ISCE Station 1: Anaesthetic Care Flashcards
1
Q
What does a pulse oximeter measure?
A
- detects pulsatile blood eg. arterial flow
- calculates a pulse
- measures the amount of oxygen absorbed by haemoglobin
- generates a waveform called a PHETHYSMOGRAPH
2
Q
Look at the monitor. Which waveform represents the pulse oximeter?
A
n
3
Q
What are the normal readings for a pulse oximeter?
A
95-99% oxygen saturation
60-100 pulse rate
4
Q
What factors would you consider during applying the pulse oximeter?
A
- dark nail polish or false nails
- use of tourniquet or blood pressure cuff on same limb
- shaking or shivering
5
Q
Why would dark nail polish or false nails give an inaccurate pulse oximeter readings?
A
- Generally gives a lower reading
- Nail polish may absorb or block the light which tampers with the infared light so the sensors pick up a lower reading of the light that is transferred through the tissues.
6
Q
Why would the use of a tourniquets or blood pressure cuffs give an inaccurate pulse oximeter reading?
A
- Generally provides a lower or absent reading
- Tourniquets result in decreased perfusion meaning there is less oxygenated blood reaching the tissues, providing a lower oxygen saturation reading even if the rest of the body is adequately oxygenated.
- Pulse oximeters rely on detecting the small, rhythmic changes in blood volume with each heartbeat. The pulsatile flow is diminished or stopped altogether in the area where the pulse oximeter is placed with the use or a tourniquet.
7
Q
Why would shaking or shivering give an inaccurate pulse oximeter reading?
A
- Generally provides a higher reading
- Shiving or shaking can create a signal that mimics multiple pulses per heartbeat
- Can cause the sensor on the finger to shift slightly, leading to inconsistent light detection, causing the device to miscalculate the oxygen saturation.
8
Q
Why is a pulse oximeter important for a patient undergoing anaesthesia & surgery?
A
- Anesthesia can suppress a patients breathing or interfere with the normal exchange of oxygen in the lungs and it also can affect heart rate leading to bradycardia or arrhythmias.
- Continuously monitors a patients oxygen saturations and heart rate to ensure the patients blood remains adequately oxygenated and detect any cardiovascular instability during the surgery.
9
Q
What does capnography measure?
A
10
Q
What is a normal capnography reading?
A
11
Q
What factors would affect a capnography reading?
A
12
Q
A
13
Q
Why would
A
