Need help with cardiac asap!!!

Muffy5 · Jun 10, 2010

Always remember MONA with AMI. Morphine to decrease anxiety and HR, but also to vasodilate and decrease preload to the heart, therefore decreasing the level of work it has to do. Oxygen to increase O2 concentration to the dying heart muscle Nitroglycerin again to decrease preload, and to rule out Angina in those that MI have not been diagnosed and Aspirin to act as an anticoagulant and dissolve the clot. The patient should also be put into a high fowlers position to decrease preload and cardiac workload. Epinephrine may be given to increase cardiac output. I hope that helps...that's all I can remember at the moment.

turnforthenurse, MSN, NP · Jun 11, 2010

I am working on a case study and I have worked on this for a long time, but still can't get very far. I also have a test coming up on this material and I am not processing the information very well....
Patient who had MI in the critical care unit has following measurements showing on monitoring system:
HR 133
BP 88/49
MAP 62
Right atrial pressure 7
CO 3.2
CI 1.2
PAWP 25
The assignment is to outline hemodynamic concerns based on these measurements, and to include any anticipated interventions, drugs, etc.
Obviously the BP is down and fluid level would be low, and the patient is tachy trying to compensate. CO is decreased, and MAP is low. This is about as far as I get!

First off I would recommend interpreting your hemodynamic values:

*HR 133 - tachy

*BP 88/49 -

*MAP 62 - perfusion is bad. I know values vary, but I learned that MAP should be between 70-105mmHg for adequate perfusion to organs.

* RAP 7 - values vary, but I was taught to know 2-8mmHg as the norm. Remember RAP measures right preload, very similar to CVP (2-6mmHg)

* CO 3.2 - below normal. should be 4-8L/min. Low due to the MI.

* CI 1.2 - remember, CI is a better indicator than CO if available. Normal CI should be 2.2-4L/min (from what I was taught to know). a CI of 1.8 or less is considered frank cardiogenic shock.

* PAWP 28 - PAWP measures left preload, and the norm is 6-12mmHg. This is elevated. Depending on the area of infarct, this could indicate left ventricular failure. Your left ventricle is the chamber that pumps blood to systemic circulation and if it isn't working properly, that means your CO/CI will fall and you also have a drop in BP because of that.

Now consider cardiogenic shock:

* HR: increased d/t sympathetic stimulation

* Preload: increased (RAP is normal but your PAWP is elevated!)

* CO/CI: LOW

* Afterload: increased d/t sympathetic stimulation

* SvO2: low in cardiogenic (but will be low anyway because the CO/CI are low!)

An MI can lead to heart failure or cardiogenic shock. Since the patient has had an MI, the MONA mnemonic that Muffy5 mentioned would be used for treatment. But you also need to consider interventions and treatment for cardiogenic shock.

* ABG's (hypoxemia and met acidosis are seen due to hypoperfusion on other organs)

* Lactic acid (>2 is bad!)

* Urinalysis - urine Na, osmolality and creatinine levels to reflect renal status

* Coag profile - Coag studies become progressively abnormal as shock state deteriorates as a result of capillary and/or endothelial dysfunction.

* Serum chem values - may see hypernatremia reflective of a water deficit or early renal insufficiency. Hyperkalemia may be seen with acute renal failure secondary to lack of perfusion during hypotension.

* Electrolyte imbalances can lead to dysrhythmias, so EKG monitoring may be done.

* Correct acidosis (NaHCO3- IVP guided by ABG's)

* Correct electrolyte imbalances (K+, Na+, Cl-, Mg++)

* If there is too much preload, use diuretics but don't cause them to be hypovolemic! You can also decrease preload with morphine and NTG.

* Use of + inotropes to improve contractility because you have decreased forward flow of blood and contractility is poor. Mid-dose dopamine can be used as a + inotrope (high-dose dopamine acts as a vasoconstrictor, increasing HR & SVR which increases the workload of the heart = bad!) Dopamine is the first-line inotropic agent in cardiogenic shock.

* May use vasopressors to increase BP & MAP (want to perfuse those kidneys!!!) such as norepi (Levophed) or epi or phenylephrine.

* Anticipate possible IABP, VAD (ventricular assist device), PTCA, CABG

* Thrombolytic therapy

Hope this helps :)