2 ~ 8 September 2012 (Week 5)
(Research)

Title of  Activity

Project Research- pulse oximetry 

Objectives 

-To know what is pulse oximetry and its relationship with ppg .

-make it as literature review .

Content Procedure 

surf the internet for information 

 Pulse Oximetry 

      

      Pulse oximetry is a non-invasive method allowing the monitoring of the saturation of a patient's hemoglobin.

A sensor is placed on a thin part of the patient's body, usually a fingertip or earlobe, or in the case of an infant, across a foot. Light of two different wavelengths is passed through the patient to a photo detector  The changing absorbance at each of the wavelengths is measured, allowing determination of the absorbances due to the pulsing arterial blood alone, excluding venous blood, skin, bone, muscle, fat, and (in most cases) nail polish. With NIRS it is possible to measure both oxygenated and deoxygenated hemoglobin on a peripheral scale (possible on both brain and muscle).

Reflectance pulse oximetry may be used as an alternative to transmissive pulse oximetery described above. This method does not require a thin section of the patient's body and is therefore well suited to more universal application such as the feet, forehead and chest, but it also has some limitations. Vasodilation and pooling of venous blood in the head due to compromised venous return to the heart, as occurs with congenital cyanotic heart disease patients, or in patients in the Trendelenburg position, can cause a combination of arterial and venous pulsations in the forehead region and lead to spurious SpO2 (Saturation of peripheral oxygen) results.

Pulse oximeter and its relationship with ppg 

           A pulse oximeter is useful in any setting where a patient's oxygenation is unstable, including   intensive care, operating, recovery, emergency and hospital ward settings, pilots in unpressurized aircraft, for assessment of any patient's oxygenation, and determining the effectiveness of or need for supplemental oxygen. Assessing a patient's need for oxygen is the most essential element to life; no human life thrives in the absence of oxygen (cellular or gross). Although a pulse oximeter is used to monitor oxygenation, it cannot determine the metabolism of oxygen, or the amount of oxygen being used by a patient.

 For this purpose, it is necessary to also measure carbon dioxide (CO2) levels. It is possible that it can also be used to detect abnormalities in ventilation. However, the use of a pulse oximeter to detect hypoventilation is impaired with the use of supplemental oxygen, as it is only when patients breathe room air that abnormalities in respiratory function can be detected reliably with its use. Therefore, the routine administration of supplemental oxygen may be unwarranted if the patient is able to maintain adequate oxygenation in room air, since it can result in hypoventilation going undetected.

Result &Analysis 

-Got the knowledge about the pulse oximetry .