Seattle, WA, accepted these nursing challenges and developed a successful plan of care consistent with current evidence. This article describes HMC's nursing experiences while caring for patients with burns. Our experiences may assist other rehabilitation units that serve burn patients. Says one burn survivor: "Nurses make a huge difference in recovery, as they are there 24 hours a day. It is their touch, their caring, and their listening that aids the patient in his journey from fire victim to burn survivor."

Enhanced fluorescence cyanide detection at physiologically lethal levels: reduced ICT-based signal transduction.

Three water-soluble fluorescent probes have been specifically designed to determine free cyanide concentrations up to physiologically lethal levels, >20 microM. The probes have been designed in such a way as to afford many notable sensing features, which render them unique with regard to signal transduction, photophysical characteristics, and their application to physiological cyanide determination and safeguard. The probes are readily able to reversibly bind free aqueous cyanide with dissociation constants around 4 microM3. Subsequent cyanide binding modulates the intramolecular charge transfer within the probes, a change in the electronic properties within the probes, resulting in enhanced fluorescence optical signals as a function of increased solution cyanide concentration. The ground-state chelation with cyanide produces wavelength shifts, which also enable the probes to sense cyanide in both an excitation and emission ratiometric manner, in addition to enhanced fluorescence signaling. This has enabled a generic cyanide sensing platform to be realized that is not dependent on fluorescent probe concentration, probe photodegradation, or fluctuations in the intensity of any employed excitation sources, ideal for remote cyanide sensing applications. Further, the >600 nm fluorescence emission of the probes potentially allows for enhanced fluorescence ratiometric cyanide sensing in the optical window of tissues and blood, facilitating their use for the transdermal monitoring of cyanide for mammalian safeguard or postmortem in fire victims, both areas of active research.

Application of a NeedlExTM to the Analysis of Light Mineral Oils

Low concentration of volatile organic components (VOC) usually need to be condensed before analyzing them by using gas chromatography (GC). NeedlExTM is a recently developed needle for adsorbing VOC. Gas components are easily adsorbed and condensed while passing through the adsorbents in the needle. This paper describes the successful results of trying to adsorb and analyze light mineral oils by the use of NeedlExTM. They are often used for arson cases. The gas phase of soil containing gasoline, kerosene or gas oil was adsorbed using NeedlExTM, and was analyzed by GC. Through easy procedures, the VOC of their oils were efficiently condensed. Furthermore, NeedlExTM was successfully applied to adsorb and analyze kerosene contained in the clothes of a fire victim by using GC. NeedlExTM was found to be a useful device for the adsorption and analysis of light mineral oils.

Modelling Transboundary Air Pollution in Southeast Asia: Policy Regime and the Role of Stakeholders

Transboundary air pollution, popularly known as the ‘haze’, is a recent but significant environmental crisis in Southeast Asia, and is primarily the result of Indonesian forest fires. We identify that the fundamental motivation behind the practice of clearing forestland with fire by the polluters is economic in nature. We then argue that the major victims of the forest fires and haze are likely to play a vital role in the solution of the problem, at least by motivating the polluters, even if they cannot force them not to pollute. Thus, the polluters and victims can be regarded as the ‘stakeholders’ who would take interest and participate actively in the policy regime. A regional model is developed to analyze and specifically to take account of the states responsible for and affected by the haze. The problems of the affected resident population, the forest industries, and the role of the regional governments are modeled. The model also highlights the importance of key variables in determining the severity of the haze, namely the magnitude of the investment in fire fighting, risk mitigation, and scale of fire operations; including forecasting weather conditions. We argue that optimal policy options should simultaneously satisfy the economic needs of the key stakeholders to be effective.

Pathophysiology of acute lung injury in combined burn and smoke inhalation injury.

In the U.S.A., more than 1 million burn injuries occur every year. Although the survival from burn injury has increased in recent years with the development of effective fluid resuscitation management and early surgical excision of burned tissue, the mortality of burn injury is still high. In these fire victims, progressive pulmonary failure and cardiovascular dysfunction are important determinants of morbidity and mortality. The morbidity and mortality increases when burn injury is associated with smoke inhalation. In the present review, we will describe the pathophysiological aspects of acute lung injury induced by combined burn and smoke inhalation and examine various therapeutic approaches.

