In: Nursing
Mr. Vincent is a 45-year old salesman; he is overweight and has a sedentary lifestyle. At work he suddenly develops severe chest pain and is nauseous. A coworker takes him to the nearby hospital. The ER doctor orders an immediate EKG. A diagnosis of acute myocardial infarct (MI) is made and Mr. Vincent is scheduled for a balloon angioplasty. The following day the surgery is done, and Mr. Vincent recovers with no complications. Tom, the nurse clinician, is assigned to educate Mr. Vincent regarding his procedure and the follow-up medications.
1) If Mr. Vincent’s stroke volume is decreased how would his heart compensate for the decrease thus “trying” to maintain the cardiac output? Please describe the mechanism of the compensation.
Below are two types of medications the physician could prescribe for Mr. Vincent. Please explain why these drugs could be useful to Mr. Vincent.
When the heart muscle doesn't able pumb as much blood as bodybneeds.Because of heart cannot able to pump well,them heart and body try to maintain cardiac output , it is called compensation.
Heart and body has remarkable ability to compensate low stroke volume.But peoples doesn't feel its in early stages .because heart itself do that job.But later when heart weak from the over work , and not able to compensate peoples can begin to experience symptoms.
How does the heart compensate.
To maintain cardiac output, heart will start to beat more faster and pump more blood in each beat.it helps to increase stroke volume. When cardiac output is low brain signals the heart to beat faster by sending messages to your heart’s electrical system. Which controls the timing of your heartbeat.same time adrenal gland also release more epinephrine, it stimulate the heart to beat faster.
When the stroke volume is less ,left ventricle is not pumping blood out well,then the heart try to compensate this by allowing more blood to fill the ventricle before it pump by expanding size to increase volume. it helpful at first , but it increases the strain on the heart making its function worse over time. Also heart can pump harder devoleping thicker muscle. This thickening is called hypertrophy.it can help your heart to pump more forcefully and increase your stroke volume.
***ANTI PLATELET DRUG **Example: Aspirin
it is used to inhibit the platelet aggregation and is used in the prevention of blood clots ,stroke,and myocardial infraction.
Acetyl salicylic acid blocks prostoglandin synthesis. It is nonselective for COX-1and COX-2 enzymes inhibition of COX-1 results in the inhibition of platelet aggregation for about 7- 10 days .The acetyl group of acetyl salicylic acid binds with serine residue of the cylooxygenase - 1 enzyme leading to irreversible inhibition. This prevents pain causing prostaglandings.this process stops the conversion of arachidonic acid to thromboxone A2 ,which is potent inducer of platelet aggregation..
***BETABLOCKER** example Atenolol.
Beata blockers are used to decrease heart rate.
cardioselectivevbeta 1 adrenetgic receptors found in vascular smooth muscle and the heart ,blocking the positive intropic and chronotropic actions of endogenous catacholemines such as iso proterenol,norepinephrine,and epinephrine thereby inhibiting sympathetic stimulation.this activity results in a reduction in heart rate blood pressure and decrease myocardial contractility.