1. Carbon Monoxide Oximetry

2. Course Objectives
Define carbon monoxide and carbon monoxide poisoning.
Describe the causes of carbon monoxide poisoning.
Identify signs and symptoms of carbon monoxide poisoning.
Describe the BLS care and treatment for a patient suffering carbon monoxide poisoning.

3. Course Objectives- cont’d
Describe the steps needed to properly identify carbon monoxide poisoning using a CO Oximeter
Describe how to identify false readings of a CO Oximeter
Identify the risks of carbon monoxide poisoning to EMS providers and firefighters

4. Course Objectives- cont’d
Describe the danger(s) in treating and releasing (not transporting) a patient with a signficant carbon monoxide exposure

5. A-EMT Course Objectives (in addition to BLS objectives)
Describe when IV therapy and advanced airway procedures may be needed in a patient with carbon monoxide poisoning.

6. Paramedic Course Objectives (in addition to EMT-B and A-EMT objectives)
Describe advanced life support procedures that may be needed in a patient with carbon monoxide poisoning.

7. Key Vocabulary Carbon monoxide Carboxy-hemoglobin Concentration
Duration
Half-life
Hemoglobin
Hydrocarbon
Hyperbaric oxygen treatment (HBO)

8. Key Vocabulary (continued)
Hypoxia
Imitator
Impairments
Incomplete combustion
Liquefaction
Mimic
Molecules
Parts per million (PPM)

9. Key Vocabulary (continued)
Pathophysiology
Physiological
Poisoning
Red blood cells
Suffocation
Tissue hypoxia
Transcutaneous

10. Carbon Monoxide Poisonings
5,000 fatalities annually in US
10’s of thousands poisonings annually in US
Most common cause of accidental postings deaths for decades

11. What is Carbon Monoxide?
Colorless
Odorless
Tasteless
“Silent killer”
“Great Imitator”
Measured in parts per million or PPM

12. Carbon Monoxide: Translating PPM to SpCO
PPM or “Parts Per Million” is the atmospheric concentration of the gas.
PPM is a common fire ground safety measurement, often misleading as CO forms in pockets.
SpCO as measured by a CO Oximeter is a function of PPM CO and total time of exposure to the poison.
Age and health may be a factor.
Even low PPM levels can lead to high SpCO if exposure is long enough; common in overhaul after a fire.
Even at 50 PPM for 60 minutes- requires assessment and possible medical treatment with oxygen.

13. “PPM CO” x “Exposure time” = SpCO

14. Causes of Carbon Monoxide
Incomplete combustion of wood, or by hydrocarbon products such as:
Home heating oils
Charcoal
Kerosene
Coal
Gas

15. Common CO Poisoning Sources
Faulty furnaces, heaters
Auto exhaust
Gas generators
Charcoal grills used indoor
Tobacco smoke
Fires
Small gas engines or equipment
Gas appliances
Gas heaters in enclosed area

16. An Idaho example…….
“A family of eight people nearly died Sunday night, after using a charcoal grill to heat their trailer home. Owyhee County Deputies arrived to the home after a frantic call from one of the women inside the house. All eight including five children were taken to an area hospital and treated for Carbon Monoxide poising. Investigators say the family is doing fine, but lucky to be alive.”
Idaho Press Tribune, 2007

17. Carbon monoxide pathophysiology overview
Carbon monoxide is inhaled and passed from the lungs to the blood binding to hemoglobin.
Produces carboxyhemoglobin.
Affinity to hemoglobin 250 X greater than oxygen.
Reduces oxygen carrying capacity of blood.
Alters release of remaining oxygen to cells.
Acts as an intracellular toxin.
Poisons cells and tissue.

18. Carbon monoxide pathophysiology overview- cont’d
Binds with myoglobin in muscle.
Interferes with heart and skeletal muscle.
Immediate threat to life.
Oxygen starvation.
Cardiac arrhythmias.
Alters judgment, reasoning.

19. Carbon monoxide pathophysiology overview- cont’d
Long-term health effects
Central nervous system damage.
Cardiovascular damage.

20. Where does oxygenation take place?
Blue dots represent carbon dioxide, white dots represent oxygen.
Oxygen enters through the lungs and is exchanged with carbon dioxide at the alveoli.
During CO poisoning, oxygen cannot bind to the hemoglobin (no room at the inn theory)

21. Another example of oxygenation
Oxygen is carried from the lungs by the blood hemoglobin to the tissues; here the beating heart is shown, and normal healthy oxidative metabolism goes on.
During Carbon Monoxide poisoning, CO is carried from the lungs by the blood hemoglobin to the tissues, preventing oxygen from being carried, and blocking normal oxidative metabolism. Note how slowly and weakly the heart is beating, since it is starved for oxygen (i.e.. blue in color).

