The Ultimate Vital Sign? Importance of Capnography in EMS Joshua Erdman, BS, CCEMT-P UW Emergency...

The Ultimate Vital Sign?Importance of Capnography in EMS

Joshua Erdman, BS, CCEMT-PUW Emergency Education Center

CO2 CO2

O2

CO2

O2 O2

The full cycleThe full cycle

CO2 CO2

O2

CO2

O2 O2

The full cycle and The full cycle and our other vital signsour other vital signs

RRPulse

EKG

BP

Pulse ox

Capnography

The full cycleThe full cycle

• Measuring CO2 allows us to look at:– Ventilation– Perfusion– Cellular metabolism

• And all instantly!

CapnographyCapnography

• Technology uses the Infrared absorbing capability of CO2 to determine the amount in a sample of air

• Gives us a measurement in mmHg

• Can graph this amount over time

TechnologyTechnology

• Two types– Mainstream

• Advantage: Fast

• Disadvantages: Bulky, usually only for intubated patients

– Sidestream• Advantages: Small samples, able to be used for spontaneous breathers

• Disadvantages: Slight time delay (<0.5 seconds)

Normal CapnogramNormal Capnogram

Capnogram Waveform

Phase Termed Variables Gas from

phase I A→B baseline A = completion of inspiration Large airwaysOropharynxnasopharynxB = beginning of expiration

phase II B→C expiratory upstroke

C = slowing of exhaled flow Intermediate airways mixes with phase I air

phase III C→D alveolar plateau D = end expiration = PETCO2 Mixed gas displaced by alveolar gas

phase IV D→E inspiratory downstroke

E= end inspiration Inspiratory gas has little CO2

Typical capnogramTypical capnogram

Capno vs. Pulse oxCapno vs. Pulse ox

IntubationsIntubations

• The #1 reason most paramedics know to use capnography

• AHA now identifies as the BEST way to confirm your tube (2010 guidelines)

Sudden change while bagging…Sudden change while bagging…

Sudden decrease!Sudden decrease!

Ventilation ratesVentilation rates

• Normal value should be 35-45 mmHg

• When ventilating,– if too LOW, you need to SLOW

– if too HIGH, you need to FLY (go faster)

ETCO2 Vent. rate

What the…?What the…?

What’s going on here?What’s going on here?

Exponential decrease in CO2Exponential decrease in CO2

CPR in progressCPR in progress

CPR usesCPR uses

• Effective compressions

• ROSC

• Termination of CPR

• Should I even have started?

Spontaneous breathersSpontaneous breathers

• Asthma vs. hyperventilation

HyperventilationHyperventilation

BronchospasmBronchospasm

Spontaneous breathersSpontaneous breathers

• Overdose

• CHF

• Ketoacidosis

• Sepsis

• Hyperthermia

• MI, especially right-sided or inferior wall

Hmmm…Hmmm…

In summary….In summary….

• Legal defense for intubations

• Immediate indication of changes in ventilation or perfusion

• Many clinical diagnosis possibilities when taken in consideration of other signs and symptoms

Thanks!Thanks!

• Joshua Erdman

• UW Emergency Education Center

• jerdman@uwhealth.org