1.NON-INVASIVE C A PNOGRAPHY ALS Blue In-Service Part III

2. Oxygenation and Ventilation

What is the difference?

3. Oxygenation and Ventilation Oxygenation (oximetry ) Cellular Metabolism Ventilation (capnography) CO 2 O 2 4. Oximetry and Capnography

Pulse oximetry measures oxygenation

Capnography measures ventilation and provides a graphical waveform available for interpretation

5. Oxygenation

Measured by pulse oximetry (SpO 2 )

• Noninvasive measurement

• Percentage of oxygen in red blood cells

• Changes in ventilation take minutesto be detected

• Affected by motion artifact, poor perfusionand some dysrhythmias

6. Oxygenation Pulse Oximetry Sensors Pulse Oximetry Waveform 7. Ventilation

Measured by the end-tidal CO 2

• Partial pressure (mmHg) or volume (% vol) ofCO 2in the airway at the end of exhalation

• Breath-to-breath measurement providesinformation within seconds

• Not affected by motion artifact, poor perfusion or dysrhythmias

8. Ventilation Capnography waveform CapnographyLines 9. Oxygenation and Ventilation

Oxygenation

• Oxygen for metabolism

• SpO 2measures% of O 2in RBC

• Reflects change in oxygenation within5 minutes

Ventilation

• Carbon dioxidefrom metabolism

• EtCO 2measures exhaled CO 2atpoint of exit

• Reflects change in ventilation within10 seconds

10. Oxygenation versus Ventilation

Monitor your ownSpO 2and EtCO 2

SpO 2waveform is in the second channel

EtCO 2waveform is in the third channel

11. Oxygenation versus Ventilation

Now hold your breath

Note what happens tothe two waveforms

How long did it take theEtCO 2waveform to go flat line? How long did it take theSpO 2to drop below 90%? SpO 2 EtCO 2 12.

Numeric reading: HR 100

Waveform:

13.

Numeric reading: HR 100

Waveform:

14. Capnography in EMS 15. Capnography in EMS

Low-flow sidestream technology

16. Using Capnography

Immediate information viabreath-to-breath monitoring

Information on the ABCs

• Airway

• Breathing

• Circulation

Documentation

17. Using Capnography

Airway

• Verification of ET tube placement

• Continuous monitoring ofET tube position

Circulation

• Check effectiveness of cardiac compressions

• First indicator of ROSC

• Monitor low perfusion states

Airway

• Circulation

18. Using Capnography

Breathing

• Hyperventilation

• Hypoventilation

• Asthma

• COPD

19. Using Capnography

Documentation

• Waveforms

• • Initial assessment

• • Changes with treatment

• EtCO 2values

• • Trends over time

• Waveforms

Trends 20. Why Measure Ventilation Intubated Patients

Verify and document ET tube placement

Immediately detect changes in ET tube position

Assess effectiveness of chest compressions

Earliest indication of ROSC

Indicator of probability of successful resuscitation

Optimally adjust manual ventilations in patients sensitive to changes in CO 2

21.

A 2005 study comparing field intubations that used capnography to confirm ETT placement vs. non-capnography use showed a 0% unrecognized misplaced ETT and 23% in the non-EtCO2 monitored group

Confirm ETI with waveform capnography!!

22. Why Measure Ventilation Non-Intubated Patients

Objectively assess acuterespiratory disorders

• Asthma

• COPD

Possibly gauge response to treatment

23. Why Measure Ventilation Non-intubated Patients

Gauge severity of hypoventilation states

• Drug and ETOH intoxication

• Congestive heart failure

• Sedation and analgesia

• Stroke

• Head injury

Assess perfusion status

Noninvasive monitoring of patients in DKA

24. End-tidal CO 2(EtCO 2 ) Ventilation Perfusion Pulmonary Blood Flow RightVentricle Left Atrium r r O x y g e n O 2 C O 2 O 2 V e i n A t e y 25. a-A Gradient r r Alveolus PaCO 2 V e i n A t e y Ventilation Perfusion a rterial toA lveolar Difference for CO 2 RightVentricle Left Atrium EtCO 2 26. End-tidal CO 2(EtCO 2 )

Normal a-A gradient

• 2-5mmHg difference between the EtCO 2 and PaCO 2in a patient with healthy lungs

• Wider differences found

• • In abnormal perfusion and ventilation

• • Incomplete alveolar emptying

• • Poor sampling

27. End-tidal CO 2(EtCO 2 )

Reflects changes in

• Ventilation - movement of air in andout of the lungs

• Diffusion - exchange of gases between the air-filled alveoli and the pulmonary circulation

• Perfusion- circulation of blood

28. End-tidal CO 2(EtCO 2 )

Monitors changes in

• Ventilation - asthma, COPD, airway edema, foreign body, stroke

• Diffusion- pulmonary edema,alveolar damage, CO poisoning, smoke inhalation

• Perfusion - shock, pulmonary embolus, cardiac arrest,severe dysrhythmias

29. Physiological Factors Affecting ETCO 2Levels 30. Interpreting EtCO 2and the Capnography Waveform

Interpreting EtCO 2

• Measuring

• Physiology

Capnography waveform

31. Capnographic Waveform

Normal waveform of one respiratory cycle

Similar to ECG

• Height shows amount of CO 2

• Length depicts time

32. Phase 1

First Upstroke of the capnogram waveform

Represents of gas exhaled from upper airways (I.e. anatomical dead space)

33. Phase 2

Transitional Phase from upper to lower airway ventilation, and tends to depict changes in perfusion

34. Phase 3

Represents alveolar gas exchange, which indicates changes in gas distribution

All increases of the slope of Phase 3 indicates increased maldistribution of gas delivery

35. Capnographic Waveform

Waveforms on screen and printoutmay differ in duration

• On-screen capnography waveform is condensed to provide adequate information the in 4-second view

• Printouts are in real-time

• Observe RR on device

36. Capnographic Waveform

Capnograph detects only CO 2 from ventilation

No CO 2present during inspiration

• Baseline is normally zero

Baseline 37. Capnogram Phase I Dead Space Ventilation

Beginning of exhalation

No CO 2present

Air from trachea,posterior pharynx,mouth and nose

• No gas exchangeoccurs there

• Called dead space

38. Deadspace 39. Capnogram Phase IBaseline Beginning of exhalation A B I Baseline 40. Capnogram Phase II Ascending Phase

CO 2 from the alveoli begins to reach the upper airway and mix with the dead space air

• Causes a rapid rise in the amount of CO 2

CO 2 now present and detected in exhaled air

41. Capnogram Phase II Ascending Phase CO 2present and increasing in exhaled air II A B C Ascending Phase Early Exhalation 42. Capnogram Phase III Alveolar Plateau

CO 2rich alveolar gas now constitutes the majority of theexhaled air