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European Survey: Risk of Cyanide Poisoning in Smoke Inhalation

European Survey: Risk of Cyanide Poisoning in Smoke Inhalation, Symptoms, Key Treatment and Outcome (RISK)

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT01386788
Acronym
RISK
Enrollment
102
Registered
2011-07-01
Start date
2009-04-30
Completion date
2012-07-31
Last updated
2016-09-28

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Smoke Inhalation Patients

Keywords

Smoke, cyanide, closed space fires

Brief summary

Cyanide poisoning is commonly viewed as a rare but dramatic event, occurring in industrial or laboratory settings as the result of accidental releases of hydrogen cyanide (HCN) gas (e.g. in the case of fire) or salts in the case of suicide attempts. In fact, cyanide poisoning is considerably more common than is generally appreciated. Multiple clinical and post-mortal studies have demonstrated that HCN contributes to the toxicity of fire smoke. Cyanide acts primarily through its strong affinity for the iron-containing heme moiety, binding to numerous critical enzyme systems in the body and rendering them inactive. Of late, increasing attention has been paid to the relationship of cyanide and nitric oxide. The interactions appear to be complex, with cyanide inducing nitric oxide production by binding to N-methyl-D-aspartate (NMDA) receptors, as well as binding to nitric oxide synthase. The latter may be overcome by the presence of nitric oxide synthase inhibitors. Probably, the majority of the cyanide poisoning cases are due to smoke inhalation in closed-space fires. So far, there are no clear data available on the prevalence of cyanide poisoning in smoke inhalation. This information would be of great interest for all emergency physicians since a proven or supposed cyanide poisoning does not only requires an intensive supportive care, including the administration of supplemental oxygen and artificial ventilation, blood pressure support, and anticonvulsants, but also a rapid administration of a cyanide antidote. Therefore, it is the goal of this survey to assess the prevalence of cyanide poisoning in smoke inhalation victims. Only the data of patients with a cyanide measurement before specific antidote treatment will be included

Detailed description

Cyanide poisoning is commonly viewed as a rare but dramatic event, occurring in industrial or laboratory settings as the result of accidental releases of hydrogen cyanide (HCN) gas (e.g. in the case of fire) or salts in the case of suicide attempts. In fact, cyanide poisoning is considerably more common than is generally appreciated. Multiple clinical \[1-4\] and post-mortal studies \[5-10\] have demonstrated that HCN contributes to the toxicity of fire smoke. Cyanide acts primarily through its strong affinity for the iron-containing heme moiety, binding to numerous critical enzyme systems in the body and rendering them inactive \[11\]. Of late, increasing attention has been paid to the relationship of cyanide and nitric oxide. The interactions appear to be complex, with cyanide inducing nitric oxide production by binding to N-methyl-D-aspartate (NMDA) receptors \[12\], as well as binding to nitric oxide synthase. The latter may be overcome by the presence of nitric oxide synthase inhibitors. Probably, the majority of the cyanide poisoning cases are due to smoke inhalation in closed-space fires. So far, there are no clear data available on the prevalence of cyanide poisoning in smoke inhalation. This information would be of great interest for all emergency physicians since a proven or supposed cyanide poisoning does not only requires an intensive supportive care, including the administration of supplemental oxygen and artificial ventilation, blood pressure support, and anticonvulsants, but also a rapid administration of a cyanide antidote. Therefore, it is the goal of this survey to assess the prevalence of cyanide poisoning in smoke inhalation victims. Only the data of patients with a cyanide measurement before specific antidote treatment will be included.

Interventions

Sponsors

Dr. Ernst MW Koch
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Healthy volunteers
No

Inclusion criteria

* Closed space fire, Soot deposits, Altered mental status * Blood specimen before intravenous antidote treatment (cyanide measurement) * Known delay between end of smoke exposure and blood sampling * Malaise and/or Headache and/or Altered mental status in fire workers

Exclusion criteria

* Pregnancy * Multiple trauma, Blast * Patient pronounced dead at scene without resuscitation attempt * Patient in whom the time elapsed between the end of exposure and blood sampling is greater than 2 hours

Design outcomes

Primary

MeasureTime frameDescription
Overall Survival After 24 Hours24 hoursNumber of participants who survived at 24 hours after smoke inhalation were reported.
Serum Cyanide Levelsblood sampling within 2 hours after smoke inhalation

Countries

Germany

Participant flow

Recruitment details

102 patients were enrolled, data of 100 patients were evaluated

Participants by arm

ArmCount
Smoke Inhalation Victims
Smoke inhalation victims included civil victims and fire workers as specified in the inclusion criteria were observed.
102
Total102

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyLost to Follow-up2

Baseline characteristics

CharacteristicSmoke Inhalation Victims
Age, Continuous49.4 years
FULL_RANGE 19
Sex: Female, Male
Female
39 Participants
Sex: Female, Male
Male
63 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
— / —
other
Total, other adverse events
0 / 0
serious
Total, serious adverse events
0 / 0

Outcome results

Primary

Overall Survival After 24 Hours

Number of participants who survived at 24 hours after smoke inhalation were reported.

Time frame: 24 hours

ArmMeasureValue (NUMBER)
Smoke Inhalation VictimsOverall Survival After 24 Hours96 participants
Primary

Serum Cyanide Levels

Time frame: blood sampling within 2 hours after smoke inhalation

Population: All recruited patients that met all inclusion criteria including blood sampling for cyanide serum level

ArmMeasureGroupValue (NUMBER)
Smoke Inhalation VictimsSerum Cyanide Levels<1.1 mcmol/l25 participants
Smoke Inhalation VictimsSerum Cyanide Levels1.2 - 5 mcmol/l49 participants
Smoke Inhalation VictimsSerum Cyanide Levels>5 - 10 mcmol/l5 participants
Smoke Inhalation VictimsSerum Cyanide Levels>10- 20 mcmol/l7 participants
Smoke Inhalation VictimsSerum Cyanide Levels>20- 40 mcmol/l4 participants
Smoke Inhalation VictimsSerum Cyanide Levels>40- 100 mcmol/l7 participants
Smoke Inhalation VictimsSerum Cyanide Levels>100 mcmol/l3 participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026