The Physiology of Oxygenation
Let’s start with what happens when you breathe in air. When oxygen enters your nose or your mouth, it then travels to your pharynx and to your throat or the larynx, then it goes into your trachea and to the bronchi. Now as we know, there are the left and the right bronchi. They branch to the bronchioles and to the alveolar sacs.
Normally, the alveolar sac is where the exchange of gases takes place—then the oxygen enters the bloodstream after being attached to a red blood cell (during the process of gas exchange inside the alveolar sac) and that’s when it’s distributed to the whole body. On the other hand, carbon dioxide or C02 is being exhaled out through the mouth or the nose.
This process in the human body is happening in normal breathing (normal respiratory rate is 12 to 20 breaths per minute). This breathing pattern is ideal for the body to release or expel carbon dioxide. However, when there is something blocking the airway or a problem in breathing, your body will not be able to process the oxygen that will be distributed to your bloodstream and you will be expelling too much carbon dioxide.
This is called tachypnea, tachy- which means fast, and -pnea which means breathing or respiration. This simply means you are exceeding 20 breaths per minute.
Experiencing tachypnea makes you expel too much carbon dioxide. What happens when we expel too much carbon dioxide? The pH in your body increases thus bringing the body into the state of alkalosis. To know more about the values of blood pH, here is a chart:
| Human Blood PH Level | |
| 6 | Acidic |
| 7 | Acidic |
| 7.35 | Acidic – Normal |
| 7.45 | Acidic – Normal |
| 7.8 | Alkaline |
| 9 | Alkaline |
In cases that the PACO2 (which is the measurement of the carbon dioxide level in the body) decreases, it would alert the other organs that you are expelling carbon dioxide too fast. Now the organs will be helping out to make sure that the body is in a homeostatic environment.
The first organs to react are the kidneys. What the kidneys would do is that they would get rid of the bicarbonate and it will cause you to urinate as normal. This will help in releasing the bicarbonate. This would help in decreasing the blood pH and will normalize the pH level.
Causes of Respiratory Alkalosis
Respiratory alkalosis occurs when the blood has a below-normal CO2 level, caused by excessive breathing.
What are the causes of respiratory alkalosis then? There is a long list of causes that we can point to. Starting with an increase in body temperature or fever, aspirin toxicity, controlled ventilation or patients that are intubated, hyperventilation, hysteria, pain, neurological injuries, embolism, and asthma.
Signs and Symptoms of Respiratory Alkalosis
Now, what signs and symptoms should nurses check?
- Increased respiratory rate
- Watch out for confusion
- Check for signs of tetany, positive Chvostek’s sign, muscle cramps, dysrhythmias
Nursing Intervention
As a nurse, what do you do for patients with respiratory alkalosis? Breathing techniques are helpful and you as the nurse should teach the patient these techniques. You can also use the paper bag breathing, or if a rebreather mask is available, that can be useful as well.
