Renal Heart Failure Overview and Practice Questions

Renal Heart Failure: Heart vs Kidney [Explained]

by | Updated: Jan 28, 2023

We often think of the heart and kidneys as two completely separate organs, but in reality, they’re closely linked. Heart failure can lead to kidney failure, and vice versa. So, what is renal heart failure? What is heart failure?

That is exactly what we are going to explore in this article. Keep reading to learn more about the relationship between these two important organs!

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What is Renal Failure?

Renal failure occurs when kidneys stop working or aren’t functioning as they should. There are several causes of kidney failure, including the following:

  • Lack of blood flow to the kidneys
  • High blood pressure
  • Diabetes
  • Glomerulonephritis
  • Polycystic kidney disease
  • Kidney stones

There are two types of kidney failure: acute and chronic. Acute renal failure occurs suddenly, while chronic renal failure develops over time.

What is Heart Failure?

Heart failure is a condition in which the heart can’t pump enough blood to meet the body’s needs. There are many causes of heart failure, including the following:

Each type of heart failure has different symptoms, but some common signs and symptoms of heart failure include shortness of breath, pedal edema, fatigue, and tachycardia.

The Relationship Between that Heart and Kidneys

Now that we know a little bit about heart failure and kidney failure, let’s take a closer look at the relationship between these two conditions.

As we mentioned before, heart failure can lead to kidney failure. This is because when the heart isn’t pumping properly, blood flow to the kidneys is decreased. This can cause the kidneys to work less efficiently and eventually lead to renal failure.

Kidney failure can also lead to heart failure. This is because when the kidneys aren’t working properly, they can’t remove excess fluid and waste from the body. This fluid buildup can put a strain on the heart and eventually lead to heart failure.

It’s important to remember that heart failure and kidney failure are two separate conditions. However, they are closely linked and can cause a downward spiral if one condition is left untreated.

Renal Failure Practice Questions:

1. What is renal failure?
The inability to maintain fluid, electrolytes, and acid-base balance, excrete waste products, maintain metabolic functions

2. What is acute renal failure?
It is a decrease in creatinine clearance over several days which often has symptoms and many causes.

3. What is chronic renal failure?
It is chronic kidney disease. It is slow, steady deterioration of renal functions that is usually due to diabetes or hypertension. You will only see symptoms in severe stages.

4. What is the composition of the blood largely determined by?
It is determined by what the kidneys retain and excrete.

5. How do you treat chronic renal failure?
You should treat the symptoms with dialysis and antihypertensives.

6. What is dialysis?
It is a procedure for filtering the blood in place of kidney function. It also maintains fluid status, pH and remove nitrogenous waste.

7. What is hemodialysis?
Blood goes through a dialyzer which is a semipermeable membrane filter.

8. What is the function of the kidneys?
It filters dissolved particles from the blood. It also selectively reabsorbs substances needed to maintain normal composition of body fluids. It is where urine is formed.

9. What are the cardiopulmonary problems when the kidneys fail?
Hypertension, CHF, pulmonary edema, anemia, and pH changes.

10. What are nephrons?
They are the functional units of the kidneys. Each kidney has 1 million nephrons. It consists of glomerulus, proximal convoluted tubule, loop of Henle, and distal convoluted tubule. It is where urine is formed.

11. What are the 3 things involved in urine formation?
Glomerular filtration, tubular reabsorption, and tubular secretion.

12. What is glomerular filtration?
Water and dissolved substances (electrolytes) forced out of glomerular capillaries into Bowman’s capsule. The rate of filtration (GFR) is directly proportional to hydrostatic pressure of the blood. About 125 mL of fluid/min is filtered (but only 1 mL/min is excreted).

13. What is the glomerular filtration rate?
The rate at which water and dissolved substances (electrolytes) are forced out of the glomerular capillaries into the Bowman’s capsule. This rate is directly proportional to hydrostatic pressure of the blood. The normal rate is 125 mL/min. GFR is the best overall index of kidney function. Normal GFR varies according to age, sex, and body size, and declines with age. The National Kidney Foundation recommends using the CKD-EPI Creatinine Equation (2009) to estimate GFR.

14. Why are there 2 sets of arterioles in the blood flow of the kidneys?
There are 2 sets of arterioles in the kidney blood flow (the afferent arterioles and efferent arterioles) because arterioles help regulate blood pressure in the glomerulus so that it is just right for glomerular filtration. Arterioles are resistance vessels. They can vasodilate or vasoconstrict to adjust blood pressure. The rate of filtration is directly proportional to the hydrostatic pressure of the blood.

15. What are the 2 ways the kidneys can concentrate or dilute urine?
Countercurrent mechanism and selective permeability.

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16. What ions that the kidneys help to regulate?
Sodium, potassium, calcium, magnesium, and phosphate.

17. What is the kidney?
They filter dissolved particles from the blood and resorb the substances needed. It is the 2 bean-shaped organs in posterior wall of abdominal cavity. They are 12 cm long x 6 cm wide (5 in long x 2 1/2 in wide).

18. What is the hilum?
Medially, in the central concave portion of each part of the kidney. It has a longitudinal fissure. The renal artery, renal vein, and nerves enter and leave kidneys through the hilum.

19. What are the ureters?
Transport urine from the kidney to the bladder, also exist the kidneys through the hilum.

20. What is the cortex?
The outer one-third of the kidney is a dark brownish red layer.

21. What is the medulla?
Middle two-third of the kidney and be a light-colored layer.

22. How is blood supplied to the kidneys?
From right and left renal arteries are main blood supply to kidneys. It enters through hilum of kidney.

