SPO2

Saturation of Peripheral Oxygen (SpO2) is a measure of the percentage of hemoglobin saturated with oxygen and can be measured by oximetry or through blood tests

Spo2 is the percentage of oxygenated hemoglobin (hemoglobin containing oxygen) compared to the total amount of hemoglobin in the blood (oxygenated and non-oxygenated hemoglobin).

Normal SpO2 values vary between 95 and 100%. And according to AHA it is 94% to 99% FOR COPD ITS 88% - 92%

Let us also know about the Normal Hb level:

• Male = 13.5-17.5 g/dl

• Female = 11.5-15.5 g/dl

• Child = 11.0-13.5 g/dl

• Baby = 9.5-12.5 g/dl

• New born = 15.0-21.0 g/dl

Hemoglobin is a protein that carries oxygen in the blood. It is found inside red blood cells and gives them their red colour.

SpO2 can be measured by Pulse oximetry, an indirect, non-invasive method (meaning it does not involve the introduction of instruments into the body).

It works by emitting and then absorbing a light wave passing through blood vessels (or capillaries) in the fingertip.

A variation of the light wave passing through the finger will give the value of the SpO2 measurement because the degree of oxygen saturation causes variations in the blood’s colour.

In simple way how will you manage calculate the total HB percentage in body lets us see, take an example If your spo2 says 98%, this means that each red blood cell is made up of 98% oxygenated and 2% non-oxygenated hemoglobin.

Good blood oxygenation is necessary to supply the energy your muscles need in order to function, which increases during a sports activity. If your SpO2 value is below 90%, that could be a sign of poor blood oxygenation, also called hypoxia.

As we are talking about HB let me mention about carbon monoxide poisoning

•Carbon monoxide poisoning typically occurs from breathing in carbon monoxide at excessive levels. Symptoms are often described as “flue-like” and commonly include headache, dizziness, weakness, vomiting, chest pain and confusion. Large exposures can results in loss of consciousness, arrhythmias, seizures or death. And the classically described “cherry red skin” rarely occurs.

•What happens during that time?

When body induce excessive carbon monoxide then CO will bind with HB it produce compound of carboxyhemoglobin , which decreased the transport, delivery and utilization of oxygen by the body. (show the diagram how it will be looking in monitor spo2)

Let see how The clinical important of pulse wave analysis:

•Normal pulses wave

•Small and weak pulse wave

•Large and bounding pulses wave

•Bisferiens /chaotic pulses wave

•Pulses alternans wave

•No dicrotic notch wave

Now lets discuss the waveform one by one

No dicrotic notch

Physiological cause

•Increase dicrotic notch

Possible disease

•Coronary heart disease (CAD)

PULSES alternanse

Physiological cause

•Pulse amplitude varies from peak to peak

•Rhythm basically regular

Possible disease

•Left ventricular failure

Bisferiens type/chaotic

Physiological changes

Arrhythmia

Motion artefact

Possible disease

•VT

•VF

Background movement

Large and bounding

Physiological causes

•Increase stroke volume

•Decrease peripheral resistance

Possible disease

•Fever

•Anemia

•Hyperthyroidism

•Aortic regurgitation

•Bradycardia

•Atherosclerosis

•Traumatic brain injury

Small and weak pulses wave

Physiological cause

•Decreased stroke volume

•Increase peripheral resistance

Possible disease

•Heart failure

•Hypovolemia

• Severe aortic stenosis