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Carbon Monoxide Exposure
Carbon monoxide is the most common cause of poisoning in industrialized countries, including
the United States. Fire department (FD) personnel are often the first to encounter victims of carbon monoxide poisoning. In
addition, because of the nature of the profession, firefighters are at increased risk of occupational exposure to carbon monoxide.
In this presentation we will review the chemistry, incidence, pathophysiology, detection,
long-term effects, and treatment of carbon monoxide poisoning. There will be an emphasis on new technologies that now allow
the diagnosis and monitoring of patients exposed to carbon monoxide in the prehospital setting. In addition, we will investigate
the incidence and significance of combination poisonings with cyanide and carbon monoxide.
Exogenous Sources
Certainly, most CO exposure is related to exogenous causes. Among these are house fires,
automobile exhaust fumes, fumes from propane-powered vehicles (e.g., forklifts), heaters, indoor stoves, camp stoves, boat
exhaust fumes, gas-powered electrical generators, cigarette smoke, and smoke from charcoal-fired cook stoves and ovens. Essentially,
any combustible item should be considered a possible source of CO. Methylene chloride is an organic hydrocarbon consisting
of two hydrogen atoms and two chloride atoms bound to a carbon atom. It is often used as an industrial solvent, particularly
as a paint remover and adhesive remover. Methylene chloride is converted to CO in the liver after inhalation. Persons exposed
to high levels of methylene chloride can develop carboxyhemoglobinemia and the signs and symptoms of CO toxicity.
Typically, following CO exposure, there will be a phase of decreased oxygen levels in the
blood (hypoxemia). This is usually followed by a period of re-oxygenation when the victim is removed from the toxic environment
and oxygen administered. It also occurs when carboxyhemoglobin is broken down and replaced with normal hemoglobin. The effects
of CO-mediated hypoxemia are dependent upon any underlying disease that might be present (such as emphysema or heart disease).
These periods of hypoxemia often result in the formation of dangerous chemicals called free radicals. Free radicals are highly
reactive chemical compounds and can cause significant damage to the cells of the body. An increase in free radical compounds
results in what is known as oxidative stress. Oxidative stress can injure cells, tissues, or organs and is associated with
the development of many diseases including atherosclerosis, Parkinson’s disease, Alzheimer’s disease, and several
other chronic disease processes. Thus, oxidative stress can cause injury to oxygensensitive tissues, such as the brain and
the heart, beyond those caused by the initial hypoxemic insult. 
A phenomenon called delayed neurologic syndrome (DNS) has been identified as a complicationof
acute and chronic CO poisoning. In DNS, recovery from the initial CO poisoning is seemingly apparent only to have the victim
develop behavioral and neurological deterioration anywhere from 2–40 days later. The true prevalence of DNS is uncertain
with estimates ranging from 1–47% after CO poisoning. It is clear that patients who have more CO poisoning-related symptoms
initially appear more apt to develop DNS. In addition, DNS is more common when there is a loss of consciousness in the acute
poisoning. DNS has also been reported in children. Scientific studies are mixed as to whether hyperbaric oxygen therapy prevents
DNS. Other neurologic complications, such as Parkinsonism, have been reported with DNS. Information Provide by the International Association of Firefighters  
New National Standard for CO Screening by Pulse CO-OximetryTM 2008 NFPA 1584 establishes
the routine use of Pulse CO-Oximetry
as a way to protect the lives of the nation’s firefighters from the dangers of CO
Poisoning Irvine, California – February 14, 2008 – Masimo (NASDAQ: MASI), the inventor of Pulse COOximetry and
Measure-Through Motion and Low Perfusion pulse oximetry, announced today that the National Fire Protection Association (NFPA)
has made Carbon Monoxide (CO) screening by Pulse COOximetry a new national healthcare standard for firefighters potentially
exposed to Carbon Monoxide poisoning. NFPA’s consensus codes and standards serve as the worldwide authoritative source
on fire prevention and public safety—with virtually every building, process, service, design, and installation in society
today is affected by NFPA documents.
The new standard, which became effective December 31, 2007 and was published on January
31, 2008, establishes that “any firefighter exposed to CO or presenting with headache, nausea, shortness of breath,
or gastrointestinal symptoms” must be measured for CO poisoning by Pulse CO-Oximetry or other available methods. It
also requires every fire department to establish Standard Operating Guidelines (SOGs) that outline uniform rehabilitation
procedures for firefighters at incident scenes and training exercises.
