What is Hyperbaric Treatment of Carbon Monoxide Toxicity?
Carbon monoxide (CO) is a harmful gas that is produced when carbon-based materials don’t completely burn off. Usual sources include engines, non-electric heaters, furnaces, and smoke from fires. You can also get poisoned by inhaling or touching methylene chloride (commonly used in paint removers), which turns into CO within your body. Carbon monoxide can attach itself to the hemoglobin in your red blood cells — that is, the things that carry oxygen around your body — more easily than oxygen can. This process forms a substance called carboxyhemoglobin, which blocks oxygen from being transported around the body, leading to a lack of oxygen, especially in the brain and heart.
Carbon monoxide can also attach to certain proteins in your cells, leading to problems with cellular respiration, which is how cells “breathe”. Another danger associated with carbon monoxide poisoning is that it can trigger inflammation in the brain, leading to nerve cell damage. This is known as delayed neurologic sequelae, and it can result in severe neurological problems over time.
What Causes Hyperbaric Treatment of Carbon Monoxide Toxicity?
Carbon monoxide (CO) is a type of gas that you cannot see, smell, or taste. This makes it particularly dangerous in areas that have poor airflow because people can breathe in high levels of it without realizing. This can cause them to lose consciousness and, in severe cases, die. Carbon monoxide poisoning might happen on purpose, accidentally, or for reasons we don’t know.
If someone is poisoned, it’s important to consider the possibility that they might have done it to themselves until we know more about what happened. Accidental poisonings can occur more often in certain times or situations. For example, they are common during winter, cold spells, or after natural disasters when there’s no electricity. During these times, people might run devices like generators or heaters in enclosed spaces, leading to higher levels of carbon monoxide.
Faulty kitchen stoves, charcoal grills, or indoor furnaces and heaters that are not ventilated correctly or defective can also cause carbon monoxide poisoning. It’s not uncommon for groups of people, like families or coworkers, to show signs typical of carbon monoxide poisoning all at the same time if they are in the same place where the gas is being released.
Risk Factors and Frequency for Hyperbaric Treatment of Carbon Monoxide Toxicity
CO (carbon monoxide) poisoning is a major health concern. In the United States, it results in about 40,000 emergency room visits and approximately 6,000 deaths annually. While the majority of these cases are intentional, around 500 of these deaths are accidental, primarily due to smoke inhalation. The most frequent causes of unintentional CO poisoning include running combustion engines in enclosed spaces, faulty propane or natural gas heaters, and house fires.
Workplace conditions such as using paint strippers containing methylene chloride in poorly ventilated spaces, without gloves or protective respirators, pose a risk for unintentional CO poisoning too. This is because methylene chloride can turn into CO in the liver. CO poisoning poses an increased risk to children and the elderly with other health issues, particularly heart, neurological and lung diseases. Such individuals have a lower capacity to withstand exposure to CO.
- CO poisoning results in about 40,000 emergency department visits annually in the United States.
- It leads to approximately 6000 deaths, with around 500 of them being accidental.
- Most unintended CO poisonings are caused by smoke inhalation.
- Common sources of unintentional CO poisoning are running combustion engines in enclosed spaces, faulty heaters and house fires.
- Using paint strippers with methylene chloride in poorly ventilated areas without proper protection can cause CO poisoning.
- Children and elderly individuals with heart, neurological, or lung diseases are at a higher risk of CO poisoning because they are less capable of handling CO exposure.
Signs and Symptoms of Hyperbaric Treatment of Carbon Monoxide Toxicity
Carbon monoxide (CO) poisoning can be hard to diagnose because its initial symptoms are quite common and can often be confused with other conditions, particularly in cold weather when viral gastroenteritis infections are common. Therefore, it’s important to be highly alert to avoid missing this dangerous condition.
Typically, people suffering from CO poisoning may feel unwell, experience nausea, throw up, feel dizzy, and have headaches. In more serious cases, they might show signs of confused thinking, lose consciousness, have seizures, or even fall into a coma. Sometimes, the presence of “cherry red” lips and skin is linked with CO poisoning, but this is not a reliable symptom and often does not appear.
CO poisoning can also lead to heart-related issues such as chest pain, lack of blood flow to the heart, irregular heartbeat, acute heart failure, and often severe lactic acidosis. Any situation involving smoke inhalation or unexplained loss of consciousness or coma should be evaluated for possible CO poisoning. A mini-mental exam could be used to check cognitive function if the patient is awake. One clear sign of CO poisoning is difficulty with rapid alternating movements, which is a quick way to check for brain function impairment.
- Feeling unwell
- Nausea
- Vomiting
- Dizziness
- Headaches
- Confused thinking (in severe cases)
- Loss of consciousness (in severe cases)
- Seizures (in severe cases)
- Coma (in severe cases)
Testing for Hyperbaric Treatment of Carbon Monoxide Toxicity
CO-oximetry is a test that uses special light to measure the levels of oxygen-carrying hemoglobin and carbon monoxide in your blood. Some devices can even measure a form of hemoglobin called methemoglobin. During this test, it’s important that nothing interferes with the device’s light, such as nail polish or other types of light, as they could lead to incorrect results.
