Daniel Davis, MD

UCSD Center for Resuscitation Science

New Frontiers inResuscitation

Science

Key Concepts

• Compressions

• Ventilations

• Pressors

• PetCO2

• Post-resuscitative care

1. Optimal Compressions

The Primary Directive

Chest compressions should be performed

from the moment of arrest until return of

spontaneous circulation is assured.

Kern (2002) Circulation

Prime the Pump!

Christenson (2009) Circulation

Stay on the chest!

* Adjusted for: age, gender, bystander CPR, public location, response time, compression rate

Compression Interruptions

• Initiating compressions

• Rhythm analysis

• Shock sequence

• Pulse check

• Intubation

• Vascular access

Bystander CPR

ECG Filtration

Return of Spontaneous Circulation

Electrical(HR)

Mechanical(PetCO2)

Stiell et al (2008) AHA Scientific Sessions

Deeper Compressions

Aufderheide (2005) Resuscitation

Good Recoil

Rate

0 to 80 81 to 120 121+ (N=65) (N=478) (N=122)

38 mm 49% 44% 69%

38-51 mm 28% 44% 30%

>51 mm 23% 12% 2%

Depth

Stiell et al (2008) AHA Scientific Sessions

Rate vs Depth

CPR Process

Code # 79265 (11/28/12) Code Leader: Brendan Daly, MD Recorded CPR time: 5 minutes Type of arrest: VF/VT Minute Chest Compression

Fraction (goal >90%)

Average Compression Rate (goal 100)

Average Compression

Depth (inches) (goal 2-4 inches)

1 100% 118 3.02 2 73% 107 2.98 3 82% 115 3.10 4 85% 121 2.85 5

Defibrillations: 1 Pre-shock pause (goal <3 seconds) 14 seconds Post-shock pause (goal < 6 seconds) 3 seconds Use of End Tidal Carbon Dioxide: Yes Other comments: Good compression rate and depth, great use of EtCO2. Summary: (selected strips below)

Defibrillation:

Results• Chest compression fraction 91%

• Compression rate 123/min

• Compression depth 2.6 inches

• Pre-shock pause 2.6 sec

• Post-shock pause 3.6 sec

• Perfusion check 4.3 sec

• Ventilation rate 9.7/min

• PetCO2 15.3 mmHg

What if we’re wrong?

2. Controlled ventilation

Kern (2002) Circulation

Prime the Pump!

Continuous Chest Compressions with Synchronous Ventilations (10:1)

3. Pressor Therapy

Pressors

Mader (2008) Resuscitation

Hagihara (2012) JAMA

*

*

*

Vasopressin?

Fluids?

4. PetCO2 in resuscitation

Lung Perfusion in ShockPaCO2

40 mmHgPaCO2

40 mmHg

PetCO237 mmHgPetCO2

37 mmHgPetCO2

29 mmHgPetCO2

29 mmHgPetCO2

21 mmHgPetCO2

21 mmHg

PetCO2 MonitoringPetCO2 Monitoring

PetCO2 Associations

• Initial PetCO2 α ROSC

• Pre-shock PetCO2 α ROSC for VF

• Rise in PetCO2 α ROSC

• Initial PetCO2 α arrest etiology

• Compression depth/patient wt α PetCO2

5. Post-resuscitation care

Hyperventilation: Three Flavors

Cerebral Perfusion During Shock

0

5

10

15

20

25

30

35

40

45

RR6 RR12 ETCO2

P = .004 v 12P = .004 v 12

mL/100 gm/min

Ventilation in Resuscitation

Rapid, Shallow Breaths?95% CI for the regression estimate

0 20 40 60 800

500

1000

1500

Est TV

VR

95% CI for the regression estimate

0 20 40 60 800

500

1000

1500

Est TV

VR

Intrathoracic Pressure

Evidence for Hypothermia?

Hypothermia After Cardiac Arrest Study Group (2002) NEJM

Hypothermia vs. Normothermia?

When should we cool?

no cooling

33oC

0 10 20 30 40 50 60 % survival

36%

53%

no cooling

33oC

26%

49%

36oC

33oC

52%

50%

Post-Arrest Hypothermia HACA

Bernard

TTM

How should we cool?

How should we cool?

Current U.S. Benchmark

Conclusions

• The opportunity is staggering

• Compressions

• Technology

• Post-resuscitative care