I need answers of all the Five Questions from the case study below, Thanks CASE

Question

I need answers of all the Five Questions from the case study below, Thanks

CASE STUDY #3:

Chief Complaint: 68-year-old man with breathing problems.

History: A 68-year-old man with chronic renal failure was in the hospital in serious condition recovering from a heart attack. He had just undergone "balloon angioplasty" to re-dilate his left coronary artery, and was thus on an "NPO" diet (i.e. he was not allowed to have food or drink by mouth). He received fluid through an intravenous (IV) line. Late one night, a weary nurse who was on the 11th hour of a 12-hour shift came into the patient's room to replace the man's empty IV bag with a new one. Misreading the physician's orders, he hooked up a fresh bag of IV fluid that was "twice-normal" saline rather than "half-normal" saline (in other words, the patient starting receiving a fluid that was four times saltier than it should have been). This mistake was not noticed until the following morning. At that time, the man had marked pitting edema around the sacral region and had inspiratory rales ("wet-sounding crackles") at the bases of the lungs on each side. He complained that it was difficult to breathe as well. Blood was drawn, revealing the following:

Na+ 157 mEq / liter (Normal = 136-145 mEq / liter)

K+    4.7 mEq / liter (Normal = 3.5-5.0 mEq / liter)

C1- 101 mEq / liter (Normal = 96-106 mEq / liter).

A chest x-ray revealed interstitial edema in the lungs. Most dissolved substances in the blood plasma can easily move out of the bloodstream and into the interstitial fluid surrounding the cells.

QUESTIONS: (5 questions - 6.67 points each):

1. Will the nurse's mistake increase or decrease the "saltiness" of the interstitial fluid? Given your knowledge of osmosis, will this cause the cells in the body to increase or decrease in size?

2. Why does this patient have pitting edema and inspiratory rales?

3. How would this increase in salt load affect the patient's blood-aldosterone level? In your answer, explain the function of the hormone aldosterone. Can you think of any other normal mechanisms that the body has to control salt and water balance? How might they react in this situation?

4. What symptoms might result from hypernatremia ("high blood-sodium" level)?

5. How is this patient's interstitial edema in the lungs affected by his already-weakened heart?

Explanation / Answer

1.The intravenous fluid given to this patient was too concentrated with sodium and chloride. Because these ions diffuse freely between the plasma and the interstitial fluid, increase in plasma sodium and chloride concentrations will cause increase in interstitial fluid sodium and chloride concentrations.

2.Introducing hypertonic saline into this patient made the plasma and interstitial fluid sodium concentrations rise. As the plasma sodium level rises, more water than normal is passively, osmotically drawn from the renal tubules into the peritubular capillaries of the kidneys. This raises blood volume and blood pressure, causing a shift of water from the plasma into the interstitial spaces. Thus, the patient develops edema (i.e. swelling) in tissues.

This process is exacerbated by the patient's underlying chronic renal failure and heart attack. His failing kidneys have a difficult time excreting the excess sodium and chloride ions introduced into his body. Furthermore, his recent heart attack places him at increased risk of developing congestive heart failure. His left coronary artery blockage probably caused damage to his left ventricle. The osmotic increase in blood volume places an increased pre-load work requirement on an already impaired left ventricle. If this ventricle cannot pump blood out into the aorta at a rate equal to that of blood entering the left ventricle from the left atrium, hydrostatic pressure will rise in the left ventricle, left atrium, and ultimately the pulmonary circulation "upstream." An increase in pulmonary capillary hydrostatic pressure will force more water to be filtered from the bloodstream into the interstitial spaces of the lung tissue. As fluid builds up in these spaces, it may begin to collect in the alveolar air spaces and terminal bronchioles (a condition called "pulmonary edema"). If this happens, rales (i.e. crackling sounds) may be heard with a stethoscope when the patient inhales. These are the sounds of obstructed airways "popping open."

3.The function of aldosterone is to increase the tubular reabsorption of Na+ ions from the distal renal tubules into the bloodstream in exchange for the tubular secretion of K+ and/or H+ ions from the bloodstream into the distal renal tubules. It probably does this indirectly by stimulating the production of the requisite transport protein in the distal renal tubular cells. Thus, aldosterone helps the body correct hyponatremia (i.e. a lower-than-normal blood Na+ level) and hyperkalemia (i.e. a higher-than-normal blood K+ level). Furthermore, aldosterone helps increase the blood volume because water in the renal tubular fluid follows the Na+ ions by osmosis into the bloodstream. Hence, aldosterone helps the body maintain an adequate blood pressure.

There are several physiologic factors that stimulate the release of aldosterone from the adrenal cortex, the most important of which are (1) elevated blood-K+ level, (2) decreased blood-Na+ level, (3) decreased blood pressure (via stimulation of the renin-angiotensin-aldosterone axis), and (4) increased secretion of adrenocorticotropic hormone (ACTH) from the anterior pituitary gland. The opposite of each of these conditions decreases the release of aldosterone. In our patient's case, the elevated blood-Na+ level will inhibit release of aldosterone, and thus enhance the excretion of the excess Na+ions into the urine.

4.Osmotic shrinkage of cells during hypernatremia can cause shrinking of the brain and concomitant central nervous system symptoms such as lethargy, confusion, coma, convulsions, and respiratory paralysis. Muscular tremor, rigidity, and hyperreflexia may also occur.

5.This process is exacerbated by the patient's underlying chronic renal failure and heart attack. His failing kidneys have a difficult time excreting the excess sodium and chloride ions introduced into his body. Furthermore, his recent heart attack places him at increased risk of developing congestive heart failure. His left coronary artery blockage probably caused damage to his left ventricle. The osmotic increase in blood volume places an increased pre-load work requirement on an already impaired left ventricle. If this ventricle cannot pump blood out into the aorta at a rate equal to that of blood entering the left ventricle from the left atrium, hydrostatic pressure will rise in the left ventricle, left atrium, and ultimately the pulmonary circulation "upstream." An increase in pulmonary capillary hydrostatic pressure will force more water to be filtered from the bloodstream into the interstitial spaces of the lung tissue. As fluid builds up in these spaces, it may begin to collect in the alveolar air spaces and terminal bronchioles (a condition called "pulmonary edema"). If this happens, rales (i.e. crackling sounds) may be heard with a stethoscope when the patient inhales. These are the sounds of obstructed airways "popping open."

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