The Quick and Dirty Guide to Carbon Monoxide Poisoning
The Most Important Thing: You MUST have a high index of suspicion, especially during the cold months; especially in any enclosed space where the chief complaint is altered mental status or decreased level of consciousness. If you have more than one patient with similar symptoms, this is another big tip. Exposure to CO not only effects them, but it can effect you before you even know it's happening. The FIRST thing to do in suspected carbon monoxide poisoning is to remove yourself and the patients from the environment, then add supplemental oxygen, and transport.
Quick and Dirty Pathophysiology
Oxygen normally hitches a ride on red blood cells and the red blood cells deliver the oxygen to the tissue. Carbon Monoxide is a mean ass bully, and cuts in front of the line, jumping on the red blood cell and not allowing the oxygen to get on. Then the carbon monoxide gets carried to the tissue and the tissue doesn't get enough oxygen. This results in tissue hypoxia and death. This effects all organs of the body, but is not limited to peripheral skin perfusion. This hypoxia effects the brain and causes altered mental status. It also effects the lungs and heart and can cause cardiac dysrhythmias such as ventricular fibrillation.
What is Carbon Monoxide?
Carbon Monoxide is a waste byproduct produced by burning different types of fuel. Carbon monoxide is a colorless, odorless gas. Because it is impossible to see, taste, or smell, the toxic fume can kill you before you are even aware it's in your home. Carbon monoxide poisioning is the most common type of fatal poisoning in the developed world.
Why is there (CO) carbon monoxide instead of (CO2) carbon dioxide?
When there is adequate oxygen supply to the combustion, carbon dioxide is formed. However, when there is inadequate oxygen involved in the combustion or burning of organic matter like natural gas or wood, carbon MONOXIDE is formed. This just means there is only 1 atom of oxygen for each part of carbon instead of two. Carbon dioxide is a normal component of respiration. Carbon MONOXIDE, on the other hand, is lethal, and when taken in by the body, leads to hypoxia and death.
Causes of Carbon Monoxide Poisoning
Carbon monoxide poisoning can happen anywhere there is combustion of organic fuels combined with poor ventilation. Look out for your firefighters who may be exposed during normal firefighting operations in buildings and houses. With potential suicides by CO poisoning, open the garage door. Make sure to search the house or building for ALL patients. Your patient may have an altered mental status and cannot tell you who is in the house. Remember that old people and children will be the first to lose consciousness.
Primary Causes of Carbon Monoxide Poisoning
- Poorly ventilated home using gas heating/cooking
- Attempted suicides where people leave the car running with the garage door closed
- Firefighters inside house or building fires
- Smoking indoors in poorly ventilated enclosed areas
Signs and Symptoms of Carbon Monoxide Poisoning
When its extreme, we all know that exposure causes the cherry-red skin tone, but that's not the only thing we should appraise. The cherry red skin is a LATE sign of exposure. The PRIMARY symptoms of Carbon Monoxide poisoning are weakness, fatigue, and flu-like symptoms to start with. It then progresses to altered mental status, unsteady gait and ataxia (inability to make coordinated movements.) Prolonged exposure to high levels can lead to coma or death. Remember that children and old people are most susceptible to the effects of carbon monoxide poisoning. Pregnant women and their babies are also at a high risk because the fetal hemoglobin has an even higher affinity for CO2.
Progressive Symptoms of Carbon Monoxide Poisoning
- Confusion/Memory Loss
- Nausea and Vomiting
- Abnormal Reflexes
- Difficulty in coordination
- Difficulty in breathing
- Chest pain
- Cerebral edema
Treatment of Carbon Monoxide Poisoning
If you have a device on your truck that checks carbon monoxide levels, use it. Anything higher than 12% requires treatment.
For BLS units, evacuate yourself and the patient, add 100% oxygen via non-rebreather, and transport immediately.
For ALS Units:
- Remove yourself and the patient from the effected area
- Be prepared to intubate or assist ventilations
- Administer normal saline at around 500mL/hour or more en route
- Prepare to deal with seizures - Consider Diazepam 2-10mg
- Perform 12 Lead ECG and - Look for PVCs, heart blocks, ST depression, abnormal T waves, a-fib and v-fib. These are common cardiac issues that are possible with CO poisoning.
- Carbon Monoxide is a mean ass bully, and cuts in front of the line, jumping on the red blood cell and not allowing the oxygen to get on. Then the carbon monoxide gets carried to the tissue and the tissue doesn't get enough oxygen. This results in tissue hypoxia and death.
- The cherry red skin is a LATE sign of exposure. Look for weakness, flu-like symptoms, and altered mental status, especially if there are multiple patients in an enclosed space.
- Make sure to search the house or building for ALL patients, not just conscious patients with a complaint.
- Treatment is primarily supportive care with 100% oxygen, IV fluids, and rapid transport.
Suggested related reading from Medictests.com
The Quick and Dirty Guide to Hypothermia
The Quick and Dirty Guide to Difficulty Breathing
The Quick and Dirty Guide to Acid Base Balance
Other links for further study