Language
Country/Area
No result found
The secret journey of oxygen: How does a pulse oximeter identify oxygenated and non-oxygenated hemoglobin?
The pulse oximeter, an indispensable tool in modern medicine, is designed to assess the oxygen saturation in human blood. As a non-invasive method, it uses optical technology to measure the ratio of oxygenated hemoglobin to non-oxygenated hemoglobin in tissues. Through this process, medical personnel can quickly understand the patient's oxygen status and make important judgments about their health.
Pulse oximeters use a dual-wavelength light beam to pass through tissue and determine the oxygen level in the blood by comparing the difference in absorption between oxygenated and non-oxygenated hemoglobin.
The core working principle of the pulse oximeter is to emit red light (660 nm) and infrared light (940 nm) through a light-emitting diode (LED) on one side and transmit it through the patient's fingertips or earlobes. Part. Oxygenated hemoglobin absorbs more infrared light, while unoxygenated hemoglobin absorbs more red light. In this way, by measuring the changes in the amount of light transmitted to the photodetector, the pulse oximeter can infer the proportion of oxygenated hemoglobin and thus calculate the oxygen saturation (SpO2) of the blood.
This process can monitor the patient's blood oxygen level in real time without harming the patient, which is particularly important during emergency treatment, surgery and anesthesia. For patients suffering from hypoxia, the pulse oximeter can send out timely alarms to help medical staff take necessary intervention measures.
Clinical Applications
Pulse oximeters have a wide range of clinical uses, including in intensive care and emergency departments. Pulse oximeters allow doctors to not only assess oxygenation but also monitor other vital signs, such as pulse rate. Furthermore, with the advent of portable pulse oximeters, both healthcare workers and patients can perform self-monitoring in non-medical settings.
With the development of the COVID-19 epidemic, the demand for pulse oximeters has increased rapidly and has become a part of home medical care, helping to detect asymptomatic hypoxia patients at an early stage.
However, pulse oximeter can only provide information on oxygenation status, and the assessment of oxygen metabolism capacity needs to be combined with other detection methods. For example, monitoring a patient's carbon dioxide levels can help determine how well they are using oxygen. Patients with some respiratory diseases such as chronic obstructive pulmonary disease (COPD) also need to be considered comprehensively, as pulse oximeters may give misinterpretations in such cases.
Advantages and limitations
The use of a pulse oximeter has many advantages. Among them, its non-invasive, immediate and easy-to-operate characteristics make it widely used in clinical practice. However, it is important to note that pulse oximeter systems may be less accurate under certain conditions, such as when blood flow is poor or if the patient has darker skin. Studies have shown that these conditions can lead to skewed measurements, especially when oxygenation levels are low.
In reality, pulse oximeters are designed based on healthy populations and therefore have limited accuracy in clinically unstable patients.
In addition, pulse oximeters still cannot provide a comprehensive analysis of respiratory function, and they do not reflect carbon dioxide levels or acid-base status in the blood. In cases of major health problems, such as carbon monoxide poisoning, pulse oximeters can give falsely high readings, misleading healthcare workers.
ConclusionAs an important medical device, pulse oximeter has indeed made important contributions in detection and monitoring. Understanding its principles, advantages and limitations plays an important role in improving the quality of medical services. More importantly, with the advancement of technology in the future, it is expected to overcome the current limitations and achieve wider applications, whether in homes, medical units or other places. Such progress will not only affect professional medical workers, but also the safety and health of every patient. With the advancement of technology, what changes will medical testing usher in in the future?
