Pulse oxymetry Flashcards
What is pulse oxymetry?
A percutaneous measurement of functional peripheral haemoglobin saturation by oxygen (SaO2), measured in percentages.
What can the colour of blood tell us?
The haemoglobin saturation by oxygen
How can you differ oxygenated blood from deoxygenated blood based on colour?
Oxygenated haemoglobin absorbs less red light –> brighter red, than deoxygenated haemoglobin which absorbs more infrared light –> darker red
The difference between saturated and deoxygenated haemoglobin is measured by?
Pulse oxymeter
What does a pulse oxymeter calculate?
Functional oxygen saturation of the hemoglobin and the pulse frequency.
When and where is there a higher light absorption of venous blood?
During diastole
soft tissues, bones and pigments
When is there a higher light absorption of arterial blood?
During systole
How does the oxymeter consist of?
Consists of a diode and photodetector
How does the oxymeter function?
Rays are transmitted from the diode through the skin, soft tissues and blood,to the photoreceptor.
What is the initial goal in emergency medicine?
To maintain adequate oxygen delivery to the tissues.
How is adequate oxygenation of blood assured?
By an oxygen mask, flow-by, nasal insufflations, trans-tracheal catheter, oxygen cage and/or positive pressure ventilation.
Oxygen tissue delivery require…?
an adequate cardiovascular function.
Three major causes of inadequate tissue perfusion are?
Hypovolemia – decreased volume of circulating blood in the body.
Sepsis –> the body’s over-active and toxic response to an infection.
Inadequate cardiac function.
In veterinary medicine the most common cause of hyperfusion is?
Hypovolemia
What are many devices sensitive to?
Movement, muscular tension in the fingertip.