Chasing the Silver Bullet: U.S. Air Force Weapons Development from Vietnam to Desert Storm (review)

Reviewed by: Chasing the Silver Bullet: U.S. Air Force Weapons Development from Vietnam to Desert Storm Wayne Thompson Chasing the Silver Bullet: U.S. Air Force Weapons Development from Vietnam to Desert Storm. By Kenneth P. Werrell. Washington: Smithsonian Books, 2003. ISBN 1-58834-116-X. Photographs. Notes. Index. Pp. vi, 346. $37.95. Kenneth Werrell's Chasing the Silver Bullet enhances his well-deserved reputation as an astute historian of air power technology. A former U.S. Air Force pilot with a doctorate in history from Duke University, Werrell has written books about air defenses, cruise missiles, and bomber operations. This time he uses declassified documents to discuss aircraft, munitions, and sensors deployed by the U.S. Air Force during the quarter century spanning the Vietnam War and the Gulf War. He tells more about the evolving strengths and weaknesses of each weapon than about the bureaucratic, political, and industrial structures that produced the weapons. Separate chapters treat the F-15, the F-16, the A-10, "stealth" (the F-117 and the B-2), precision-guided munitions, strategic airlift (the C-141 and the C-5), command and control aircraft (the E-3 and the E-8), and satellites. The book begins with an assessment of the Air Force's technological problems during the Vietnam War and ends with a more positive (but not entirely glowing) account of how well the Air Force's new weapons performed in the Gulf War. Werrell is wary of giving air power too much credit for defeating an inept Iraqi regime in 1991, and he emphasizes that air power's ability to strike targets with guided bombs had outrun the ability of U.S. intelligence agencies to find key targets. The Air Force that entered the Vietnam War had devoted most of its resources to preparation for a nuclear war against the Soviet Union. For the Rolling Thunder conventional bombing campaign against North Vietnam, the Air Force relied on F-105s designed to carry nuclear bombs. Before introducing laser-guided bombs late in the war, the Air Force could not bomb accurately from altitudes above the reach of most ground fire. Werrell's account makes clear that the Air Force's difficulties in Southeast Asia led toward the technological developments he describes and away from the service's former focus on nuclear operations. Although most of the aircraft shot down during the Vietnam War were victims of ground fire, many Air Force leaders seemed more concerned about the failure of their fighter aircraft to overwhelm enemy fighter aircraft in air-to-air skirmishes. That failure may have been as much a matter of unrealistic pilot training as a lack of superior technology. Nevertheless, air-to-air losses over North Vietnam provided grist for would-be reformers of weapons acquisition. Werrell highlights the work of John Boyd, whose brief combat fighter pilot experience at the end of the Korean War eventually led to an energy maneuverability theory that influenced the design of the F-15 and F-16. Those fighter aircraft turned out to be heavier and less specialized for the air-to-air mission than reformers wanted. Yet the F-15 and the F-16 long remained the best air-to-air and multi-mission fighters in the world. The Air Force Historical Foundation, Gen. (USAF, Ret.) and Mrs. Robert T. Herres, the McDonnell-Douglas Foundation, Boeing, Pratt and Whitney, [End Page 1015] General Electric, and Lockheed all deserve congratulations for giving Kenneth Werrell the financial support and free rein necessary to write so valuable a contribution. Wayne Thompson Arlington, Virginia Copyright © 2004 Society for Military History

Sex determination by PCR analysis of DNA extracted from incinerated, deciduous teeth.

Establishing the biological sex of human remains is a very important part of identifying victims of fire when severe soft tissue destruction has occurred. Deciduous (children's) teeth were exposed to a range of incineration temperatures 100-500 degrees C for 15 minutes. Polymerase Chain Reaction (PCR) amplification was used to identify specific human amelogenin regions. There was successful identification of human biological sex, from deciduous teeth exposed to incineration temperatures of 200 degrees C and below, using standard ethidium bromide gel staining. There was greater sensitivity using fragment analysis by laser induced fluorescence which achieved sex identification from some teeth heated to 400 degrees C.

