Carbon Monoxide Poisoning – Overview and More

Carbon monoxide poisoning occurs when you breathe in too much carbon monoxide (CO), a colorless, odorless gas that is produced when you burn fuel. Symptoms include headaches, dizziness, weakness, vomiting, chest pain, and confusion. Excessive CO exposure can cause serious heart rhythm disturbances, seizures, loss of consciousness, and even death .

Carbon monoxide poisoning is relatively common in the United States, with approximately 20,000 people admitted to emergency departments each year. This can be avoided by installing inexpensive but effective carbon monoxide alarms in your home.

Carbon monoxide poisoning can be diagnosed with a CO oximeter, a non-invasive device that measures CO in the blood. Treatment usually consists of supplying compressed oxygen through a mask without circulation. In severe cases, treatment in a pressure chamber may be necessary .

Get Medical Information / Emily Roberts

Carbon Monoxide Poisoning Symptoms

Carbon monoxide poisoning will manifest itself with symptoms that occur in the parts of the body that need oxygen the most, namely the heart and central nervous system (CNS) . Initial symptoms usually include nausea, malaise, fatigue, and a dull but persistent headache .

As CO continues to accumulate in the bloodstream, the depletion of oxygen in the tissues will trigger an increasingly worse cascade of symptoms, including :

  • Dizziness
  • Difficulty breathing ( shortness of breath)
  • Chest pain
  • Threw up
  • Irregular heart rate ( arrhythmia ) or fast heartbeat ( tachycardia )
  • Shaky gait
  • Confusion
  • Decreased respiratory rate.
  • Lower your heart rate.
  • Delirium
  • Seizures
  • Unconscious

Death most often occurs as a result of respiratory arrest .

Even after a person has been treated for carbon monoxide poisoning, there is a risk of long-term and even permanent neurological complications, including memory problems, irritability, depression, speech problems, partial vision loss, dementia and symptoms similar to Parkinson's .


Carbon monoxide is easily absorbed into the body through the lungs. When CO enters the bloodstream, it predominantly binds to hemoglobin , a protein in red blood cells responsible for carrying oxygen throughout the body. In this way, CO prevents oxygen from reaching the tissues and cells that need it to survive.

Carbon monoxide is a natural by-product of combustion. In most cases, poisoning occurs as a result of inhaling the gas , as it quickly accumulates in a confined space (usually due to poor ventilation).

Common sources of CO include:

  • Wood stoves
  • House fires
  • Automobile exhaust gases
  • Gas or propane ovens and grills
  • Charcoal and hibachi grills
  • Non-vented gas, kerosene, or propane heaters
  • Gas generators
  • Gas Clothes Dryers

Riding in the back of a truck is a common cause of carbon monoxide poisoning in children. Also, stopping your vehicle for the winter can poison passengers if the tailpipe is clogged with snow. In fact, any perforation in the exhaust manifold of a car or boat can allow CO to flood the interior.

Carbon monoxide poisoning can also happen on purpose. According to a study published in the Annals of the American Thoracic Society , 831 suicides in 2014 were due to carbon monoxide poisoning caused by car exhaust or a fuel source in the home .

At the same time, the number of suicides using this method has been declining since 1975, when federal law mandated the installation of catalytic converters in all automobiles .


If carbon monoxide is not recognized as the cause of your symptoms, you may be misdiagnosed when you first go to the emergency room. Therefore, it is important to inform the ER doctor of your suspicions if you think CO is involved.

Diagnosis is relatively straightforward. It includes a non-invasive probe called a CO-oximeter that can be placed on a toe, toe, or other parts of the body. The oximeter contains two diodes that emit light beams of different wavelengths. The amount of light absorbed by the tissues can tell doctors how much carboxyhemoglobin (a compound formed by the bonding of CO and hemoglobin) is in the blood.

Under normal conditions, the level of carboxyhemoglobin is less than 5% compared to free hemoglobin. Poisoning usually occurs if the level is above 10%. Death can occur at levels above 25% .

Conventional pulse oximeters are useless because they cannot distinguish between carboxyhemoglobin and oxyhemoglobin (a compound formed by the binding of oxygen to hemoglobin).

Watch out

If carbon monoxide poisoning is suspected, the first step is to get yourself and others away from the source of carbon monoxide. Even if the symptoms are mild, you should seek emergency medical attention.

Treatment may include injection of compressed oxygen through a mask without circulation. By increasing the level of oxygen in the blood, CO can be excreted from the body four times faster than on its own . Oxygenation can actually break down carboxyhemoglobin and release hemoglobin back into the bloodstream.

In severe cases, a pressure chamber can be used that can supply 100% oxygen in a high pressure environment. Hyperbaric oxygen removes CO from the blood almost four times faster than oxygen supplied at normal atmospheric pressure. It also allows oxygen to partially bypass hemoglobin and be delivered directly to tissues.

In addition to oxygen, other treatments may be required, including:

  • Cardiac life support system for the treatment of dangerous arrhythmias
  • IV fluid to treat hypotension.
  • IV sodium bicarbonate to treat metabolic acidosis (build-up of acids in the blood due to suppression of kidney function).
  • Valium (diazepam) or dantrium (dantrolene) to treat seizures
  • Vasopressors to narrow blood vessels and stabilize suppressed heart activity


The most effective home remedy is a carbon monoxide alarm. They are available online and at most hardware stores, from $ 20 for a replacement monitor to $ 80 for a combined CO / smoke alarm.

The U.S. Consumer Product Safety Commission (CPSC) recommends that every home have at least one CO detector, preferably one for each floor.

Other recommended safety tips include:

  • Make sure your gas appliances have adequate ventilation.
  • Have a technician check your heating system, water heater, and any gas or charcoal appliances annually.
  • Never use an electric generator inside a home, garage, or within 20 feet of any window, door, or vent.
  • Check and clean the chimney annually.
  • Open the fireplace damper before lighting and after extinguishing the fire.
  • Never use a gas oven to heat your home.
  • Never leave your car in your garage.
  • Know the symptoms of carbon monoxide poisoning.

Get the word of drug information

If a carbon monoxide alarm goes off, never assume it is a false alarm, even if you have no symptoms. Since CO is tasteless and odorless, you must assume the risk is real and take the appropriate action.

First of all, don't look for a gas source. Instead, the CPSC recommends that:

  • Get outdoors immediately.
  • Call the fire department, emergency services, or 911.
  • Count to make sure it all counts.
  • Do not enter the building until rescue personnel give you permission to do so.
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