ACLS in 2013The science behind the changesMichele Vicari-Christensen DNP ARNP

August 17th 2013

Objectives

1) Discuss the recent changes in ACLS2) Understand the scientific rationale

for the changes presented3) Explain the use of capnography and

hypothermia4) Explore the rationale for key pharmacological changes in the algorithms5) Illustrate the Chain of Survival

CPRCPR Quality-Concensus Statement Circulation June 2013

1) Must use a systematic approach to assess and treat arrest and acutely ill or injured patients for optimum care which includes:

-High quality CPR -Capnography -Hypothermia -Optimal glycemic control -Appropriate algorithms and pharmolcological

agents

2) Goal of any resuscitative action is return of spontaneous circulation (ROSC) and neurological preservation

Worldwide there are > 135 million cardiovascular death annually

Globally, the incidence of out of hospital cardiac arrest ranges from 20-140K/110K in the US

Survival ranges from 2-11% in the US

These statistics establish cardiac arrest as one of the most lethal public health problems in the US taking more lives than colorectal cancer, breast cancer, prostate cancer, influenza, pneumonia auto accidents HIV firearms and house fires combined

The American Heart Association (AHA) recommends focusing primarily on effective cardiac compressions during

resuscitative efforts

Importance of compressions-5 critical components

1) Minimize any interruptions in effective chest compressions.

2) Provide compressions of adequate rate and depth

3) Avoid leaning between compressions4) Allow complete chest recoil after each

compression5 Avoid excessive ventilation

CPR survival is dependent on adequate myocardial oxygen delivery and myocardial blood flow:

Chest compression fraction (CCF) of >80%-minimal interruptions

Chest compression rate of 100-120

Compression depth of 50 mm or 2 inches in adults (1/3 anterior, posterior dimension of chest

No Leaning causes lack of recoil

Excessive ventilation decreases depth and recoil

Push it to the limit

Monitoring the effects of CPR:

Cardiac perfusion pressure (CPP)of>20 mmHg-defined by arterial end diastolic pressure minus central venous pressure (CVP). Requires and

arterial line and a central line during CPR

Capnography-ET CO2 of > 20 mmHg

The AHA recommends the use of capnography

to monitor the effectiveness of chest

compressions during CPR in the intubated patient

CapnographyWhat is waveform capnography ?

Quantitative waveform capnography is the continuous, noninvasive measurement and graphical display of end-tidal carbon dioxide/ETCO2 (also called PetCO2).

Capnography uses a sample chamber/sensor placed for optimum evaluation of expired CO2. The inhaled and exhaled carbon dioxide is graphically displayed as a continuous waveform on the monitor along with its corresponding numerical measurement

CapnographyCirculation. Blood must be moving in order to deliver CO2 from the tissues to the alveoli. Circulation requires blood, an effective heartbeat and blood pressure. Preload plus afterload equals circulation. Mimic in compressions.

In the acute setting, PetCO2 is a function of cardiac output

Ventilation. Air must move in and out of the alveoli effectively to get rid of carbon dioxide and other waste products, and to inhale fresh oxygen.

Capnography1) Qualitative waveform capnography

(PETC02) provides a quality measure for CPR

2) Optimal goal for CPR is PETC02 of 35-40 mmHg equates to same as when ROSC

3) If PET Co2 is < 10 mmHg attempt to improve CPR-a PetC02 is 10 or less after initiation of ACLS is associated with poor outcomes.

The AHA recommends the use of hypothermia in the treatment of neurological injury post cardiac

arrest in the field from Pulseless Electrical Activity, Ventricular Fibrillation and Asystole

Hypothermia

The new guidelines recommend cooling comatose adult patients with ROSC after out of hospital VF, PEA and Asystole cardiac arrest to 32-34 degrees C (89-93 degrees F) for up to 12-24 hours

Moderate hypothermia used since 1950 to protect the brain from global ischemia-lowers cerebral metabolic rate for oxygen (CMRO2)

by 6% for every degree.

Reduces cerebral histological deficits associated with reperfusion injury :

-less mitochondrial damage, -decreased free radical production-less excitatory amino acid release

-less calcium shifts-less neural cell apoptosis

Methods:1) External cooling

blankets, ice , wet towels and fanning, cooling helmet2)Intravenous

30 cc/kg of crystalloid at 4 C over 30 minutes3) Peritoneal lavage

4) Pleural lavage5) ECMO

Side Effects and ComplicationsHigher Systemic Vascular Resistance,

PneumoniaLower Cardiac Index

HyperglycemiaCoagulopathy

ArrythmiasSkin Breakdown

The AHA recommends optimal glycemic control for neurological recovery post ACLS intervention.

Glycemic control

1)Target glycemic control 10 144-180 mg/dl in an adult patients after cardiac arrest and ROSC.

2)Avoid lower blood sugars in ranges of 80-110 mg/dl

Hyperglycemia causes cerebral microvascular changes and brain edema

that quickly lead to neuronal death

Hypoglycemia causes cerebral cellular fuel deprivation and cellular death as well as an increase in cerebral cellular

excitability and seizures.

The AHA recommends the appropriate algorithm with recommended

pharmacological agents

Sodium Bicarbonate

NAHC03

Henderson-Hasselbalch EquationRegulation of Carbonic Acid/Bicarbonate

buffer pair

Atropine

1) Parasympatholytic agent. Research

supports only effective utilization is in symptomatic bradycardia

2) There is no benefit in pulseless

electrical activity or asystole

The AHA recommends implementation of the Chain of Survival for ACS and CVA both in

the field and in the hospital

Chain of Survival

ACLS extends to Acute Coronary Syndrome and Cerebral Vascular

Accidents

In hospital survival from cardiac arrest is 20% from 7a-11p and declines to <

15% from 11p-7a

The majority of published data in the form of before and after

studies of Rapid Response teams have reported 17-65% drop in the rates of cardiac

arrest after teams were developed

ReferencesGuidelines for CPR and ECC (2010). AmericanHeart Association.

Field et al. (2010). Executive Summary- American Heart Association

Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiac Care. (2010). Circulation. November 2, 2010; pp. S640-S729.

CPR Quality-Improving Cardiac Resuscitation Outcomes Both inside and Outside the Hospital: A Concensus Statement from the American Heart Association. (2013).Circulation. June 25, 2013. pp. 1-19