22. How does CO prevent oxygenation of tissues?
Normal oxygenation of the hemoglobin molecule. As it goes from (deoxy)hemoglobin to oxyhemoglobin the color changes from blue, as in venous blood, then to pink, as in arterial blood.
Here carbon monoxide (CO) enters the picture, and through its very high affinity for hemoglobin, displaces the oxygen from the hemoglobin. This prevents oxygen being carried to the tissues and organs of the body. Carboxyhemoglobin is reddish in color.

23. Factors That Affect Severity
Amount of carbon (concentration)
Time (duration)
Activity level (during exposure)
Health
Age

24. Who is High Risk? Specific Occupations (fire & EMS) Elderly Children
Infants
Pregnant mothers
Unborn children
People with existing health problems

25. Signs & Symptoms Headache Dizziness Weakness Nausea Vomiting
Chest pain
Altered LOC
Flu-like

26. Signs & Symptoms (continued)
Suspect CO poisoning when:
Several symptoms are reported at same time
No other cause can be identified
More than one person at scene reports similar symptoms

27. Nervous System Effects
Effects may mimic a stroke
Brain death
Long term neurological effects may result

28. Cardiovascular System Effects
Hypotension
Clotting disorders
Dysrhythmia’s
Symptoms may mimic MI

29. Detection for EMS responders
CO Oximetry: non-invasive method of detecting carbon monoxide in patients
CO-oximeter (example: Massimo Rad-57)
Detects carboxyhemoglobin levels
Detects oxyhemoglobin levels
Obtains pulse rate
Small, handheld battery operated
Finger clamp similar to a pulse ox
Pulse oximeters cannot detect CO

30. Treatments: Scene Safety 1st!
Rescuer safety is #1 priority
Never enter a hazardous scene without PPE and proper respiratory support
Remove the patient from the hazardous environment as quickly as possible- don’t become a victim!
Follow local protocols

31. BLS Treatment Remove patient from environment Apply high-flow oxygen
Obtain SAMPLE history
Complete an assessment
Obtain vital signs
Use CO-oximeter if available to confirm CO poisoning suspicion
Transport to most appropriate facility

32. ALS Treatment Evaluate respiratory system IV
Re-assess LOC & vital signs
Evaluate respiratory system IV
EKG monitoring- every patient with suspected CO poisoning should receive EKG monitoring
Use CO-oximeter if available
Transport to most appropriate facility

33. Specialized Treatment
Hyperbaric oxygen treatment or HBO may be recommended. This is still a somewhat controversial treatment as the true reasons behind patient improvement are not well understood.
Hyperbaric facts- Patients undergoing hyperbaric treatment are placed in a chamber where 100% oxygen is circulated. The oxygen is pressurized so that air pressure may be 2-3 times greater than normal. Some theorize this allows the lungs and skin to absorb more concentrated oxygen in a shorter period of time.
Hyperbaric oxygen accelerates the clearance of CO from the body, restoring oxygen delivery and preventing toxic effects on the central nervous system and blood vessels.
Follow local protocols for guidance

34. A typical SpCO triage algorithm
Measure SpCO
0-3%
>3%
No further medical evaluation of SpCO needed
Loss of consciousness, altered mental status or SpCO >25%
Yes No
Transport on 100% oxygen for ED evaluation. Consider transport to hospital with hyperbaric chamber
SpCO >12
SpCO < ? (determined by local protocol)
Transport on 100% oxygen for ED evaluation
Symptoms of CO exposure?
Course of action determined by local protocol

35. Pitfalls for responders to be aware of-
Responders should be very cautious with “treat and release” on patients with CO exposure due to potentially long half life.
Moderate to high readings should ALWAYS be confirmed on more than one finger (2 minimum, 3 is preferred).
Patients who are extremely cold or have “club nails” may produce a false reading.

36. Conclusion
Consider CO poisoning when symptoms seem suspicious or vague or if the patient has been in an enclosed environment with identified signs/symptoms.
Early recognition and treatment and transport to a hospital are critically important in saving the patient and preventing others from being poisoned as well.