Question

1. What is hemodynamic monitoring and why is it needed?
2. Noninvasive versus Invasive monitoring?
3. Define pre-load( what is a pre-load reducer and increaser?) CVP=RAP
4. Define what is after load? Patients who have too much afterload and treatment? Do we want to decrease resistance and what type of patients? SVR(invasive hemodynamic monitoring)
5. What is cardiac output? When do we need to increase/decrease it? Normal CO is what and how do we get that number ( what is stroke volume?). What is cardiac index and normal value?
6. What is MAP and the normal value?
7. What is contractility? Positive or negative inotrope? Give examples and explain their purpose.
8. Pulmonary Artery wedge pressure( Swan Ganz Catheter or pulmonary artery catheter). Normal measure and types of clients we would use this with. Left or right side of the heart measuring?

Answer 1

(a) Hemodynamic monitoring measures the blood pressure inside the veins , heart and arteries .It also measures blood flow and how much oxygen is in the blood . It is done to know how well the heart is working .Hemodynamic monitoring can detect these changes early by testing samples of blood from deep inside the body .

(b) Invasive monitoring procedures requires insertion of sensor or collection device into the body .

whereas Noninvasive monitoring procedures means of gathering data externally

Generally , invasive procedures provides more accurate data but carry greater risk .

After gradient between invasive and noninvasive method is established , trends in change of noninvasive method can be useful in making clinical decision .

NON- INVASIVE	INVASIVE
well accepted , evidence based and recommended treatments Pressure / compression therapy Silicone sheets and gels Investigational treatments and those with less supporting evidence oils , loation ,creams , massage therapy ,   static and dynamic splints	Intralesional corticosteriods injection Surgical scar correction Laser therapy Radiosurgery cryosurgery Intralesional injection

(c) In the cardiac physiology , preload is the amount of sarcomere stretch experienced by cardiac muscle cells called cardiomycocytes , at the end of ventricular filing during diastole . Preload is directly related to ventricular filling .

Preload - reducer ;- Reduced pulmonary venous return that decrease pulmonary capillary hydrostatic pressure and reduces fluid transduction into pulmonary interstitum and avoli .

Preload increaser ;- when venous return to the heart is increased , then the end - diastolic pressure and volume of the ventricles are increased , which stretches the sarcomeres , thereby increasing their preload .

Central veneou s pressure ( CVP) is the blood pressure in the venae cavae , near the  right atrium of the heart . CVP is often good approximation of right atrial pressure (RAP) , although the two terms are not identical as a pressure differential can sometimes exist between the venae cavae and the right atrium .

(d) After load is the pressure that the heart must work against to eject blood during systole .Afterload is proportional to the average arterial pressure .As aortic and pulmonary pressures increase , the afterload increase on the left and right ventricles respectively .

The afterload increase in thepatient suferred from cardiac failure , left ventricular hypertrophy , and in mechanically ventilated cardiac surgery patient who have stiff aortas and dilated ventricles . cardiac valve stenosis patient . airtic valve stenosis patient ,

Nitropruside is a potent , and direct smooth muscle relaxing agent that primarily reduces afterload but can midly reduce preload . It improves cardiac output but can precipitiously decrease blood pressure . Intra- arterila blood pressure monitoring is strongly recommended.

(e) cardiac potput is also known as heart output denoted by the symbols or is a term used in cardiac physiology that describes the volume of blood being pumped by the heart , by the left and right ventricle , per unit time .

During the excercise , our body may need 3-4 times from normal ,cardiac output because our muscle need more oxygen when we exert ourself , During excersie , our heart typically beats faster so that more blood gets out to our body .

Condition like myocardial infarction , hypertension , valvular heart disease , congenital heart disease , cardiomyopathy , heart failure , pulmonary disease , arrythmias , drug effects , fluid overload , decrease fluid voulme and electrolyte imbalance are considered the common cause of decreased cardiac output .

A healthy heart with a normal cardiac output pumps about 5-6 liter s of blood every minute when a person is resting .

In cardiovascular physiology , stroke volume(SV) is the volume of blood pumped from the left ventricle per beat .

SV = EDV - ESV

SV= stroke volume

EDV= end diastolic volume

ESV= end systolic volume

And cardiac volume is the product of the heart rate (HR) and the stroke volume (SV)

thus, CO = HR x SV (L/ min)

cardiac index is a hemodynamic parameters that relates the cardiac output (CO ) from left ventricle in one minutes to body surface area (BSA ) . Thus relating heart performance to the size of the individual .The unit of measurement is litres per minute per square metre ( L / min/ m2 ) . it s normal range is 2.5 - 4.0 l/min/ m2

(f) The definition of mean arterial pressure is the average arterial pressure throughout one cardiac cycle , systole and diastole. It is influenced by cardiac output and systemic vascular resistance . ITs normal range is 70 - 100 mmHg .

(g) contractility is the inherent strength and vigour of the heart 's contraction during systole , According to the Starling law , the heart will eject a greater stroke volume at greater filling pressures . For any filling pressures , the stroke volume will be greater if the contractility of the heart is greater .

An inotrope is an agent that alters the force or energy of muscular contractions . Positively inotropic agent increase the strength of muscular contraction (  for example ;- digoxin , calcium, dopamine , dobutamine , adrenaline prostaglandin)   . and the negatively inotropic agent weaken the force of muscular contractions. ( for example ;- Diltiazem , verapamil, quinidine , beta blocker)

(h) the pulmonary wedge pressure is also known as sectional pressure , it is pressure measured by wedging a pulmonary catheter with an inflated balloon into a small pulmonary arterial branch ,It estimates the left arterial pressure .  pulmonary capillary wedge pressure provides an indirect estimate of left artrial pressure ,Although left ventricular pressure can be directly measured by placing a catheter within the left ventricle , it is not feasible to advances this catheter back into the left atrium . The normal pulmonary capillary wedge pressure is between 4-12 mmHg.

THE pulmonary capillary wedge pressure is measured by inserting balloon tipped multi lumen catheter ( swan - ganz- catheter ) into aperipheral vein ( e.g - jugular vein or femoral vein) then advancing the catheter into the right artrium , right ventricle , pulmonary artery and then into a branch of the pulmonary artery The catheter determine bt viewing the pressure measured from the tip of the catheter In the right atrium , the pressure usually fluctuates <5mmHg and fluctuates a few mmHg . The pressure recorded during ballon inflation is similar to left atrial pressure because the occluded vessel and it s distal branches that eventually from the pulmonary vein act as a long catheter that measures the blood pressures within the pulmonary veins and left atrium.

we will we usually used in hypertension patient , in this patient capillary wedge pressure exceeding 25mmHg .