cc - etco2 and waveform capnography

Traumatic Case Study

Fall Conference 2012

Johnny05-26 0640

Car at highway speed loses control in a rain storm and hits a tree. 4 passengers in the car. 1 was ejected.

3 restrained passengers are considered stable. Johnny, 10 year old male, is found unresponsive with agonal respirations at the scene. He is intubated with a size 5 ET and the tube is secured 15 cm at the lip.

0715 –

Patient arrives to local ED intubated, with a C-collar in place, and obvious head, chest and femur injuries.

Johnny ET tube placement is confirmed by the trauma surgeon and placed on the ventilator. ED physician orders an emergent CT-Scan of the head, chest, and pelvis.

Pt. is manually ventilated to CT.

Seven minutes after moving the patient to the CT table the monitor is alarming.

HR – 52 (sinus bradycardia)BP – 76/48SpO2 – 78%Patient looks cyanotic

Clinical problem? Treatments?

JohnnyD – ET is secured, 12 cm @ the lip

Air leak is noted from the mouth

O – Can manually ventilate easilyCan freely pass a suction catheter

P – Diminished BS bilaterallyPoor chest rise

E – Removed from ventilator and ventilating with resuscitation bagon 100% oxygen

Problem? Actions?

JohnnyJohnny is emergently reintubated. Person performing the intubation takes a long time due to crowding and lack of room.

After intubating assessment reveals:

•5 ET, placed 15 cm @ lip•Poor breath sounds•HR and SpO2 decreasing•Air is heard in the stomach•Pt. vomits before ET is removed

Pt. reintubated. Placement confirmed by auscultation. Suctioning gastric contents from the ET.

Johnny

Pt. transported back to the ED from CT Scan and returned to ventilator.

•HR – 118•RR – 18 by vent•B/P – 102/66•T – 97.6•SpO2 – 93%•BS – Rhonchi

Complications?

Johnny

5-26 1025

Nurses respond to a monitor alarm. SpO2 fell suddenly to 76%.Despite manual ventilation and suctioning the SpO2 continues to fall.

Vitals:HR – 140BP – 156/96SpO2 – 65%BS – RhonchiColor – cyanotic

1028 – bradycardiac, agonal respiratory efforts, cyanotic, code blue.

Johnny

5-26 1118

Resuscitative efforts stopped after 45 minutes of CPR and 15 minutes of asystole.

Patient is stiff and cold. Skin color is purple.

What could have been the cause of this arrest? Is there anything we could have done better to improve outcome?

Objectives

• Identify the uses waveform capnography and how it can improve patient care.

• Explain the cause of the CO2 gradient that can be found with waveform capnography.

• Discuss the use of waveform capnography in cardiopulmonary resuscitation.

Capnography Basics

Resuscitation Trends: EtCO2

Timeline:

• Developed in 1960’s• Used by Anesthesia since 1970’s• Standard of Care in OR 1991

EtCO2 Technology

• Capnographs utilize infrared (IR) technology– CO2 molecules absorb IR light energy of a

specific wavelength– Amount of energy absorbed = CO2 concentration

• Infrared is particularly appropriate for measuring CO2

– CO2 has a strong absorption band in the infrared spectrum

– In the ICU, the CO2 band is distinct enough from other gases to minimize interference

Application

SpO2 vs. EtCO2

PCA / Moderate Sedation

Intubation

Advantages:• Evaluate EtCO2 waveforms• Analyze reading of exhaled CO2• Monitor for tube placement and early deterioration• Reassess for improvements after treatments

Cellular Metabolism of food into energy - O2 consumption & CO2 Production

Transport of O2 & CO2 between cellsand pulmonary capillaries

Ventilation conveys CO2 and O2 between the alveoli and pulmonary capillaries

CO2 The Big Picture

O2

CO2 CO2

CO2

Normal Arterial & ETCO2 Values

Arterial CO2 (PaCO2)from ABG

ETCO2from Capnograph

Normal PaCO2 Values:

35 - 45 mmHgNormal ETCO2 Values:

30 - 43 mmHg

ABGs are the “gold standard” but only offer a snapshot in time of the PaCO2; whereas ETCO2 offers the clinician constant

monitoring of and the ability to trend the CO2

Values

In healthy lungs the normal PaCO2 to ETCO2 gradient is 2-5 mmHg

In diseased lungs, the gradient will increase due to ventilation/perfusion mismatch, as much as 25 mmHg.

