Blood Gases .... help? (1 Viewer)

w00dy.

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hello all.

i have a quick question and i hope that someone out there can help me with the answer or direct me in the right direction as to where i could find the answer. for my assessment task

sooo.. here goes...

describe and explain the conditions under which these technologies are used.
the technologies being; arterial blood gas analysis, pulse oximetry.

thanks muchlies
 

ari89

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Pulse Oximeters:
A sensor attached to the person measures the absorption of light by the blood. This is used to tell the concentrations of oxygen in the blood as blood with different levels are of a different colour.

Pulse oximetry is used to monitor the level of oxygen in a person's blood during heavy sedation or anesthesia. This device is also used when a person is on a ventilator, artificial breathing machine, during stress testing, in sleep laboratories, when checking the body's response to different medications or to monitor a person with asthma or who is having trouble breathing.
ABG:
Unlike the above method, ABG requires a sample of the blood to be obtained. An analysis machine measures O2 content and saturation as well as the bicarbonate content and related pH.
Its main use is for lung disease (pulmonology), for assessing the lungs ability to deliver oxygen and and get rid of CO2.
 

+Po1ntDeXt3r+

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to add to ari89

Measurements:
ABG:measure partial pressures of gases, as well as Hb O2 saturation

pulse oximetry: measures just Hb O2 saturation.. u can use this for like simple resp problems or heart problems ==> breathing difficulty

problems:
ABG: u shove a probe into an artery usually the radial artery... (area near where ure wrist watch is..).. so they can bleed out, lose tissue perfusion-->tissue death... its very invasive.. but good for metabolic problems

Pulse Ox: CO poisoning, abnormal Hb shapes, nail polish.. it is useless then.. cannot be used for diagnosising cause of hyperventilation problems

Extra stuff (this is for if u want to know more):
- by measuring O2 levels in pulso ox.. u are just monitoring tissue perfusion.. but not ventilation..

lung function is based on both ventilation and perfusion... as O2 and CO2 transport are by different systems.. O2= mostly on Hb .. and CO2= about 12% in the Hb.. and the rest of CO2 dissolved in blood .

So
pulse ox= Hb hence O2 measurements which is perfusion/oxygenation..
but since CO2 partial pressure is not recorded .. ventilation is not recorded.. this is went ABG is used
 

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