터널 화재시 물분무노즐에 의해 형성되는 제연수막의 연기층 확산방지성능에 관한 실험적 연구

In case of a fire in road or railway tunnel it is always necessary to keep the escape condition as good as possible. Most of the victims of major fires in tunnels are because they couldn't leave the tunnel in time and were trapped by smoke, or rescue teams couldn't reach the place of the accident due to low visibility and high temperature. In spring 2003 a comprehensive field experiment was undertaken in a large scaled tunnel in Youngin City to test the effectiveness of a new water spray curtain system, designed to the air qualify inside of a tunnel in case of fire during passenger's escape to safe routes, In order to control the smoke propagation, fixed water sprayed nozzles were used to make water curtain system, which can be installed or hanging water piping line below ceiling. The experiment was accompanied by an extensive measurement campaign in order to measure temperature dropping effect and flow conditions as well as CO concentration for various water sprayed curtains produced by sprinkler heads or water spray nozzle. Eventually comparison analysis were undertaken to investigate the performance of water curtains under fixed water pressure. Therefore most effective water curtain system was presented on the basis of water droplet size in long tunnel.

Intramuscular bleeding of the tongue in the victims of house fire

Intramuscular bleeding of the tongue is frequently observed in autopsy cases of house fire victims. The meaning of this finding has not yet been fully discussed. We examined 69 autopsy cases of house fire victims and investigated several factors contributing to intramuscular bleeding of the tongue. Victims comprised 45 males and 24 females, ranging in age from 1 to 95 years old. Sixty-four cases (93%) involved severely charred bodies, while the remaining five bodies displayed slight burns. Factors studied were age, sex, posture of the body at the scene of the fire, degree of burn injury and carboxyhemoglobin (CO-Hb) levels in blood. CO-Hb level proved to be the only factor relevant to intramuscular bleeding of the tongue. Of 69 autopsy cases, 23 (33%) demonstrated intramuscular bleeding of the tongue (13 cases of slight bleeding, ten cases of severe bleeding). Low concentrations of CO-Hb (≤30%) were observed in six of ten cases (60%) with severe intramuscular bleeding. Of 46 cases without intramuscular bleeding, ten (22%) displayed low concentrations of CO-Hb. These results may indicate that severe burn injuries occurring before inhaling air containing high levels of carbon monoxide represent the cause of intramuscular bleeding of the tongue in fire victims. The burned regions of the body in the early stage of the fire process were unclear due to severe charring in most victims. However, asphyxiation due to neck compression is known to often induce intramuscular bleeding of the tongue. Lack of skin elasticity following burns, particularly in the neck, might act in a similar manner to asphyxial neck compression. In conclusion, intramuscular bleeding of the tongue in fire victims may occur as a vital reaction to burns.

An analysis of fatal unintentional dwelling fires investigated by London Fire Brigade between 1996 and 2000

London is a large capital city with a population of approximately seven million people. It shares many problems with other large cities around the world, including deaths due to fire. Many of these fire deaths can be linked to social problems such as poor housing, loneliness, illness, etc. Data from the London Fire Brigade Real Fire Library—a unique database of information collected from real fire incidents by dedicated teams of fire investigators operating in the Greater London Area has been used to obtain a range of statistics about fatal fires and fire death victims for the 5-year period from 1996 to 2000. Most deaths occurred in unintentional dwelling fires. The statistical information has therefore been analysed to identify the main factors involved as to why people die in unintentional dwelling fires and see what lessons can be learnt from these deaths. Common risk factors identified in the unintentional dwelling fire deaths investigated include smoking, alcohol, old age, disability, illness, living alone, social deprivation and not having a working smoke alarm fitted. Comparisons are also made with the results found from other studies and measures for preventing unintentional dwelling fire deaths are examined.

Chemical factors affecting the interpretation of blood cyanide concentrations in fire victims