V/Q Ratio

Ventilation-Perfusion RelationshipsRelationship between ventilated alveoli and blood flow in the

pulmonary capillaries

Shunt perfusionAlveoli perfused but not ventilated

CO2 O2

NormalVentilation and

perfusion is matched

Deadspace ventilationAlveoli ventilated but not

perfused

Normal V/Q

CO2 O2

Blood

Alveoli

ETCO2 / PaCO2

Gradient = 2 to 5 mmHg

Shunt Perfusion – Low V/Q

ETCO2 / PaCO2

Gradient =4 to 10 mmHg

Anything that causes the alveoli to collapse or is

alveolar filling

Blood

Alveoli

No exchange of O2 or CO2

Dead Space Ventilation: High V/Q

ETCO2 / PaCO2

Gradient is large(as much as 20-25 mmHG)

No exchange of O2 or CO2

. .Anything that causes a

significant drop in pulmonary blood flow

Alveoli

50

0

25

CO2 mmHg

E

D

A B

C

Normal Capnogram Waveform

CO2 (mmHg)

0

25

50

Alveolar Plateau established

No Alveolar Plateau

Alveolar Plateau

Capnography: waveforms

50

0

25

RR – 18EtCO2 - 43

RR – 26EtCO2 - 56

RR – 4EtCO2 - 11

RR – 14EtCO2 - 34

Capnography: waveforms

CO (m m Hg)2

0

37

50 Real-Tim e Trend

CO (m m Hg)2

0

37

50 Real-Tim e Trend

RR – 16EtCO2 - 48

RR – 28EtCO2 - 30

Capnography: waveforms

25.2

Your patient’s PaCO2 was 45 mmHg on the most recent ABG.

EtCO2 monitor reads 25. Why are they not correlating? Is the equipment not working?

Johnny05-26 0640

Car at highway speed looses control in a rain storm and hits a tree. 4 passengers in the car. 1 was ejected.

3 restrained passengers are considered stable. Johnny, 10 year old male, is found unresponsive with agonal respirations at the scene. He is intubated with a size 5 ET and the tube is secured 15 cm at the lip.

0715 –

Patient arrives to local ED intubated, with a C-collar in place, and obvious chest and femur injuries.

JohnnyET tube placement is confirmed in the trauma room by capnography and placed on the ventilator. ED physician orders an emergent CT-Scan of the head, chest, and pelvis.

Pt. is manually ventilated to CT.

Shortly after moving the patient to the CT table the monitor is alarming.

EtCO2 – 18 HR - 108RR – 6 SpO2 – 96%

CO (m m Hg)2

0

37

50 Real-Tim e Trend

Clinical problem? Treatments?

Johnny

D – Based off assessment of EtCO2 waveform it is suspected and confirmed that the ET is displaced. Pt. was intubated with a 5 cm tube to 15 cm @ lip.

Actions?

JohnnyJohnny is emergently reintubated. Person performing the intubation takes a long time due to crowding and lack of room.

After intubating assessment reveals:

•5 ET, placed 15 cm @ lip•Poor breath sounds

Pt. reintubated.

CO (m m Hg)2

0

37

50 Real-Tim e Trend

Waveform after reintubation:

C O (m m Hg)2

0

37

50 R eal-Tim e Trend

Johnny

Actions?

JohnnyPt. transported back to the ED from CT Scan and returned to ventilator.

•HR – 118•RR – 18 by vent•B/P – 102/66•T – 97.6•SpO2 – 93%•BS – few crackles bilateral•EtCO2 – 24•PCO2 - 46

Actions?Complications?

Johnny

5-26 0915

Being a therapist trained in capnography you alert the doctor do the difference of the EtCO2 to the actual PCO2. You explain that it is most likely not a problem with the machine but a clinical problem with the patient. You suggest he be evaluated for a Pulmonary Embolus since he was a trauma patient.

Pt. is returned to CT for a repeat chest scan with contrast. Massive PE found.

0945 – trauma doctor notified and pt. taken to surgery immediately to remove the clot.

Johnny5-26 1115

Pt. returned to the ICU following removal of pulmonary embolus and repair of his femur.

Pt. is extubated after 2 days of mechanical ventilation.

Pt. continues to improve and is discharged home in 10 days.

Johnny’s uncle is a wealthy business man and purchased 12 EtCO2 monitors for the hospital 6 months later.

Resuscitation Trends: Changes in EtCO2

2010 Guidelines by the American Heart Association

Case of Howard Snitzer

01/15/2011 1045

54 year-old male, Howard Snitzer, collapses after complaining of chest pain. Bystanders call 911 and initiate CPR.

1105

Flight team lands on the scene. Find the patient to be in ventricular fibrillation. Flight crew perform immediate defibrillation and continue CPR.

Case of Howard Snitzer

• Despite continued CPR, defibrillations, and doses of epinepherine/amiodarone Mr. Snitzer remains in pulseless arrest.

1115

• Medflight nurse reports progress to local ED physician. ED physician tells the nurse to stop CPR efforts since the patient has been pulseless for 30 minutes.

• Thoughts?

Resuscitation Trends: EtCO2

Resuscitation Trends: EtCO2

Circulation:

• 30% of normal cardiac output (CO) with chest compressions• 30% of normal blood flow through the pulmonary system• 30% of normal EtCO2 return• Normal EtCO2 – 30-43 mmHg• 30 x .3 = 10

Effective chest compressions with produce an EtCO2 value above 10

Resuscitation Trends: EtCO2

• EtCO2 value >10 mmHg with compression = viable heart and brain

Case of Howard Snitzer

http://m.npr.org/news/front/139670971?singlePage=true

Resuscitation Trends: EtCO2

AHA Resusciation/EtCO2 Guidelines:

• Maintain high quality CPR, EtCO2 > 10 mmHg• Detect ROSC• Feedback on length of resuscitation