Pulse oximetry is a method for determining the quantitative indicators of the oxygen content in human blood. This type of diagnosis refers to non-invasive research methods.
In what cases is pulse oximetry indicated?
The normal well-being of a person largely depends on how well his or her tissues and organs are supplied with oxygen. The process of saturating the blood with oxygen is called saturation. Under normal conditions, 1 g of hemoglobin binds to 1.34 ml of oxygen, resulting in arterial blood saturation from 95 to 100%, venous blood – approximately 75%. If the amount of oxygen in hemoglobin is below normal, a person feels the following signs of hypoxia – oxygen starvation:
- shortness of breath;
- short-term respiratory arrest in sleep – apnea;
- change in heart rate;
- flushing of the skin.
In addition to the state of hypoxia, pulse oximetry can be indicated for the following diseases:
- with increased blood pressure;
- with obesity;
- metabolic syndrome;
- various lung lesions;
- heart disease.
In addition to impaired functioning of a particular organ, which is caused by insufficient saturation, pulse oximetry may be necessary in the following situations:
- during surgical interventions;
- before anesthesia;
- to determine fetal oximetry during pregnancy;
- to diagnose the underdevelopment of certain organs and further maintain the vital functions of premature babies;
- to monitor respiratory failure therapy.
How is pulse oximetry performed?
The methodology for this diagnostic procedure depends on the type of study. There are two types of pulse oximetry:
- Reflected. In this case, a reflected light wave is used. For examination, an arbitrary part of the body is chosen;
- Transmission. The light wave is not reflected from organs and tissues, as indicated in the previous method, but passes through them. In this case, the device for measuring the level of oxygen is fixed on the wings of the nose, earlobe or finger.
In both cases, a special device is used, which is known as a pulse oximeter. It is a sensor that is mounted on the patient’s body and a monitor that reflects the results of the study. This device records the heart rate and percentage of oxygen saturation of arterial blood. The pulse oximetry rate for a healthy person is 95% and higher. If lower indicators are established, this indicates insufficient oxygen saturation of the blood.
To conduct pulse oximetry, you need to do some preparation:
- Before the examination, you cannot use tranquilizers and sedatives, drink coffee, alcohol and strong tea, smoke;
- The last meal should take place no later than two hours before the start of the study;
- Do not apply cosmetics to the area used for the study.
This research method is absolutely safe for health and has no contraindications.