The purpose of this study was to examine the effects of methemoglobinemia caused by fire gases on blood cyanide concentrations in fire victims. Twenty-two fire victims with postmortem intervals of 8–48 h were involved. Blood cyanide concentrations at the time of death ( C 0) were estimated using the formula: C 0=C e 0.046t ( C=blood cyanide concentration detected at autopsy, 0.046=first-order rate constant of cyanide disappearing from blood in corpses, and t=postmortem interval). Total (free and combined with cyanide) methemoglobin (MetHb) content was used to estimate the maximum capacity of MetHb for combining cyanide. Blood cyanide concentrations at the time of death were very high (5.32–6.47 mg/l) in five victims. Three showed high saturation (54.7–63.0%) of carboxyhemoglobin (CO-Hb) and elevated total MetHb contents (2.6–5.0%). MetHb at these levels is capable of scavenging up to 8.6–11.4 mg/l of blood cyanide. Thus, blood cyanide might have been completely combined with MetHb at the time of their death. In the remaining two victims, CO-Hb saturation was not high (30.9 and 37.9%) and no free MetHb was detected. As a result they may have exhibited severe toxic effects of cyanide at the time of their death. Our results indicate that MetHb contents and CO-Hb saturation should be determined to evaluate the toxic effects of cyanide in fire victims.

Partial posttraumatic stress disorder revisited

Background: It is thought that the decision rule for a positive diagnosis of Posttraumatic Stress Disorder (PTSD) may be too restrictive, leaving too many victims of a trauma out in the cold for care, compensation, etc. Several authors have proposed the concept of Subthreshold or Partial PTSD (PPTSD). This concept considers that a subject may present a number of symptoms below threshold for criteria C or D (subthreshold syndromes) and may even present without any symptom for one or more of the criteria B, C and D (partial syndromes). Method: Data have been collected by means of the Composite International Diagnostic Interview (CIDI) PTSD-module, in a group exposed to two different traumatic events (130 fire victims and 55 car accident victims). The syndrome patterns has been assessed by means of hierarchical class analyses. Each of the criteria B, C and D has been analyzed separately, showing the symptom patterns as hierarchically order clusters. Results: Depending on the threshold used for criterion C (i.e. 3 or 2 symptoms), 18.4 and 22.7% of the subjects respectively satisfy the criteria for PTSD. 8.7% of the subjects show subthreshold syndromes. 60.7% of the subjects show partial syndromes and 16.7% of the subjects have partial syndromes while fulfilling criterion F, i.e. a clinically significant impairment in functioning. Conclusions: The results show a considerable number of partial and subthreshold syndromes. It is argued that subthreshold syndromes and partial syndromes, which fulfill criterion F, should be regarded as specific nosological categories or as specified PTSD subcategories, i.e. subsyndromal or partial PTSD.

Value of lactic acidosis in the assessment of the severity of acute cyanide poisoning.

To test the hypothesis that plasma lactate concentrations could be of confirmatory value in patients with histories consistent with acute pure cyanide poisoning because immediate laboratory confirmation of suspected cyanide poisoning is rarely possible and because clinicians must rapidly decide whether to administer specific antidotes, which may have severe side effects. Retrospective clinical study. An intensive care unit in a university-affiliated teaching hospital. All acute cyanide-poisoned patients admitted to our intensive care unit, excluding fire victims, from 1988 to 1999. None. Eleven patients were studied. Before antidotal treatment, the median plasma lactate concentration was 168 mg/dL, the median blood cyanide concentration was 4.2 mg/L. Using Spearman's test, there was a significant correlation between plasma lactate and blood cyanide concentrations ( =.74, =.017). Before antidotal treatment, plasma lactate concentration correlated positively with anion gap and inversely with systolic blood pressure, spontaneous respiratory rate, and arterial pH. During the course of cyanide poisonings, a plasma lactate concentration of >or=72 mg/d/L (8 mmol/L) was sensitive (94%) and moderately specific (70%) for a toxic blood cyanide concentration (>or=1.0 mg/L). The specificity was substantially improved in patients not receiving catecholamines (85%). The immediate and serial measurement of plasma lactate concentrations is useful in assessing the severity of cyanide poisoning.

Rapid quantitation of cyanide in whole blood by automated headspace gas chromatography

Cyanide (CN), a chemical asphyxiant, is a rapidly acting and powerful poison. We have developed a sensitive, rapid, simple, and fully automated method for measuring CN in whole blood. The assay is based on the use of gas chromatography (GC) with nitrogen–phosphorus detection and acetonitrile as an internal reference. Following the automated addition of phosphoric acid to the blood sample, the released hydrogen cyanide is analyzed using a fully automated headspace GC system. The assay, validated on human blood samples spiked with potassium cyanide and on clinical samples from fire victims who had smoke inhalation injury, can detect CN at a wide range of concentrations (30–6000 μg/l) in about 17 min (including incubation and GC run time, and <2 min for manual sample preparation). This automated, high-throughput, simple, and sensitive method is suitable for the rapid diagnosis of CN in clinical and forensic specimens.

