Practical Application of Pulse Oximetry

Practical Application of Pulse Oximetry

Practical Application of Pulse Oximetry

Practical Application of Pulse Oximetry


Practical application of pulse oximetry In order for the pulse oximeter to work correctly, it is recommended to adhere to the following rules:

  • The pulse oximeter must be kept permanently connected to the electrical network to charge the batteries;
  • Turn on the pulse oximeter and wait for it to perform a self-test;
  • Select the required sensor, suitable in size and for the selected installation conditions ;
  • Place the sensor on the selected finger, avoiding excessive pressure;
  • Wait a few seconds for the pulse oximeter to determine the pulse and calculate the saturation;
  • Look at the pulse wave curve (without this, any values ​​will not be reliable);
  • Look at the displayed heart rate and saturation numbers. Be careful about evaluating them when their values change quickly (for example, 99% suddenly changes to 85%). This is physiologically impossible;
  • When in doubt, evaluate the patient clinically rather than relying on a machine.

Practical Application of Pulse Oximetry Warnings:

  • The patient may experience discomfort or soreness with continuous use of the device, especially in patients with a microcirculatory barrier.
  • Recommended to wear the sensor on the same finger for no more than 2 hours in a row.
  • Individual patients need to be examined more closely during placement sensor. The device should not be placed on edematous and thin tissues.
  • The light (infrared is invisible to the eyes) emitted by the device is harmful to the eyes, therefore the user and service technician must not look directly into the light.
  • The fingernail of the patient being examined should not be covered with varnish or other cosmetics.
  •  The target’s nail should not be too long.
  • Please refer to relevant literature for clinical limitations and measures precautions.

Possible algorithm of Pulse Oximetry. Possible alarms, algorithm of actions for Pulse Oximetry:


  • “Low oxygen saturation” (it will be necessary to check the patient’s consciousness, airway patency. If necessary, you will need to give oxygen or call for help);
  • “No pulse is detected”(it is recommended to check the pulse waveform on the display of a pulse oximeter, or to feel the pulse on the central artery. If it is absent, cardiopulmonary resuscitation will be required).

On most pulse oximeters, you can change the oxygen saturation and pulse rate alarm limits as desired.

However, do not change them to silence the alarm. This can lead to a life-threatening situation for the patient.

Practical Application of Pulse Oximetry

Practical Application of Safety instructions of Pulse Oximeter


  • Check your pulse oximeter and accessories periodically to make sure there are no visible damage that could affect the safety and monitoring of the patient through cables and converters.
  • It is recommended that the device is checked at least once a week. With the obvious damage, stop using the device.
  • In addition, a general check of the pulse oximeter including safety checks such as leakage current should only be performed by qualified personnel once every 12 months.
  • Required maintenance should only be carried out by qualified service engineers. Users are not allowed to do this on their own.
  •  The pulse oximeter must not be used in conjunction with devices not specified in this manual. Only accessories specified or recommended by the manufacturer can be used with this device.
  • The pulse oximeter was calibrated before it was discontinued, recalibration is not required.

 Attention! Main Warnings

  1.  DO NOT use the pulse oximeter in an environment with flammable gases such as some flammable anesthetics.
  2. Make sure that the environment in which the pulse oximeter is operated is not exposed to any sources of strong electromagnetic interference such as radio transmitters, mobile phones, etc.
  3. Keep them away from the product. High quality electromagnetic radiation emitted by such devices can significantly affect the performance of the pulse oximeter.
  4.  DO NOT use a pulse oximeter during an MRI or CT scan.
  5. Be careful when using the lanyard. Improper use of the cord may cause damage to the device, which is not covered by the manufacturer’s warranty.
  6. Rocking the device with the cord will void the warranty. Please do not use a cord if you have allergic to its material…
  7. Keep the pulse oximeter away from dust, vibration, corrosive substances, explosives, high temperature and humidity.
  8.  If the pulse oximeter gets wet, please stop using it.
  9. When the pulse oximeter is transferred from a cold environment to a warm or humid environment, please do not
    use it immediately.
  10. DO NOT use sharp objects to press the keys on the front panel.

Practical Application of Pulse Oximetry

Other practical application of Pulse Oximeter:


  • To assess the viability of limbs after plastic and orthopedic operations, vascular prosthetics. Pulse oximetry requires a pulsating signal, and thus helps to determine if the limb is receiving blood;
  • Helps to reduce the frequency of blood sampling for gas analysis in patients in the intensive care unit, especially in pediatric practice;
  • The ability to limit the likelihood of developing damage to the lungs and retina with oxygen in premature infants. Although pulse oximeters are calibrated for adult hemoglobin (HbA), the absorption spectra of HbA and HbF are identical in most cases, making the technique equally reliable in infants;
  • During thoracic anesthesia, when one of the lungs collapses, helps to determine the effectiveness of oxygenation in the remaining lung;
  • Fetal oximetry is an evolving technique. Reflected oximetry, 735 nm and 900 nm LEDs are used. The probe is placed over the temple or cheek of the fetus. The sensor must be sterilized. It is difficult to fix, the data are not stable for physiological and technical reasons.

Other difficulties when using such a monitor:

  • Abnormal hemoglobin types can give saturation values ​​as high as 85%;
  • Carboxyhemoglobin, which appears during carbon monoxide poisoning, can give a saturation value of about 100% (the pulse oximeter gives false values ​​for this pathology)
  • Some dyes, including nail polish, can cause an underestimated saturation value (this must be taken into account when choosing a sensor model);
  • Vasoconstriction, hypothermia weaken tissue perfusion and impair signal registration;
    tricuspid regurgitation causes venous pulsation and a pulse oximeter can record venous oxygen saturation;
  • Violation of the heart rhythm can interfere with the perception of the pulse signal by the pulse oximeter;
    lagging monitor. This means that the partial pressure of oxygen in the blood can decrease much faster than the oxygen saturation begins to decrease.
Practical Application of Pulse Oximetry
Practical Application of Pulse Oximetry