Overcoming the challenge of the difficult to monitor Sp02 ......Apr 01, 2014 · monitoring SpO 2...
Transcript of Overcoming the challenge of the difficult to monitor Sp02 ......Apr 01, 2014 · monitoring SpO 2...
Overcoming the challenge of monitoring SpO2 in critically ill
patients
N GRAVENSTEIN MD5/21/19
Disclosure
I am a consultant for Philips.
Learning outcomes
1. Describe nasal ala pulse oximetry and its significant advantages by measuring oxygen saturation at the nasal ala.a) Describe how pulse oximetry works.b) Describe the rationale for pulse oximetry at the nasal ala site.c) Describe the advantages of nasal alar pulse oximetry.
2. Demonstrate how to use the nasal alar SpO2 sensor technology properly. a) Demonstrate how to use the nasal ala site for pulse oximetry. b) Demonstrate how to be a better SpO2 resource for your patients and others.
Who are we talking about?
We all have had patients where getting SpO2 is difficult
https://www.researchgate.net/publication/6535240_Acute_Deep_Hand_Burns_Covered_by_a_Pocket_Flap-Graft
https://www.jeffreysterlingmd.com/2016/01/20/straight-no-chaser-the-dos-and-donts-of-treating-frostbite-2/
How does SpO2 work?
Two LEDs One photodetector Photoplethysmogram Peak light absorption
detection Ratio red/infrared Adequate signal-to-noise
ratio Software lookup table for
saturation Display SpO2 value
A tiny % of the light picked up by the sensor represents the SpO2 signal for the monitor?
Sensor site composite of dynamic and static components affecting light absorption
Time
ABSO
RPT
ION • Absorption due to arterial blood
Absorption due to tissue
• Absorption due to venous blood
• Variable absorption due to pulse-added volume of arterial blood
common mistakes with pulse oximeters
https://opentextbc.ca/vitalsign/chapter/why-is-pulse-oximetry-used/
Good clinical practice tip
When looking at SpO2 think See pleth before O2
How equipment works.com
Troubleshooting your pulse oximeter
is the patient alive? is the patient in a low perfusion state? are the emitters and detector aligned? is there bright ambient light? does the sensor have power?
start with your patient and work your way back to the monitor
Pulse oximetry perfusion index
use the best finger!
Sample application
Sample application
It’s all about pulsatile blood flow
Low finger pulsatile blood flow
Local vasoconstriction (ie drug, temperature) Critical illness (i.e., low cardiac output) Low blood pressure VAD
Thermal image (healthy adult in cold room)
1-2 minutes
45 minutes
Thermal image (healthy adult in cold room)
Thermal image (healthy adult in cold room)
1-2 minutes 45 minutes
Infrared thermometry demo
Vasoconstrictive distal ischemia
Nasal alar pulse oximetry sensor
Protected circulation areas
What in the world is an ala?
Internal carotid branch
External carotid branch
Blood supply to the ala
• The nasal ala has little sympathetic innervation
courtesy of richard melker
The nasal alar vasculature responds differently to vasopressors
What's different about the ala probe?
same technology as finger probe same algorithm same waveform bigger signal to noise ratio (AKA perf or perfusion index) different applicator self-retaining
Nasal alar sensor application
Apply with T-shaped pad and wire on outside of ala
Ala is back part of nose, closest to cheek
Remove applicator
Position sensor fully on to ala Secure sensor; Check
or rotate site periodically
BENEFITS
BIGGER signal (with protected circulation, higher perfusion index) FASTER responses than a finger sensor to declining SpO2
FASTER feedback that an intervention is having desired effect BETTER performance in low peripheral perfusion states
Response time and signal size demo
Questions?
How many things can you learn from a pulse oximeter?
How many things can you learn from a pulse oximeter?
1 - O2 sat2 - Heart rate3 - Heart rhythm4 - If sat changing5 - If heart rate changing6 - Systolic bp7 - Hypovolemia8 - If patient alive9 - If CPR is making an effective pulse
At least 9