Is your blood carbon dioxide (CO2) level high? Let's talk about hypercapnia!

Do you sometimes just feel tired? Or do you feel a little short of breath, or do you get a headache? Although these are normal things, sometimes there can be another reason behind this. That is, the amount of carbon dioxide (CO2) in your blood is too high. In medicine, we call this condition hypercapnia , and sometimes hypercarbia . So, let's talk about this in detail and simply today.

What exactly is hypercapnia?

Simply put, hypercapnia is when the amount of carbon dioxide (CO2) in your blood is higher than the recommended level. Now, look, this carbon dioxide (CO2) is produced as a byproduct when our body's cells produce energy. Our red blood cells then collect this CO2 and carry it to the lungs, from where it is exhaled when we exhale. So, if for some reason our body is unable to properly expel this waste product called carbon dioxide, it starts to accumulate in the blood. That's what hypercapnia is called.

This condition can be chronic , with symptoms such as shortness of breath (dyspnea) and daytime fatigue. Sometimes it can be acute, with symptoms that are more severe.

Important: Acute hypercapnia is a medical emergency. It can affect the brain (neurological symptoms) and cause confusion, disorientation, and paranoia.

What is the difference between Hypercapnia and Hypoxemia?

These two can be a bit confusing. Hypercapnia is an increase in carbon dioxide (CO2) in the blood. Hypoxemia is a decrease in the amount of oxygen in the blood. Sometimes both of these conditions can occur at the same time. That means there can be an increase in CO2 in the blood and a decrease in oxygen.

What are the symptoms of Hypercapnia?

There are several symptoms that can occur in a state of hypercapnia. These can vary depending on the nature of the condition (whether it is chronic or acute).

• Shortness of breath: It can feel like you can't breathe, like your chest is constricting.
• Headaches: A headache that occurs frequently, sometimes worse in the morning.
• Persistent tiredness or sluggishness during the day: A feeling of being tired no matter how much sleep you get.
• Disorientation: Loss of clear understanding of things like location and time.
• Confusion or altered mental state: Changes in thinking and decision-making.
• Paranoia: An irrational fear that others will harm you.
• Depression: A state of feeling unhappy and hopeless.
• Seizures: In some severe cases, seizure-like conditions may occur.

Chronic hypercapnia may initially present with mild symptoms such as fatigue, headache, and shortness of breath. However, over time, these can progress to brain-related symptoms such as confusion. Acute hypercapnia can cause sudden onset of brain-related symptoms, headache, and shortness of breath.

What are the causes of hypercapnia?

Hypercapnia can be caused by any condition that increases the level of carbon dioxide (CO2) in the body, or prevents CO2 from entering the lungs and leaving the body. Two main factors that contribute to this are hypoventilation and V/Q mismatch .

• Hypoventilation: This means that your breathing rate is too slow, or you breathe too shallowly. This means that you are unable to properly exhale the amount of CO2 that is produced in your body.
• V/Q mismatch: This is a bit complicated. Simply put, "V" stands for Ventilation, which is the amount of air entering the lungs. "Q" stands for Perfusion, which is the amount of blood flowing into the lungs. So, if the lungs are getting enough air but not enough blood flow, or if the blood flow is good but not enough air is flowing, this V/Q ratio becomes unbalanced. In some lung diseases, there is a "dead space" in the alveoli of the lungs, where blood is not getting enough blood. Then, even though the lungs are filled with air, not all of the CO2 can be removed from the blood.

COPD (Chronic Obstructive Pulmonary Disease) and sleep apnea are the two most common causes of hypercapnia. There are also other causes:

• Conditions that weaken the system that controls your breathing: Examples include a stroke, excessive use of sedatives, obesity hypoventilation syndrome, and hypothyroidism.
• Conditions that affect your spine, nerves, or muscle control: Examples include multiple sclerosis (MS), nerve or spinal cord disorders, amyotrophic lateral sclerosis (ALS), and muscular dystrophy.
• Changes in the structure of the chest or spine: Examples include flail chest (fracture of the chest wall) and ankylosing spondylitis (inflammation of the joints of the spine).
• Poisonings: Examples include tetanus and botulism.
• Pulmonary embolism.
• Vascular disease.

Fever and exercise can also cause CO2 levels to increase. However, most people's bodies adjust to this and return to balance. Sometimes, hypercapnia can occur even when a person with COPD is given oxygen.

What are the risk factors for this condition?

People with heart disease, lung disease, muscle disease, and diseases of the nervous system (brain and spinal cord) are at higher risk of developing hypercapnia. Also, if you take medications that make you sleepy (e.g., opioids, benzodiazepines), you may be at higher risk of developing hypercapnia because your breathing may be shallow or slow.

What are the complications that can occur due to hypercapnia?

If your body cannot control these high carbon dioxide levels, life-threatening conditions can occur. These include:

• Respiratory acidosis: This is when the pH of your blood drops below normal levels, making it too acidic.
• Respiratory failure: This is when your body's tissues are unable to get enough oxygen.
• Cardiac arrest.
• Coma.

