High level of carbon dioxide in blood

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Hypercapnia, or a high level of carbon dioxide in the blood, is a serious medical condition that can result in permanent damage to internal organs or result in death if not treated appropriately and immediately.

Medications, medical conditions or environmental factors can contribute to high carbon dioxide levels in the blood. Carbon dioxide poisoning has a number of symptoms in common with carbon monoxide poisoning, but they are not the same condition.


Carbon dioxide produced by the human body is not a toxin. Carbon dioxide levels in the blood are not dangerous until they reach high levels. This gaseous metabolic byproduct typically exits the body quickly. Once it dissolves into the blood stream, it becomes bicarbonate and is flushed out by the kidneys or carried to the lungs, transformed back into carbon dioxide and exhaled. The same elimination process expels inhaled carbon dioxide.


The most common cause of a high carbon dioxide level in the blood is high bicarbonate levels due to the use of medications. Taking diuretics, the prolonged steroid use or the abuse of laxatives all cause high levels of bicarbonate in the bloodstream.

Chronic Obstructive Pulmonary Disease (COPD) increases carbon dioxide levels due to reduced oxygen efficiency. Re-breathing expelled carbon dioxide due to inadequate ventilation results in carbon dioxide poisoning as well. Scuba divers who practice skip breathing---holding the breath in order to save the air tank's oxygen---experience hypercapnia frequently.


Mild symptoms of high levels of carbon dioxide in the blood include flushed skin, muscle twitches, elevated heart rate, shortness of breath and minor mental impairment such as confusion. Moderate symptoms of hypercapnia include lethargy, panic, dizziness and excessive sweating. Severe symptoms of carbon dioxide poisoning include unconsciousness, seizures, coma, respiratory arrest and death. The longer the individual goes without treatment, or the longer the exposure is to an external carbon dioxide source, the more severe her symptoms become and the faster her medical condition deteriorates.


A high level of carbon dioxide in the blood may result in permanent damage to the brain or heart when not treated immediately. Depending on the severity of the carbon dioxide poisoning, the individual receives oxygen through an oxygen mask, a ventilator or hyperbaric chamber. Hyperbaric chambers pressurise oxygen to twice its normal pressure and force oxygen into the body. This process hastens the removal of carbon dioxide from the bloodstream.


Carbon dioxide and carbon monoxide are often confused with each other. Both are gases without colour, taste or odour. Both are poisonous at high levels and can kill. However, they have different chemical compositions and origins. Carbon dioxide is one carbon molecule to every two oxygen molecules. Carbon dioxide is a natural gaseous byproduct resulting from the respiration of an organism or its metabolic function. Carbon monoxide is one carbon molecule to every oxygen molecule. Carbon monoxide is the result of the inadequate and incomplete burning of a carbon-based fuel.


Ensuring adequate ventilation of enclosed spaces, refraining from skip breathing and properly using steroids and laxatives are a few ways to prevent high carbon dioxide levels in blood. Individuals with medical conditions such as COPD and those taking medications, such as diuretics or prescription steroids, can avoid hypercapnia by maintaining regular blood-testing schedules.