Capnography Could MakeYou a Rock Star!

Mike McEvoy, PhD, RN, CCRN, NRPStaff RN – CTICU and Resuscitation Committee ChairAlbany Medical Center, New YorkEMS Coordinator – Saratoga County, New YorkEMS Editor – Fire Engineering magazine

Learning Objectives

Upon completion of the presentation the participant will Explain the physiology of capnography Discuss the clinical value of capnography in improving

patient outcomes Recall the role of capnography in the Guidelines for Emergency

Cardiac Care and CPR

What is Capnography?

Available for spontaneously breathing and for intubated patients

Uses Circuit Plugged into Monitor

Produces Waveform

Capnography

“Capnos” = Greek for smoke From the “fire of life” metabolism CO2 = the waste product of metabolism

Carbon Dioxide is a compound molecule 2 oxygen + 1 carbon 0.03% concentration in room air Odorless; heavier than air Green plants scavenge excess CO2

Oxygen Lungs alveoli blood

Muscles + Organs

Oxygen

Cells

Oxygen

Oxygen+

Glucose

ENERGY

CO2

Blood

Lungs

CO2

Breath

CO2

Physiology of Metabolism

SpO2 versus EtCO2

Oxygenation (Pulse Ox) O2 for metabolism SpO2 measures

% of O2 in RBCs Changes within 5 minutes

Ventilation (Capnography) CO2 from metabolism EtCO2 measures exhaled CO2

at point of exit Changes within 10 seconds

Oxygen Lungs alveoli blood

Muscles + Organs

Oxygen

Cells

Oxygen

Oxygen+

Glucose

ENERGY

CO2

Blood

Lungs

CO2

Breath

CO2

Physiology of Metabolism

Normal Capnography Waveform

Normal range is 35-45 mmHg Height = total CO2 Length = time/rate

45

0

Capnography Waveforms

45

0

45

0Hypoventilation

Normal

Hyperventilation

45

0

Capnogram Phases

Inhale

End-tidal

A B

CD

E

Capnogram Phases

End-tidal

Begin Exhale (dead space)

A B

CD

E

Capnogram Phases

End-tidal

End Exhale (plateau)

A B

CD

E

Capnogram Phases

End-tidal

End of the Wave of Exhalation

A B

CD

E

98

Sp02

The tube came out!

What about the Pulse Ox?

What Happened?

Waveform Shape

Bronchospasm (Asthma)

Mild Moderate

TestCapnography waveforms

Normal

Hyperventilation

Hypoventilation

Bronchospasm

45

0

45

0

45

0

45

0

Guidelines 2000

EtCO2 can be useful as a non-invasive indicator of cardiac output generated during CPR

Carbon Dioxide (CO2) Production

What If…

But, with High-Quality CPR…

Meet Howard Snitzer

54-years old, collapsed Jan 5, 2011 outside Don’s Foods in Goodhue, MN (pop. 900)

2 dozens rescuers took turns providing CPR for 96 minutes

6 shocks with first responder AED, 6 more shocks by Mayo Clinic Air Flight Medics

Transported to Mayo Clinic Cardiac Cath Lab

Why Not Quit?

Thrombectomy and stent to LAD

10 days in Mayo Clinic “The capnography

told us not to give up” EtCO2 averaged 35

(range 32 – 37)

Decision to Call the Code

120 prehospital patients in non-traumatic cardiac arrest EtCO2 had 90% sensitivity in predicting ROSC Maximal level of <10mmHg during the first 20 minutes

after intubation was never associated with ROSC

*Source: Canitneau J. P. 1996. End-tidal carbon dioxide during cardiopulmonary resuscitation in humans presenting mostly with asystole, Critical Care Medicine 24: 791-796

So What’s the Goal During CPR?

Try to maintain a minimum EtCO2 of 10

Push HARD (> 2”)FAST (at least 100)

Change rescuerEvery 2 minutes

AHA Hospital Guidelines – just released (2013)

Pre, Intra, Post arrest recommendations:1.Real time feedback at the point of care2.Shock early, don’t interrupt CPR, avoid hyperventilation, optimize depth3.BENCHMARK

AHA Hospital Guidelines – just released (2013)

Pre, Intra, Post arrest recommendations:1.Real time feedback at the point of care2.Shock early, don’t interrupt CPR, avoid hyperventilation, optimize depth3.BENCHMARK

AHA Guidelines – just released (2013)

Pre, Intra, Post arrest recommendations:1.Real time feedback at the point of care2.Shock early, don’t interrupt CPR, avoid hyperventilation, optimize depth3.BENCHMARK

AHA Guidelines – just released (2013)

