Capnography Flashcards
What is capnography?
Capnography is the study of carbon dioxide levels in exhaled air
Capno (combustion or smoke) + Ography (to study)
What is the process by which living cells produce energy?
Living cells burn glucose using oxygen to produce energy and carbon dioxide
What does capnography measure?
The amount of carbon dioxide exhaled with each breath
What is the term for the carbon dioxide exhaled with each breath?
End Tidal Carbon Dioxide (ETCO2)
How does capnography work?
It shines infrared light across exhaled air and measures the absorbed light to determine carbon dioxide levels
What are the two methods to measure capnography?
Nasal capnography and using a probe attached to a breathing tube
What does the capnography waveform represent?
A graph of CO2 against time
What should be done if there is a sudden absence of a capnography waveform?
Check on the patient urgently
What could a sudden absence of a capnography waveform indicate?
Carbon dioxide is not reaching the sensor, possibly due to a circuit break or cardiac arrest
What ETCO2 value is associated with poor survival rates during CPR?
ETCO2 under 10mmHg after 20 minutes of CPR
What does a sudden increase in ETCO2 during CPR predict?
Return Of Spontaneous Circulation (ROSC)
What should be done after a sudden increase in ETCO2 during CPR?
Continue compressions until the next rhythm analysis
What should be considered if ETCO2 is increasing while ventilating a patient?
Increase the ventilation rate
How can capnography be used to confirm correct placement of an airway device?
It can confirm correct placement of an endotracheal tube or supraglottic airway
What does a sudden drop in ETCO2 and a loss of waveform indicate?
Poor ventilation technique when using a bag valve mask
What does capnography inform us about?
Patients’ carbon dioxide levels
What does capnography not indicate about a patient?
Oxygenation levels
How is oxygenation measured?
Using pulse oximetry
