Cardiogenic Shock

What is cardiogenic shock

the result of the heart's failure to pump blood forward effectively

Most common cause of cardiogenic shock

Acute MI; about 15%

Other causes of cardiogenic shock

ventricular ischemia, structural problems, dysrhythmias

Cardiogenic shock falls under this classification of post MI heart failure and is diagnosed with this specific criteria

Class IV heart failure; >40% necrosis of the left ventricle

Initial s/s related to decreased CO

SBP <90 mm Hg; restlessness, anxiety, lethargy, confusion, decrease sensorium, cool, pale, moist skin, UO<30cc, angina

Left ventricular failure symptoms

breath sounds have crackles (fluid), rhonchi (mucus-hear when coughing b/c moves mucus); S3 & S4 heart sounds

Right ventricular failure s/s

JVD, peripheral or dependent edema, hepatomegaly, splenomegaly, wt gain

Hemodynamically this would decrease in cardiogenic shock

CO and Cardiac index

Hemodynamically this would increase in cardiogenic shock

CVP, PCWP, SVR

Cardiogenic shock pts responding well to drug therapy when these goals are met

improved tissue perfusion, decrease cardiac workload and increase contractility

Med used to increase renal perfusion, but this is the unwanted SE

dopamine at 2-5mcg/kg/min; tachycardia

Levophed

drug improves BP but also increases afterload which leads to loss of a limb or digit

NTG

drug ordered with levophed to counteract vasoconstriction but it can cause a decrease in BP

Vasopressors and positive inotropes

drugs used to maintain organ perfusion but also end up increasing myocardial oxygen demand and can worsen ischemia

When the cardiogenic shock pt does not respond to drug therapy, this may be inserted

Intra-aortic balloon pump (IABP)- which is an intra-aortic counter pulsation device or a blood volume displacement device)

Coronary perfusion via these arteries occurs during this phase of the cardiac cycle

coronary arteries (which originate just above the cusps of the aortic valve of the heart) and diastole

Coronary artery flow is decreased during this phase of the cardiac cycle because of this reason

Systole- during contraction, heart muscles compress the coronary capillaries creating an increase in coronary vascular resistance

IABP provides assistance to...

the left ventricle

The IABP can be inserted in these places in the hospital

OR, cath lab or ICU at pt's bedside

The balloon is positioned in this area of the body

in the descending thoracic aorta just distal to the take off of the left subclavian artery

The balloon is inflated during this and does this to the blood

inflated during the diastole (which is like the heart having an extra systole); the blood in the aorta is displaced back toward the heart and forward to the systemic circulation

When the balloon inflates the position of the aortic valve is this and the blood is forced into this area of the heart

aortic valves are closed and the blood is forced into the coronary arteries

Blood volume in the aorta below the level of the balloon will be propelled this way which may improve circulation to this...

forward and kidneys

The balloon is deflated during this...and creates this type of effect

deflated just before systole of the cardiac cycle and creates a vacuum effect

Benefits when balloon deflates

decreases afterload, facilitates ventricular emptying and reduces myocardial O2 demand

This is essential for the IABP to work properly and can be synchronized according to...

timing is essential; synchronized according to EKG or arterial blood pressure tracing

This can adversely affect the timing of the balloon inflation and deflation

dysrrhythmias

hemodynamically these parameters will decrease b/c of IABP

CVP, PCWP, SVR

hemodynamically these parameters will increase b/c of IABP

CO and MAP

Assessments for legs for IABP

pulsesness (DP, PT quality & presence), pallor (color), temp, cap refill, paralysis (motor fxn), paresthesia (sensory fxn)

Due to possible migration of the balloon this should be assessed

left radial pulse and UO

Activities and positioning for IABP

avoid flexing leg, move by logrolling from side to side, HOB should be flat

This lab value should be monitored closely for an IABP pt

platelets b/c thrombocytopenia may occur b/c mechanical destruction of platelets by the pumping action of the balloon

What does RVAD and LVAD stand for

Right or left ventricular assist device

VADS are inserted b/c of this reason

when pts need circulatory support until heart transplantation can be performed

VADs should not be implanted unless pt has someone at home that can do these 2 things

recharge the battery every few hours and resuscitate the pt in the event of an emergency

Heart transplantation is generally not performed in pts with these conditions

over 65-70 y/o, other medical conditions are expected to limit their lifespan, pts who cannot be counted on to comply with the demanding medical regimen