Pre, Intra, Post arrest recommendations:1.Real time feedback at the point of care2.Shock early, don’t interrupt CPR, avoid hyperventilation, optimize depth3.BENCHMARK

AHA Guidelines – just released (2013)

Pre, Intra, Post arrest recommendations:1.Real time feedback at the point of care2.Shock early, don’t interrupt CPR, avoid hyperventilation, optimize depth3.BENCHMARK

Anesthesia

What Should Happen

Lungs (Good)

$tomach (Bad, Very Bad)

Anesthesia Litigation

Respiratory Damaging Events

American Society for Anesthesiologists: Closed Claims Project Database, 2010

The Answer? Capnography

Oct 1986 – American Society of Anesthesiology (ASA)

Capnography = basic standard of care for intra-operative monitoring

Colorimetric Capnometry Waveform Capnography

Recent Need for EtCO2

Guidelines 2005

EtCO2 recommended to confirm ET tube placement

Capnography Detects ROSC

Indications of Return of Spontaneous Circulation Sudden, sustained rise in EtCO2 from baseline Can occur before pulse or blood pressure are palpable

EtCO2 to Detect ROSC

90 pre-hospital intubated arrest patients 16 survivors 13 survivors: Rapid rise in exhaled CO2 was the earliest

indicator of ROSC Before pulse or blood pressure were palpable

Wayne MA, Levine RL, Miller CC. “Use of End-tidal Carbon Dioxide to Predict Outcome in Prehospital Cardiac Arrest” . Annals of Emergency Medicine. 1995; 25(6):762-767. Levine RL., Wayne MA., Miller CC. “End-tidal carbon dioxide and outcome of out-of-hospital cardiac arrest.” New England Journal of Medicine. 1997;337(5):301-306.

Guidelines 2010

Continuous quantitative waveform capnography recommended for intubated patients throughout peri-arrest period

In adults:1. Confirm ETT placement2. Monitor CPR quality

3. Detect ROSC with EtCO2 values

Guidelines 2010Evidence

Capnography Classes and Levels of Evidence1.Confirm ETT placement: Class I, LOE A2.Monitor CPR quality: Class IIb, LOE C3.Detect ROSC with EtCO2 values: Class IIa, LOE B

Definition of Classes and Levels of Evidence Used in AHA Recommendations

Class I Conditions for which there is evidence for and/or general agreement that the procedure or treatment is useful and effective.Class II Conditions for which there is conflicting evidence and/or a divergence of opinion about the usefulness/efficacy of a procedure

or treatment. Class IIa The weight of evidence or opinion is in favor of the procedure or treatment.Class IIb Usefulness/efficacy is less well established by evidence or opinion.Class III Conditions for which there is evidence and/or general agreement that the procedure or treatment is not useful/effective and in

some cases may be harmful.Therapeutic Recommendations 

Level of Evidence A Data derived from multiple randomized clinical trials or meta-analysesLevel of Evidence B Data derived from a single randomized trial or nonrandomized studiesLevel of Evidence C Consensus opinion of experts, case studies, or standard of care

Diagnostic RecommendationsLevel of Evidence A Data derived from multiple prospective cohort studies using a reference standard applied by a masked evaluatorLevel of Evidence B Data derived from a single grade A study, or one or more case-control studies, or studies using a reference

standard applied by an unmasked evaluatorLevel of Evidence C Consensus opinion of experts

©2010 American Heart Association, Inc. All rights reserved. Goldstein et al. Published online in Stroke Dec. 2, 2010

Classes of Evidence

I. Standard of care: Just do it!

II. Conflicting evidence: Maybe, maybe notIIa. Evidence favors benefit – Do itIIb. Evidence not so favorable – Think first

III. Not useful, maybe harmful: Don’t do it

Levels of EvidenceProof

A. A whole lotta proof: Best!

B. Some proof: Better than nothing

C. No proof: But some like the idea

Guidelines 2010Evidence

Capnography Classes and Levels of Evidence

1. Confirm ETT placement: Class I, LOE AJust do it, best proof

2. Monitor CPR quality: Class IIb, LOE CThink first, some like the idea

3. Detect ROSC with EtCO2 values: Class IIa, LOE BDo it, better than nothin’

Must We Follow Evidence?

BMJ, Dec 2003 Published cases of survivors falling

from airplanes No published evidence parachutes

actually work

Guidelines 2010Evidence

Capnography Classes and Levels of Evidence

1. Confirm ETT placement: Class I, LOE AJust do it, best proof

2. Monitor CPR quality: Class IIb, LOE CThink first, some like the idea

3. Detect ROSC with EtCO2 values: Class IIa, LOE BDo it, better than nothin’

?

TrueCPR®

Questions?