Cardiogenic Shock and heart failure

Anjel

Anjel

Forum Angel
Messages
4,548
Reaction score
302
Points
83
Ok people... Part One of my final is next week.

I'm having an issue understanding the principles, mechanisms, and treatment of cardiogenic shock.

Is cardiogenic shock strictly a pump problem? Caused by injury like contusion or tamponade?
Does it occur after infarction? Or is it after you rule out things like hypovolemia, dysrrythmias, or poor vascular tone? I'm confused.

Also left sided vs right sided heart failure. Is it possible to have right sided heart failure without left side involvement? As I understood, left sided heart failure causes right. Pulmonary edema will cause the pitting edema in the extremities. But can right side failure cause left?

If someone could just walk through this with me. I want to have a firm grasp on it before taking my final.
 
Ah one of my favorite topics. I am actually taking care of a IABP patient today. I will try to type out a detailed response tonight after work but I'm sure others will chime in before me.

The most common cause of cardiogenic shock is acute myocardial dysfunction related to STEMIs. The myocardium, specially the LV, is dead and/or stunned and not pumping a sufficient amount to meet the body's needs.
 
Anjel said:
Is cardiogenic shock strictly a pump problem?
Click to expand...

Yes. Though, of course it can be complicated (or caused) by other causes of shock.

Anjel said:
Caused by injury like contusion or tamponade?
Click to expand...

Potentially, but most commonly by AMI or a severe valvular problem.

Anything that keeps the heart from pumping adequately. Even a dysrythmia.


Anjel said:
Or is it after you rule out things like hypovolemia <snip> or poor vascular tone?
Click to expand...

Nope. Those are separate causes of shock. Though again, they can potentially coexist with cardiogenic shock.

Anjel said:
Is it possible to have right sided heart failure without left side involvement?
Click to expand...

Yes. Think about pulmonary htn, where the right side of the heart is stressed but the left side is relatively unaffected until the right sided function gets really bad.

However, cardiogenic shock generally implies left sided dysfunction.

Cardiogenic shock is generally managed by trying to improve myocardial function (such as with an inotrope) while also managing afterload and preload with pressors or dilators in order to maximize CO and reduce workload on the heart (i.e. avoiding things that increase myocardial oxygen demand, such as tachycardia and excessive afterload or preload).

I think it is helpful to think of the two sides of the heart as completely separate pumps that work together in series, therefore affecting each other's workload.
 
Ok thank you.

So pulmonary htn causes right side failure which in turn causes left? Which in turn causes pulmonary edema?

Just making sure I read that right.

Also, if cardiogenic shock is often caused by an AMI. Would it matter what type of MI? Say if they are having an inferior MI, would you expect to see right sided failure first?
 
Heart failure generally goes from the left side to right,and in this case,pulmonary htn refers to the pulmonary trunk and alveoli.This consequently raises pressure in the right ventricle,causing hypertrophy, dilatation,and failure.This can be caused acutely by a PE,or chronically by obstructive lung diseases(asthma,chronic bronchitis,emphysema,etc.)If the left side is normal, then it shouldn't fail because of the right side.

But because of decreased pulmonary venous flow to the left side,we can imagine it causes some hypoxia all over...

Look up cor pulmonale:)
 
You must log in or register to reply here.
Back
Top