Toxicity of Fire Smoke

This review is an attempt to present and describe the major immediate toxic threats in fire situations. These are carbon monoxide, a multitude of irritating organic chemicals in the smoke, oxygen depletion, and heat. During the past 50 years, synthetic polymers have been introduced in buildings in very large quantities. Many contain nitrogen or halogens, resulting in the release of hydrogen cyanide and inorganic acids in fire smoke as additional toxic threats. An analysis of toxicological findings in fire and nonfire deaths and the results of animal exposures to smoke from a variety of burning materials indicate that carbon monoxide is still likely to be the major toxicant in modern fires. However, the additional toxic threats mentioned above can sometimes be the principal cause of death or their addition can result in much lower than expected carboxyhemoglobin levels in fire victims. This analysis also revealed that hydrogen cyanide is likely to be present in appreciable amounts in the blood of fire victims in modern fires. The mechanisms of action of acute carbon monoxide and hydrogen cyanide poisonings are reviewed, with cases presented to illustrate how each chemical can be a major contributor or how they may interact. Also, lethal levels of carboxyhemoglobin and cyanide in blood are suggested from an analysis of the results of a large number of fire victims from different fire scenarios. The contribution of oxygen depletion and heat stress are more difficult to establish. From the analysis of several fire scenarios, they may play a major role in the room of origin at the beginning of a fire. The results in animal studies indicate that when major oxygen depletion (<10%) is added to lethal or sublethal levels of carbon monoxide or hydrogen cyanide its major role is to substantially reduce the time to death. In these experiments the carboxyhemoglobin level at death was slightly reduced from the expected level with exposure to carbon monoxide alone. However, blood cyanide was reduced by a factor of ten from the expected level with exposure to hydrogen cyanide alone. This is another factor (among many other presented) complicating the task of establishing the contribution of cyanide in the death of fire victims, from its analysis in their blood. Finally the role of ethanol intoxication, as it may influence carboxyhemoglobin levels at death, is reviewed. Its role is minor, if any, but the data available on ethanol in brain tissue and blood of fire victims confirmed that brain ethanol level is an excellent predictor of blood ethanol.

Pre- and post-disaster negative life events in relation to the incidence and severity of post-traumatic stress disorder

There is evidence suggesting that stressful life events may precede major psychiatric illness, such as major depression, and that the severity of a traumatic event outside the range of usual human experience may provoke post-traumatic stress disorder (PTSD). The present study was carried out to examine the effects of pre- and post-disaster stressful life events on the incidence rate of PTSD following two man-made traumatic events. An epidemiological study examining 127 victims of a flash fire in a ballroom and 55 motor vehicle accident (MVA) victims was undertaken. PTSD symptoms were assessed by means of the Composite International Diagnostic Interview and the pre- and post-disaster stressful life events by means of the Diagnostic Interview Schedule, Disaster Supplement. Binary logistic and multiple linear regression analyses were employed to examine the relationships between PTSD and pre- and post-disaster life events. There were no significant relationships between stressful life events the year prior to the traumatic event and the incidence or severity of PTSD. There were highly significant relationships between the cumulative number and event severity of post-disaster negative life events and the incidence rate and severity of PTSD. The post-disaster life events were significantly more related to the avoidance–depression dimension than to the anxiety–arousal dimension of PTSD. The most significant life events were: loss of job or income, broken relationships, serious illnesses or injuries in the victims and death or illness in close acquaintances. The results of this study show that the number and severity of additional stressful life events signal a higher risk to develop PTSD and a higher severity of the avoidance–depression dimension of PTSD symptomatology.