Too often, even the most skilled first responders miss the chance to treat carbon monoxide
poisoning early because, until Masimo invented Masimo Rainbow SET Pulse CO-Oximetry in 2005, there wasn’t a noninvasive
way to detect elevated levels of CO in the blood. With the Masimo Rad-57 Pulse COOximeter, fire fighters, EMS professionals
and ER clinicians can easily detect carbon monoxide poisoning by applying a noninvasive LED-based sensor on the victims or
themselves, allowing for prompt and possibly life-saving treatment that can also limit the likelihood of long-tern cardiac
and neurological damage.
Studies have shown that even a single high level exposure, or prolonged exposure to low
levels of CO, has the potential to cause long-term heart, brain and organ damage. Long-term effects of CO include: cardiac
arrests, Parkinson-syndromes affecting motor skills and speech,
dementia, cortical blindness, acute renal failure, and muscle cell death.
On March 6, 1987, at 0103 hours, the Kitchener Fire Department responded to a structure
fire at a local industry called Horticultural Technologies Incorporated (Incident No. 0295). Upon the arrival of the first
pumper, (P-4) commanded by Captain Edward (John) Stahley, the fire had almost entirely consumed the interior of the manufacturing
area of the structure and was about to break through the roof. As the fire progressed, multiple alarms were called, which
lead to all units in the City being committed to the fire (with the exception of Pump 2 and Aerial 2).
The fire progressed through the night into the next morning with the night shift being relieved by the day shift. In total,
approximately 69 fire fighters participated in the fighting of this fire. This works out to be approximately one half of the
Kitchener Fire Department's Fire Suppression Division at the time. Members of the Waterloo Regional Police Service and Kitchener-Waterloo
Regional Ambulance Service were also in attendance.
Those at the scene reported "smoke and flame that was every colour of the rainbow". This and the presence of a large number
of 45 gallon drums around the perimeter of the building caused some initial concerns as to what was contained in the plant.
The manager of the facility was called, but lived in Mississauga and took over one hour to arrive. He did not provide much
information, other than to explain that they manufactured items for the floral industry, primarily something called "Oasis
Floral Foam", which is a hard foam like substance used by florists to hold floral arrangements in place as well as keeping
the arrangement moist.
A green dye was used in the manufacturing process, which caused a number of fire fighters to take on a green tinge as they
were fighting the fire. As the aforementioned caused some initial concerns, each member was requested by the KPFFA Health
and Safety Committee to complete a KPFFA Exposure Report Form and a City of Kitchener Accident Report indicating on each that
they had a "possible exposure to a hazardous substance" as a result of their attendance at this fire.
There were no significant injuries that resulted from the fire at the time, other than Captain Ed Stahley who did attend the
Emergency Room at Kitchener-Waterloo General Hospital for an examination because he had turned a greenish colour. He was given
a clean bill of health at that time. No further action was taken regarding this fire and all the reports completed by our
members were filed away.
Fire Fighter Henry Lecreux was diagnosed as having developed Parkinson's Disease but continued to work for some months, until
his condition worsened so that he was no longer able to speak and/or move properly and was forced on to sick leave. Henry's
condition continued to decline until he passed away in February of 1993 at age 52. The cause of death was listed as toxic
shock as a complication of Parkinsons Disease.
In addition to the aforementioned, an unnamed retired Fire Fighter, who also attended the Horticultural fire has also developed
Parkinsons Disease.
Others who attended the fire have experienced a myriad of medical problems. One of the Platoon Chiefs on duty at the fire
retired early with a number of medical problems. Platoon Chief Jim Loree, Captains Roy Hartman and Jim Klaehn have all suffered
heart attacks since the fire and retired. These fire fighters have indicated that they do not wish to file claims and Jim
Loree has subsequently passed away.
Captain Jim Rebbeck (retired) was diagnosed with what was believed to be Parkinson's Disease a few years ago. Captain Rebbeck
is the only one of the aforementioned who have pursued a claim with the Board. With this claim there is some conflicting information
as to the actual diagnosis, but he definitely suffers from an illness related tremors.
Upon closer examination, this has all happened to a group of approximately 69 fire fighters that attended this fire at one
point or another. As stated previously, this works out to be approximately one half of the department at the time and in essence
this has provided us with a control group to compare to. One half of the department was there and the other half was not.
All of the aforementioned illnesses happened to those who were at the fire.
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