If a person is suspected to have been exposed to carbon monoxide, blood should be drawn for testing as soon as possible. Depending on the results and the person’s symptoms, the following levels of carbon monoxide in the blood can guide treatment:
- 0-5% is normal for most people.
- 5-10% can be normal for a smoker.
- Over 10% is usually abnormal and would typically require treatment with oxygen.
- Over 15% is significantly abnormal and requires immediate treatment.
It’s important to note that CO-oximetry alone should not be the only test used to diagnose carbon monoxide poisoning. It has not been fully validated in clinical trials. Other tests such as a blood count, metabolic panel, lactic acid levels, and blood gas levels can also be very informative.
When evaluating someone for carbon monoxide poisoning, other factors should also be considered. These can include alcohol intoxication, cyanide poisoning, inhalation of smoke (especially from burning plastics), and drug use. Unconscious patients should have their blood sugar levels monitored closely. Cardiac toxicity tests may be done and a chest x-ray could be helpful to check for fluid in the lungs, especially if the person has inhaled smoke.
In cases of suspected suicide attempts, tests for salicylate and acetaminophen levels are commonly performed. A CT scan of the brain is generally not helpful unless other causes of headache and neurological impairment need to be ruled out, such as bleeding in the brain. It’s worth noting that carbon monoxide poisoning has been linked to bleeding in an area of the brain known as the globus pallidus and sometimes in white matter, but these are rare occurrences.
Treatment Options for Hyperbaric Treatment of Carbon Monoxide Toxicity
If you’re suspected or confirmed to have carbon monoxide (CO) poisoning, one of the first treatments would be to receive a high supply of oxygen through a mask. It’s also crucial to remove you from the source of the CO. In severe cases where the patient can’t protect their airway (the path from the nose and mouth to the lungs), doctors will insert a tube into the windpipe to help with breathing. This tube (also known as intubation) provides 100% oxygen.
While undergoing treatment, it’s important you’re closely monitored for heart irregularities. The treatment of any accompanying conditions can also play a big role in improving your health outcomes. For instance, if you’re suspected of also having cyanide poisoning due to smoke inhalation, you would be treated with a special kit designed to counteract the poison.
Determining whether the CO poisoning was accidental or intentional is critical. If it’s unclear, doctors err on the side of caution and treat it as a potential suicide attempt. If you’re able to talk, the medical team may assess whether you’re experiencing suicidal thoughts. This information is crucial in planning your ongoing care after the crisis has been addressed.
The use of hyperbaric oxygen therapy (HBO2), which is a treatment involving breathing in pure oxygen in a pressurized room or tube, can be a controversial decision. However, most experts agree that it should be used if there’s loss of consciousness, new neurologic deficits or mental status changes, issues with blood circulation in organs, or if you’re pregnant and have certain levels of CO in your blood.
When deciding on the treatment, the level of CO in your blood is not the only factor considered, as it doesn’t always align with the severity of your symptoms. If the CO level is above a certain point, it’s generally considered severe poisoning, and most experts agree treatment is necessary. It’s often better to be safe and use HBO2 as it can be hard to predict who will develop delayed neuropsychiatric syndrome (DNS). DNS can occur about 20 days after poisoning and can cause cognitive problems, personality changes, movement disorders, and specific neurological issues which typically disappear after a year but may become permanent. HBO2 helps reduce the risk of DNS by aiding in the recovery of the brain after injury.
HBO2 works by not only quickly displacing the CO from the blood’s oxygen-carrying cells but also increasing the amount of oxygen delivered to tissues. It also minimizes the collection of specific cells on the damaged lining of blood vessels in the brain, reducing swelling and decrease cell damage. The extra oxygen helps to decrease the CO bound in the cells and restore cell functioning, especially important for neurons.
The number of HBO2 treatments needed and their duration can vary. The common aim is to provide 100% oxygen under high pressure (two to three atmospheres) for about 60 to 90 minutes. This clears the carbon monoxide faster and helps with the brain’s recovery. For severe cases of CO poisoning, it’s typically recommended to have two to three treatments per day. Moderately severe cases may only need one treatment. HBO2 is most beneficial when applied within the first six hours of being exposed to CO.
Once you’ve received the necessary medical treatment, your next steps will depend on your individual circumstances. If your poisoning was unintentional, you may return home, with instructions to return to the hospital if any neurological issues arise. You might also have a check-up with your primary care physician to perform neurological testing if problems persist or reoccur. If the poisoning was a suicide attempt, you would typically be referred for ongoing psychiatric care, potentially remaining in the hospital under monitored care.
What else can Hyperbaric Treatment of Carbon Monoxide Toxicity be?
- Diabetic ketoacidosis
- Encephalitis
- Meningitis
- Migraine
- Opioid overdose
- Hypoglycemia
Possible Complications When Diagnosed with Hyperbaric Treatment of Carbon Monoxide Toxicity
- Memory loss
- Loss of sight due to brain damage (cortical blindness)
- Problems in thinking and memory (dementia)
- Feeling persistently sad or down (depression)
- Difficulty walking (gait problems)
- Forgetfulness (memory loss)
- Mental health issue causing trouble with reality (psychosis)
- Difficulty speaking (speech problems)
Recovery from Hyperbaric Treatment of Carbon Monoxide Toxicity
If a patient is thought to have purposely ingested poison, it’s important for them to see a mental health professional, such as a psychiatrist.
