Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Clinical Applications of Capnography

Clinical Applications of Capnography

Megan Jacobson

on 7 November 2016

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Clinical Applications of Capnography

Confirming Endotracheal Intubation
No single method to confirm placement of the ETT with 100% accuracy.
Using capnography as an adjunct to other confirmation methods can quickly detect esophageal intubation.
Clinical Applications of Capnography in the ICU
Confirming Endotracheal Intubation
Monitoring During Repositioning
Assessment of Cardiac Output
Prognostic Indicator During CPR
Non-invasive Monitoring of Ventilation
Detection of Gastric Tubes Inadvertently Placed in the Trachea
Clinical Applications of Capnography
Monitoring During Repositioning
accidental extubation
kinking of the ETT
obstruction of ETT
Assessment of Cardiac Output
Prognostic Indicator During CPR
Clinical Applications of Capnography
Megan Jacobson M.S., R.R.T.
Non-invasive Monitoring of Ventilation
Detection of Gastric Tubes Inadvertently Placed in the Trachea
Gastric tubes can be misplaced in the trachea. Especially during nasal insertion and with spontaneously breathing non-intubated patients.
Colorimetric chemical indicator
Example of Monitoring Cardiac Output
15 year old intubated patient on mechanical ventilation in the ICU monitored with capnography.
Partial Obstruction, Kinking of ETT
BP 122/86, PaCO2 51, PETCO2 46. (a-ET)PCO2 5mmHg
BP dropped after sedation 114/65. PaCO2 55, PETCO2 48. (a-ET)PCO2 difference increased to 7 due to the decrease in CO.
BP improved 124/83, PaCO2 51, and PETCO2 46 decreasing the difference back to 5mmHg.
(a-ET)PCO2 difference of 2-5mmHg is normal
If following the ETCO2 without arterial CO2 monitoring, remember that decreases in ETCO2 can be from a decreased cardiac output.

reasonable to consider waveform capnography in intubated patients to monitor CPR quality, optimize chest compressions, and detect return of spontaneous circulation (ROSC).

Exhaled CO2 correlates with pulmonary perfusion. Even with absent pulses, the presence of at least 10mmHg of exhaled CO2 can confirm that some pulmonary blood flow is present.

If ETCO2 is <10mmHG the CPR is ineffective.

An ETCO2 <10mmHG during CPR it is a poor prognostic indicator.
Volume Capnography
calculate physiologic dead space (VD/VT)
monitor alveolar minute ventilation (MValv) (effective ventilation reaching the alveoli for gas exchange)
monitor CO2 elimination (VCO2). Changes in VCO2 alert you to changes in alveolar ventilation.
Monitoring MValv and VCO2 can be useful to determine optimal PEEP in mechanically ventilated patients. With incremental increases in PEEP, the VCO2 and MValv will increase when alveolar recruitment occurs.
MValv and VCO2 also useful during the weaning process and can detect decreases in effective ventilation.
If undetected, feeds and medications are administered into the trachea putting the patient at risk for aspiration pneumonia.
Capnography is a quick and reliable method for detecting life-threatening conditions.

The benefits of capnography can be applied for patients in the following clinical settings:
intensive care units
emergency medicine
procedural sedation
postoperative period
recommend continuous waveform capnography in addition to clinical assessment as
the most reliable method
of confirming and monitoring correct placement of an endotracheal tube.
if waveform capnography is not available, a nonwaveform exhaled CO2 monitor in addition to clinical assessment is
Presence of CO2=Yellow
False Negative Results(low cardiac output)
False Positive Results (gastric acid, lidocaine, epinephrine)
AHA 2010 CPR guidelines:
Capnography can quickly identify:
Accidental extubation, Complete obstruction
CO =
CO2 in blood stays the same
Increase dead space (Lack of perfusion to ventilated alveoli) causes decreased ETCO2.
Decreased CO causes increased (a-ET)PCO2 Difference
AHA 2010 Guidelines for CPR
Sodium Bicarbonate:
causes transient increase in CO2, can be mistaken for ROSC.
Decreased ETCO2 because it increases afterload & BP, but decreases CO.
ETCO2 to predict PaCO2
reduce number of arterial punctures
guidance for weaning MV
continuous monitoring of ventilation versus intermittent blood gases
detect sudden changes, life-threatening conditions
monitor effectiveness of bag-mask ventilation
determine effectiveness of therapies
detect improvements in effective alveolar ventilation (a-ET) (Volume Capnography)
Volume capnography incorporates the use of a flow sensor with the CO2 sensor.
Capnography in the Prehospital Setting
Waveform Analysis
Waveform Analysis
Waveform Analysis
Capnography during Conscious Sedation & Postoperative Monitoring
Patients are at risk for airway obstruction, hypoventilation and apnea.
Waveform Analysis
Optimization of Ventilation
spontaneous ventilation
manual with bag mask ventilation
mechanical ventilation
Confirm ETT placement
Monitor effectiveness of CPR
Ensure effective ventilation is delivered & Avoid Hyperventilation
Determine when to administer narcan to OD patient
Reliability of ETCO2 depends on severity of lung disease, cardiac output, and airway issues (misplaced ETT, obstruction, leaks in the system, leaks around ETT, and leaks with non-intubated patients)
Assess waveforms to determine causes of low ETCO2s
initial comparison of ETCO2 to PaCO2 required
increase (a-ET) difference with low cardiac output
increase (a-ET) difference with severe V/Q mismatch
Pulse oximetry is not enough.
Capnography will detect hypoventilation or apnea before hypoxia occurs.
Non-intubated patients can be monitoring with sidestream sampling technology. Sample lines can be attached to simple masks or nasal cannulas.
Example: A patient in the ICU for postoperative monitoring was resting comfortably with SpO2 >95% on 2L NC. She was receiving morphine for pain management. The bedside nurse noticed a slight drop in SpO2 to 90% and assessed the patient. The patient was difficult to arouse and a blood gas was obtained. The patient's PaCO2 was >90mmHg. If this patient's respiratory depression had been detected several hours earlier with capnography, corrective measures would have prevented further hypoventilation by adjusting dosages or administering narcan sooner.
disconnection from breathing circuit
complete obstruction of airway/circuit
accidental esophageal intubation
accidental extubation
apnea, cardiac arrest
leaks in the circuit
leaks around ETT
40% Leak
80% Leak
Shark Fin
partially kinked ETT/circuit
foreign body in airway
asthma, COPD, bronchospasm
Severe airway obstruction
After 1 bronchodilator given via SVN
After 2 treatments
Images from: http://emscapnography.blogspot.com/
Analyzing the waveform is essential before relying on interpretation of the ETCO2 value.

Several factors can cause erroneously low ETCO2 values and the only way to detect those factors is by analysis of the waveform.
Normal Waveforms
Waveform will not have the characteristic shape with fast rates and low volumes (peds), or in non-intubated patients
phase O -inspiration
phase I -anatomic dead space, expiration begins
phase II -alveolar gas begins to mix with dead space gas
phase III -alveolar plateau, completion of expiration. Slope continues to rise slightly as CO2 from low V/Q areas empty
alpha angle
increased angle
with obstruction
beta angle
increased angle
with rebreathing
Full transcript