RCS Capnography

Question 1

4 Main Uses of Capnography

Answer 1

 Severity of asthma
 Monitoring head injured patients
 Cardiac arrest
 Tube confirmation

Question 2

numeric measurement of CO2

Answer 2

Capnometer

Question 3

a real-time waveform record of the concentration of carbon dioxide in the
respiratory gases

Answer 3

Capnogram

Question 4

the graphical representation of the concentration or partial pressure of expired CO2
during a respiratory cycle in a “waveform” format

Answer 4

Capnograph

Question 5

the level of (partial pressure of) carbon dioxide released at end of expiration.

Answer 5

End Tidal CO2 (ETCO2 or PetCO2)

Question 6

Limitation of CAPNOGRAPHY

Answer 6

• Critically ill patients often have rapidly changing dead
  space and Ventilation/perfusion mismatch
• Higher rates and smaller TV can increase the amount of
  dead space ventilation
• High mean airway pressures and PEEP(POSITIVE END-EXPIRATORY PRESSURE) restrict alveolar perfusion,
  leading to falsely decreased readings
• Low cardiac output will decrease the reading

Question 7

Factors that affect CO2 levels:
- INCREASE IN ETCO2

Answer 7

• Increased muscular activity
• Increased cardiac output
  (during resuscitation)
• Effective drug therapy for
  bronchospasm
• Hypoventilation

Question 8

Factors that affect CO2 levels:
- DECREASE IN ETCO2

Answer 8

• Decreased muscular activity
• Decreased cardiac output
  (during resuscitation)
• Bronchospasm
• Hyperventilation

Question 9

Normal Range of EtCO2

Answer 9

35-45 mmHg

Question 10

ETCO2 Less Than 35 mmHg =

• pH Increases (Alkalosis)

Answer 10

“Hyperventilation/Hypocapnia“

Question 11

ETCO2 Greater Than 45 mmHg =

• pH Decreases (Acidosis)

Answer 11

“Hypoventilation/Hypercapnia”

Question 12

CAPNOGRAPHY: Non-Intubated Applications

Answer 12

 Bronchospasms: Asthma, chronic obstructive
pulmonary disease, Anaphlyaxis
 Hypoventilation: Drugs, Stroke, congestive heart
failure, Post-Ictal
 Shock & Circulatory compromise
 Hyperventilation Syndrome: Biofeedback

Question 13

CAPNOGRAPHY: Intubated Applications

Answer 13

 Verification of Endotracheal Tube placement
 Endotracheal tube surveillance during transport
 Control ventilations during increased ICP(increase
intracranial pressure)
 Cardiopulmonary resuscitation

Question 14

Disposable detector
- Color changes in the presence of CO2
- This occurs when CO2 is exhaled, causing the pH to
decrease changing the disc from purple to tan.

Answer 14

Colorimetric

Question 15

Measures the percentage of CO2 that is present through the
third phases of expiration cycle. Based on CO2 diffusion from
pulmonary arterial blood carried to the pulmonary capillary
beds of the alveoli – where gas exchange occurs.

Answer 15

Infrared Monitoring

Question 16

This type of infrared monitoring tech., sensor located
directly in pt.’s
breathing circuit
- Used primarily on
intubated patients

Answer 16

Mainstream

Question 17

This type of infrared monitoring tech., Sample is removed
from pt.’s airway and
delivered to a distant
sensor.
- Can be used on
nonintubated
patients

Answer 17

Sidestream

Question 18

Square box waveform, ETCO2 35-45 mm Hg

Answer 18

Normal Waveforms

Question 19

Prolonged waveform
ETCO2 >45 mm Hg

Management:

Answer 19

Hypoventilation

• Assist ventilations or intubate as needed

Question 20

Shortened waveform
ETCO2 < 35 mm Hg

Management:

Answer 20

Hyperventilation

• If conscious gives biofeedback. If ventilating, give slow ventilations.

Question 21

During CPR sudden increase of ETCO2 above 10-15 mm Hg

Management:

Answer 21

ROSC (Return of Spontaneous Circulation)

• check pulse

Question 22

▪ Shark fin waveform
▪ With or without prolonged expiratory phase
▪ Can be seen before actual attack
▪ Indicative of Bronchospasm

Answer 22

Obstructive airway

Question 23

▪ Angled, sloping down stroke on the waveform
▪ In adults may mean ruptured cuff or tube too small
▪ In pediatrics tube too small

Management:

Answer 23

Patient breathing around ETT

• Assess patient, Oxygenate, ventilate and possible re-intubation

Question 24

Absence of waveform
Absence of ETCO2

Management:

Answer 24

Esophageal Tube

• Re-Intubate

Question 25

Square box waveform
ETCO2 10-15 mm Hg (possibly higher) with adequate CPR

Management:

Answer 25

CPR

• Change Rescuers if ETCO2 falls below 10 mm Hg

Question 26

A Capnogram that does not touch the baseline is indicative of a patient who
is rebreathing CO2 through insufficient inspiratory or expiratory flow
- Patient is re-breathing CO2

Management:

Answer 26

Rebreathing

• Check equipment for adequate oxygen flow
  If patient is intubated allow more time for patient to adjust

Question 27

CO2 dilates cerebral blood vessels, results in increase ICP

Answer 27

The Head Injured Patient

Question 28

Recognizing the head
injured patient and
titrating their CO2
levels to the “__________” range can help
relieve the untoward
effects of ICP

Answer 28

30-35 mmHg

Question 29

Increase in CO2 during CPR can be an
early indicator of

Answer 29

ROSC (Return of Spontaneous Circulation)

Question 30

Termination of Resuscitation: Non-survivors

Answer 30

<10 mmHg

Question 31

Termination of Resuscitation: Survivors

Answer 31

> 30 mmHg