How is Hypercarbia diagnosed?

To diagnose hypercapnia, doctors will do special blood tests that measure the amount of carbon dioxide in your blood. They may also do other tests to check for other conditions that could be causing hypercapnia.

What tests can be used?

Tests such as these may be done to diagnose hypercapnia or underlying conditions that cause it:

• Pulse oximetry: This uses a small sensor placed on your finger to measure the amount of oxygen in your blood. This is a painless, routine test. It can give your doctor a quick idea of ​​your condition.
• Arterial blood gas test (ABG): This measures the level of carbon dioxide in your blood by taking a blood sample from your wrist, arm, or groin using a needle.
• Blood tests: Various blood tests may be done to detect hypercapnia or its causes. Examples include a complete blood count (CBC), toxicology screen, CO2 blood test, and thyroid function tests.
• Imaging: The doctor may order chest X-rays or CT scans of the chest/head to try to identify underlying medical conditions.
• Pulmonary function tests (PFTs): These tests can be done to see how well your lungs are working to identify underlying medical conditions.

How is hypercarbia treated?

Treatment for hypercapnia depends on the cause. Doctors may use the following treatments:

• Non-invasive ventilation (NIV): This involves using a machine to help you breathe through a mask that fits over your face. For example, CPAP (Continuous Positive Airway Pressure) or BiPAP (Bilevel Positive Airway Pressure) (often called BiPAP®) machines.
• Oxygen therapy.
• Medications to reverse overdose: If hypercapnia is caused by an overdose of drugs that cause drowsiness (e.g. opioids), your doctor may prescribe certain medications that can reverse the effects of those drugs.
• Mechanical ventilation: In some severe cases, the patient may need to be connected to a breathing machine.

Are there any side effects of the treatment?

Giving oxygen to someone with COPD can sometimes make hypercapnia worse. This can increase the V/Q mismatch, or your red blood cells can release CO2 into the blood (the Haldane effect), but the body can't get rid of that CO2 properly.

Can Hypercapnia be prevented?

The best way to prevent hypercapnia is to take all your prescribed medications exactly as prescribed and to manage any underlying medical conditions. If you have COPD, talk to your doctor about how to manage flare-ups.

What is the outlook for hypercarbia?

The outlook for hypercapnia depends on the cause. Many causes, if identified early, can be treated. Long-term hypercapnia caused by sleep apnea can be prevented by using a device prescribed by a doctor or by some types of surgery.

Some studies show that among people with COPD, those with hypercapnia may have a slightly worse prognosis than those without hypercapnia.

How do I take care of myself?

The best way to take care of yourself is to manage any underlying conditions that put you at risk for hypercapnia. If you have COPD, sleep apnea, or any other condition that puts you at risk for hypercapnia, talk to your doctor about what symptoms to watch for.

When should I see a doctor?

If you have symptoms of hypercapnia, especially if you have other medical conditions that put you at risk, talk to your doctor.

When should I go to an Emergency Treatment Unit (ETU) ?

If you have any of these serious symptoms, go to the nearest emergency room immediately:

• Seizures.
• Altered mental state or confusion.
• Disorientation.
• Mental confusion (Paranoia).
• Blue skin, nails or lips.

What questions should I ask my doctor?

It may be helpful to ask your doctor questions like these:

• Why did this happen to me?
• How can this be prevented in the future?
• What treatment options do I have?

Our bodies are constantly trying to maintain balance without us even thinking about it. Oxygen and carbon dioxide levels can fluctuate, but our bodies adapt to it. However, some medical conditions make it difficult for our bodies to maintain the balance they need. That's when conditions like hypercapnia occur.

The excess carbon dioxide that occurs during hypercapnia can cause life-threatening complications. If you have a medical condition that puts you at risk for hypercapnia, make a plan with your doctor about what to do if you develop any worrisome symptoms. See a doctor right away if you have symptoms of hypercapnia. Go to the emergency room if you have mental changes such as confusion, seizures, or confusion.

Summary (Take-Home Message)

Dear friends, I hope you now have a good understanding of what hypercapnia is, its causes, symptoms, and treatments. Remember, an increase in the amount of carbon dioxide (CO2) in your blood is not something to be taken lightly.

• If you have symptoms like frequent fatigue, shortness of breath, or persistent headaches , talk to a doctor about it.
• If you have lung diseases like COPD or sleep apnea , be especially careful about hypercapnia.
• If you experience symptoms such as sudden loss of consciousness, confusion, or seizures , it is a medical emergency. Go to the hospital immediately.
• It is very important to follow medical advice and take the prescribed medications correctly.

May we all have the strength to live a healthy life!

` Hypercapnia, Carbon Dioxide, Breathing Difficulty, COPD, Sleep Apnea, Blood Gas Testing, Respiratory Disease