23. What are the collecting ducts?
A functional part of the nephron because of their role in urine concentration, ion salvaging, and acid-base balance.

24. What is glomerular filtration?
Water and dissolved substances (i.e. electrolytes) are forced out of the glomerular capillaries by blood pressure (hydrostatic pressure). Rate of filtration is directly proportional to the hydrostatic pressure of blood.

25. What is tubular reabsorption?
Glomerular filtrate passes through proximal through convoluted tubule, loop of Henle, and distal convoluted tubule. Water, sodium, glucose and other substances enter blood.

26. What is tubular secretion?
Various substances are transported from plasma to renal tubule. Substances transported include hydrogen ion H+ and K+.

27. What is sodium?
It is controlled by the regulating of water in the body.

28. What happens when there is low potassium?
causes muscle weakness, diarrhea, metabolic alkalosis, cardiac arrhythmias

29. What happens when there is high potassium?
It causes muscle weakness, metabolic acidosis, and life-threatening arrhythmias. High potassium corrected by excreting more.

30. What is the regulation of acid-base?
Extracellular fluids to acidic and kidneys excrete hydrogen ions. Also, fluid too alkaline which kidney excrete bicarbonate.

31. What is the correlation between mechanical ventilation and renal failure?
Increased pressure during mechanical ventilation decrease venous return to heart, pressure and blood volume in atria decreased, trigger more ADH to be released, and amount of urine produced decreases.

32. What is the Bowman’s capsule?
It collects filtrate from glomerulus.

33. What is the glomerulus?
It squeezes fluid (water, glucose, salts, and urea) out of blood into Bowman’s Capsule.

34. What is the proximal convoluted tubule?
Osmoregulation where most of the glomerular filtrate is reabsorbed.

35. What is the Loop of Henle?
It concentrates the filtrate and allows diffusion of salts and water back into blood.

36. What is the distal convoluted tubule?
It filters out sodium, potassium, and calcium.

37. What is the collecting duct?
It collects urine to be excreted.

38. What is the renal artery?
Blood vessel that carries blood to the kidney.

39. What is the renal vein?
Blood vessel that carries blood away from the kidney and toward the heart.

40. What is the renal pelvis?
Collection site for urine before it exits kidney.

41. What is the afferent arteriole?
It carries blood toward glomerulus.

42. What is the efferent arteriole?
It carries blood out of glomerulus.

43. What is the renal cortex?
It is the outer layer of kidney.

44. What is the renal medulla?
The whole inner portion of kidney.

45. What is osmolarity?
Concentration of potential osmotically active atoms.

46. What is permeable to the descending limb of the loop of Henle?
Water as osmolarity pulls water out.

47. What is permeable to the ascending limb of the loop of Henle?
Na+ as electrochemical gradient pulls sodium out.

48. Where is ADH released?
Posterior pituitary.

49. How does ADH work?
Changes the permeability of the later distal tubule, collecting duct and the medullary collecting duct. Aquaporin permeability in CD and LDT. And urea transport in medullary CD.

50. What happens when ADH is low?
The collecting duct is impermeable to water, so water must be excreted, and high-volume dilute urine is produced.

51. What happens when ADH is high?
The distal tubule and collecting duct are made permeable to water and urea.

52. What is the function of aldosterone?
It causes the kidney to conserve sodium and water.

53. What does it mean if there is an increase in sodium and water?
Increase in blood volume.

54. What do you call the increase in sodium and water along with hormones and everything else?
Renin-angiotensin-aldosterone system (RAAS).

55. In what is the RAAS important in the management of?
Heart failure

56. What is the effect of the increased sympathetic activity and presence of angiotensin II?
It causes pituitary gland to release anti-diuretic hormone.

57. What is the function of ADH?
It causes kidney to conserve water, increasing blood volume and vasoconstriction.

58. What governs blood flow to tissue?
Intrinsic factors.

59. What governs arterial blood pressure?
Extrinsic mechanisms.

60. Give some examples of intrinsic controls?
Metabolic control and paracrine control.

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61. What is active hyperemia?
The increase in organ blood flow that is associated with increased metabolic activity of a tissue or organ.

62. What also increases if the metabolic rate in a tissue?
O2 consumption, production of waste product, and potassium outflow.

63. What does oxygen do to blood vessels in systemic circulation?

64. What happens to the diameter of blood vessels when there is decreased oxygen?
Increases = vasodilation.

65. What is the effect of vasodilation of blood vessels within systemic circulation due to decreased oxygen?
Increases blood supply to the area.

66. What is the effect of vasodilation of the arterioles?
Opening of more capillaries.

67. What breathing pattern is present during renal failure?
Kussmaul breathing.

68. What breath sounds are present during renal failure?
Crackles are likely, especially if the patient also has CHF.

69. What is the expected fluid output for someone with renal failure?
Less than 500 mL per day.

70. Which blood test is helpful in diagnosing renal failure?
Creatinine levels.

Final Thoughts

In conclusion, renal heart failure is a term that describes the relationship between heart failure and kidney failure. These two conditions are closely linked, and each can lead to the other. This is why it’s important to develop an understanding of both systems and how they’re closely related. 

We have similar guides on the cardiovascular system and congestive heart failure (CHF) if you want to expand your knowledge further on this topic. Thanks for reading!

Written by:

John Landry, BS, RRT

John Landry is a registered respiratory therapist from Memphis, TN, and has a bachelor's degree in kinesiology. He enjoys using evidence-based research to help others breathe easier and live a healthier life.


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