Postmortem serum uric acid and creatinine levels in relation to the causes of death

Serum uric acid (UA) and creatinine (Cr) mainly derive from skeletal muscle tissues. Although, remarkable postmortem stability of the serum levels has been reported, there appears to be very poor knowledge of the diagnostic value in investigation of death, except for uremia. The aim of the present study was to evaluate postmortem serum UA and Cr levels using 395 forensic autopsy cases, in comparison with blood urea nitrogen (BUN), for investigation of the pathophysiology of death with special regard to the causes of death involving possible skeletal muscle damage, e.g. due to hypoxia, heat or agonal convulsions. Cr and BUN showed relatively good topographic stability in the cadaveric blood, whereas, UA was often much higher in the right heart blood than in the left heart and peripheral blood, independent of postmortem intervals. Moderate to marked elevation of Cr and BUN accompanied with hyperuricemia was observed in delayed death. In the acute death cases (survival time <30 min), UA, especially in the right heart blood, showed a considerable elevation in mechanical asphyxiation and drowning. The Cr level in fire victims with a lower carboxyhemoglobin (COHb) level (<60%) was significantly higher than in those with the possible fatal level (>60%). A similar elevation of Cr was observed in fatalities from heat stroke and methamphetamine (MA) poisoning. The observations suggested that hyperuricemia in acute death may be indicative of advanced hypoxia and that elevated Cr level may reflect the skeletal muscle damage, especially due to thermal influence.

Potential for Error when Assessing Blood Cyanide Concentrations in Fire Victims

The present study explores toxicologic significance of blood cyanide concentrations in fire victims. Headspace gas chromatography was used for cyanide detection. Analysis of blood samples from ten fire victims (postmortem interval = 8 h to 3 to 5 d) detected zero to 11.9 mg/L of cyanide and a large difference in cyanide concentrations among victims. Carboxyhemoglobin (COHb) saturation was in the range of 24.9 to 84.2%. To examine the effects of methemoglobinemia and postmortem interval on blood cyanide concentrations in fire victims, an experiment was carried out using rabbits as the animal model. The rabbits were sacrificed by intramuscular injection of 1 mL/kg 2% potassium cyanide 5 min after intravenous injection of 0.33 mL/kg of 3% sodium nitrite (Group A, n = 3) or physiological saline (Group B, n = 6). Average methemoglobin contents immediately before potassium cyanide administration were 6.9 and 0.8% in Groups A and B, respectively. Average cyanide concentrations in cardiac blood at the time of death were 47.4 and 3.56 mg/L, respectively. When blood-containing hearts of the rabbits (n = 3 for Group B) were left at 46 degrees C for the first 1 h, at 20 to 25 degrees C for the next 23 h and then at 4 degrees C for 48 h, approximately 85 and 46% of the original amounts of blood cyanide disappeared within 24 h in Groups A and B, respectively. After the 72-h storage period, 37 and 10%, respectively, of the original amounts of cyanide remained in the blood. When the other three hearts in Group B were left at 20 to 25 degrees C for the last 48 h without refrigeration, cyanide had disappeared almost completely by the end of the experiment. The present results and those published in the literature demonstrate that the toxic effects of cyanide on fire victims should not be evaluated based solely on the concentration in blood.

Hydrogen cyanide and carbon monoxide in blood of convicted dead in a polyurethane combustion: a proposition for the data analysis

Carbon monoxide is a well-known toxic component in fire atmospheres. However, the importance of hydrogen cyanide as a toxic agent in fire causalities is under discussion. A tragic polyurethane mattress fire provoked death of 35 convicts in a prison (Unit I, Olmos, Penitenciary Service of Buenos Aires Province, Argentina), in 1990. There is no report of any investigation carried out with such a large amount of victims in Argentina. Carboxihemoglobin (COHb) and hydrogen cyanide (HCN) were quantified in victims blood to elucidate the cause of the death. Saturation of COHb ranged between 4 and 18%, and HCN 2.0–7.2 mg/l. These latter values were higher than the lethal levels reported in literature. Other toxic components routinely measured (ethanol, methanol, aldehydes and other volatile compounds) gave negative results on the 35 cases. Neither drugs of abuse nor psychotropics were detected. Statistical χ 2 analysis was applied to find differences between HCN and COHb concentrations. Saturation of COHb and HCN in blood were not independent variables ( χ 2=8.25). Moreover, the ratio COHb/HCN was constant (0.47±0.04). In order to evaluate the contribution of each toxic to the diagnosis, a lethal index was defined for each toxic (LI CO and LI HCN). The most probable cause of death could be inferred by a suitable plot of both indexes. The results indicated that death in the 35 fire victims was probably caused by HCN, generated during the extensive polyurethane decomposition provoked by a rapid increase of temperature.