LO6 End Tidal Flashcards
why do we put end tidal on everyone
- Want to see whats going on in the lungs (bronchoconstriction)
- Want to see the effects of treatments
- Capnography (capnometry)
The measurement of carbon dioxide in exhaled breath
- Capnometer
The numeric measure of CO2
- Capnogram
The wave form produced with inspiration & expiration
- ETCO2 define
the level of partial pressure of carbon
-PaCO2
Partial pressure of CO2 in arterial blood
3 things needed for 02
- Cardiac output
- Ventilation: gas exchange at the alveoli wall
- Metabolism: what the cells need to use oxygen
- CO2
is the “Gas of Life” produced from “The fire of life” metabolism
ETCO2
- Provides an immediate, real time, picture of the pt.’s condition
- Capnography will show immediate apnea
- Directly related to the ventilatory status of the pt.
SPO2
- Delayed, SpO2 can show high saturations for several minutes
- SPO2 will not show immediate apnea
- Directly related to oxygenation of the pt.
What else can ETCO2 tell us?
Not only can ETCO2 measure ventilation but . . . .
- It also indirectly measures metabolism & circulation
- An increased metabolism will
increase the production of carbon dioxide & increasing levels on the monitor
- A decreased metabolism will
decrease the amount of CO2 delivered to the lungs & decreases levels on the monitor
Intubated Capnography Patients
- EtCO2 is directly related to the ventilation status & can be used in intubated as well as non-intubated pt.’s
- Capnography in Intubated pt.’s can be used to:
o Verify ETT placement
o Monitor ETT position
o Assess ventilation and treatments
o Evaluate resuscitative efforts during CPR
Non-Intubated Capnography Patients
- Asthma & COPD
- CHF/Pulmonary Edema
- CPAP pt.’s
- Pulmonary Embolus
- Head Injury
Capnography Values
Hyperventilation / Hypocapnia
- > 45mmHg
- Respiratory Acidosis
In-accurate readings may be due to;
- Poor positioning of NC capnofilters
- Obstructed nares
- Mouth breathers
- O2 by mask may lower reading by 10% or more
Increased ETCO2
Due to Increased CO2 Production - Fever - Burns - Hyperthyroidism - Seizure - Bicarbonate Tx - Return Of Spontaneous Circulation - (ROSC) - Release of Tourniquet / Reperfusion - Decreased ETCO2 - Increased CO2 Clearance o Hyperventilation - Exercise - Sick
Decreased ETCO2
Decreased CO2 production - Hypothermia - Sedation - Paralysis Decreased delivery to the lungs - Decreased cardiac output
Normal Waveform
- Straight boxes are good
- Length of wave = Time
- Height of wave = CO2 Level
- CO2 is a result of
Metabolism
Hyperventilation Waveform
CO2 goes down
- Wave forms start getting lower
- Anxiety
- Bronchospasm
- PE
- Increased ventilation
- Remember to look at the trend not just the number
Causes for CO2 going down
- Hypothermia
- Decreased Metabolism
- Decreased Pulmonary perfusion