A pulse oximeter is a medical device that measures arterial oxygen saturation. Why is this needed?
The essence of the method
Pulse oximetry measures arterial oxygen saturation, or saturation. The device takes measurements as a percentage and shows the ratio of oxygen-enriched hemoglobin to the amount of total hemoglobin in the blood. The rate of oxygen saturation determined by a pulse oximeter is 95-100%, a decrease in saturation to 93% is considered clinically insignificant.
The LEDs of the device during its operation create infrared and red light. This light passes through the soft tissues of the finger (the measurement is carried out on the terminal phalanx of one of the fingers) and is captured by a special photodetector installed opposite the light emitter. During heart contractions, oxygenated blood enters the arteries. In the intervals between heart contractions, it gives O2 to the tissues, and its content in it decreases. These fluctuations in arterial oxygen saturation can be determined using a pulse oximeter, since oxygenated and unoxygenated hemoglobin absorb light differently.
Who may need pulse oximetry
In somnology , a pulse oximeter is convenient for screening patients with suspected obstructive or central sleep apnea, chronic nocturnal hypoxemia. The accuracy of the method in these cases can reach more than 86%.
In addition, the device is used in cardiology practice to assess the severity of the condition of patients with heart failure and valvular defects, as well as in pulmonology in people with chronic obstructive pulmonary disease, bronchial asthma, pneumosclerosis, emphysema.
How to use the device
The pulse oximeter is attached to the wrist like a wristwatch, and its sensor, which determines the saturation of the blood with oxygen, is installed in the area of \u200b\u200bthe pad of one of the fingers. To fix the sensor, a plastic tip is used that visually resembles a thimble or a clothespin, and there is a short cord to connect the sensor to the main unit located on the wrist. The portable device weighs only a few tens of grams, it is easy to use (it can be installed and started by the patient himself), and does not interfere with sleep in any position.
Pulse oximetry can be done at home or in a hospital. The device contains a computer program, thanks to which the data from the pulse oximeter, when connected to a computer, are automatically downloaded there and processed. The device is simple and easy to use.
When You Can Use a Pulse Oximeter
In the diagnosis of sleep disorders, the “gold standard” is polysomnography , in which several physiological parameters are recorded throughout the entire sleep time. The study is carried out in a hospital setting.
An alternative to polysomnography is respiratory monitoring, and in cases where severe sleep apnea needs to be diagnosed, a pulse oximeter can be used. The latter research method is less accurate, it often does not determine the early stages of the disease. However, it is quite informative if carried out in accordance with the instructions for use and in accordance with the indications.
An optimal polysomnographic examination for diagnosis has two problems. The first one is the cost of the equipment. It is simply impossible to perform such a study in most Russian cities – many clinics do not have the necessary technical equipment. The cost of a pulse oximeter is relatively low – portable devices have a price of 2.5-35 thousand rubles. The second problem is that polysomnography is quite difficult for children under 7 years of age (small patients do not follow the doctor’s instructions, they sleep restlessly), while a pulse oximeter can be worn on the child’s hand during sleep.
Pulse oximeter for newborns
Pulse oximetry is widely used to determine blood oxygen saturation in newborns. For the study, special sensors for babies are used, for example, the Nonin brand .
The pulse oximeter sensor is attached to the child’s hand or foot with soft clips that protect the baby’s delicate skin from damage.
A neonatal pulse oximeter is used to monitor vital signs in newborns, including premature babies. In 76% of cases, this method of examination makes it possible to suspect malformations of the heart immediately after birth. Currently, pulse oximetry screening methods have no equal in terms of simplicity and effectiveness of diagnosing heart pathology in infants.
The device for newborns has an alarm sensor so that in the event of a significant decrease in the level of oxygen in the blood, notify the medical staff about this.
Pulse oximeter in children
Pulse oximetry in preschool children often becomes the only possible way to accurately diagnose the syndrome of obstructive or central sleep apnea, chronic nocturnal hypoxemia.
Parents can put the portable pulse oximeter provided to them at the clinic on their child’s arm during sleep. The device is gently attached to the wrist and finger, turns on and off automatically, works silently. After the blood counts are recorded, the device is returned to the medical staff, who analyze the received data to establish a diagnosis.
If you suffer from chronic lung disease, have been diagnosed with heart failure, or suspect sleep apnea, pulse oximetry may be the first step in diagnosing these conditions. By contacting the Center for Sleep Medicine at the Rehabilitation Clinic in Khamovniki, you can get advice from a sleep specialist and assistance in choosing a portable pulse oximeter, if necessary. If you need to undergo treatment to improve your sleep, it will be carried out by the department’s somnologists in the best traditions of Kremlin medicine.