Today the pulsoksimetriya, no doubt, is the most widespread type of tool monitoring of function of external respiration. Gradually this method removed from the field of anesthesiology resuscitation and to other spheres of medicine, for example, in pulmonology, therapy and the general medical practice. Simplicity of performance of a research, a possibility of continuous monitoring for a long time, not invasiveness of a method made it very popular among as the practicing doctors, and among patients.
In parallel there is an improvement and distribution of monitors for a pulsoksimetriya. Now the pulsoksimetriya can be carried out not only by means of the stationary monitor having the corresponding function but also by means of portable pulsoksimetr and also by means of a special option in the smartphone.
We will try to understand this article as the quality of a pulsoksimetr influences the accuracy of measurement of indicators of a saturation of hemoglobin by it and whether it is possible to trust indications of portable devices and smartphones.
In general, there are several main characteristics of any monitor which need to be learned before passing to thorough investigation of model. They include:
Reliability and durability. Monitor service life from the first inclusion before the first breakage at some models makes how many days, and at others can exceed 10–15 years. In relation to pulsoksimetra it means that the Chinese portable device will serve to you, most likely, much less, than the good monitor from the proved company.
Accuracy of measurement of parameters. Compliance to the characteristics given in the passport is guaranteed, as a rule, only by solid manufacturing firms. It is clear, that oxygen the producer of the smartphone or the software for it (even if it paid) will not give any guarantees of high-quality measurement of indicators of saturation of hemoglobin of an arterial blood to you.
Ability it is correct to work under trying conditions (a bad peripheral blood stream, abundance of a phlegm in respiratory tracts, high frequency of ventilation, vibration, temperature drops and atmospheric pressure and so on). Here simple pulsoksimetra, as a rule, lose at once to stationary models. The more simply (cheaper) the device, the less it will be useful to you in the specified conditions.
Ergonomics of model, and correctly organized interface of the user is of particular importance.
Availability and cost of expendables and accessories. Costs of maintenance of the monitor in working order for several years can sometimes exceed its cost.
Service guarantees. It is clear, that portable pulsoksimetr from the Chinese producers bought on the websites like Aliexpress, will have no guarantee maintenance.
One more one moment distinguishing qualitative pulsoksimetr from low-quality is existence of various types of sensors. It matters in two aspects: when using a pulsoksimetr at patients of various age groups and at measurement of indicators at patients with disturbances of peripheric circulation. Information on decrease or increase in SaO2 anyway is reflected in the display with some delay and in some cases it makes several tens of seconds. Speed of response of a pulsoksimetr is defined on changes of SpO2 by the linear speed of an arterial blood-groove which, in turn, depends on warm emission and a gleam of vessels. Normal blood of the next stroke output reaches the manual sensor in 3–5 seconds, and ear — in 2–3 seconds after warm reduction. At the expressed peripheral vasoconstriction or a hypokinetic condition of blood circulation this interval can increase. Therefore at heavy patients with disturbances of a peripheral blood-groove use of the ear sensor what many simple pulsoksimetra are not able to afford is much more preferable.
Moreover, many simple inexpensive models of pulsoksimetr have no possibility of display of the photoplethysmogram on the monitor at all. This fact calls into question reliability of results of a pulsoksimetriya in general as well-known that assessment of indicators of saturation of hemoglobin of an arterial blood oxygen can be made only after on the monitor the correct curve of the photoplethysmogram begins to be displayed.
Thus, it is possible to draw a conclusion that the quality of the diagnostic information provided pulsoksimetry is in direct dependence on quality of the monitor which is used for carrying out measurement.