Renal clearance

Examples of Renal clearance in the following topics:

• Renal Clearance

  • In renal physiology, clearance is a measurement of the renal excretion ability, which measures the amount of plasma from which a substance is removed from the body over an interval of time.
  • Renal clearance depends mainly on GFR, tubular absorption, and tubular secretion.
  • If any of those variables change, the renal clearance rate of a substance will change as well.
  • It is also important to note that renal clearance is not the only form of clearance that occurs for the substances within the plasma of the body.
  • Describe how clearance is a measure of the renal excretion ability

• Waste Management in Other Body Systems

  • Besides the renal system, many other organs and body systems are directly involved in the excretion of waste products.
  • Similar to renal clearance, these other organs have a clearance rate of their own, and also forms a part of total body clearance.
  • The skin, lungs, and liver are the main waste removal organs outside of the non-renal system; however, their ability to remove wastes is generally less than that of the renal system.

• Supply of Blood and Nerves to the Kidneys

  • The renal veins drain the kidney and the renal arteries supply blood to the kidney.
  • Due to the position of the aorta, the inferior vena cava, and the kidneys in the body, the right renal artery is normally longer than the left renal artery.
  • The renal arteries carry a large portion of the total blood flow to the kidneys—up to a third of the total cardiac output can pass through the renal arteries to be filtered by the kidneys.
  • Renal blood supply starts with the branching of the aorta into the renal arteries (which are each named based on the region of the kidney they pass through) and ends with the exiting of the renal veins to join the inferior vena cava.
  • The renal plexus are the source of nervous tissue innervation within the kidney, which surround and primarily alter the size of the arterioles within the renal cortex.

• Internal Anatomy of the Kidneys

  • The renal cortex is a space between the medulla and the outer capsule.
  • The kidneys are surrounded by a renal cortex, a layer of tissue that is also covered by renal fascia (connective tissue) and the renal capsule.
  • The renal cortex is granular tissue due to the presence of nephrons—the functional unit of the kidney—that are located deeper within the kidney, within the renal pyramids of the medulla.
  • The renal pelvis contains the hilium.
  • The renal pelvis connects the kidney to the rest of the body.

• Renal Disease and Failure

  • Renal failure uremia is a syndrome of renal failure characterized by elevated levels of urea and creatinine in the blood.
  • Renal failure (also kidney failure or renal insufficiency) is a medical condition in which the kidneys fail to adequately filter waste products from the blood.
  • Renal failure uremia is a syndrome of renal failure that includes elevated blood urea and creatinine levels.
  • Acute renal failure can be reversed if diagnosed early.
  • It is considered to be chronic renal failure if the decline of renal function is to less than 25%.

• Glucosuria

  • Rarely, glycosuria is due to an intrinsic problem with glucose reabsorption within the kidneys themselves, a condition termed renal glycosuria.
  • This point is called the renal threshold of glucose (RTG).
  • If the RTG is so low that even normal blood glucose levels produce the condition, it is referred to as renal glycosuria.
  • Renal glycosuria, also known as renal glucosuria, is a rare condition in which the simple sugar glucose is excreted in the urine despite normal or low blood glucose levels.
  • However, in those with renal glycosuria, glucose is abnormally elevated in the urine due to improper functioning of the renal tubules, which are the primary components of the nephrons that act as the filtering units of the kidneys.

• Overview of the Urinary System

  • The renal system organs include the kidneys, ureters, bladder, and urethra.
  • The  renal system has many functions.
  • The kidneys have an extensive blood supply from the renal arteries that leave the kidneys via the renal vein.
  • The nephrons are made up of a capsule capillaries (the glomerulus) and a small renal tube.
  • Urine passes from the renal tube through tubes called ureters and into the bladder.

• Renal Calculi

  • Renal calculi are kidney stones, or crystal aggregates of minerals which would normally be excreted in urine.
  • Ureteral obstruction causes postrenal azotemia and hydronephrosis (distension and dilation of the renal pelvis and calyces), as well as spasm of the ureter.
  • This leads to pain, most commonly felt in the flank (the area between the ribs and hip), lower abdomen, and groin (a condition called renal colic).
  • Renal colic can be associated with nausea, vomiting, fever, blood in the urine, pus in the urine, and painful urination.
  • Renal colic typically comes in waves lasting 20 to 60 minutes, beginning in the flank or lower back, and often radiating to the groin or genitals.

• Nephroptosis (Floating Kidney)

  • Nephroptosis, also called floating kidney or renal ptosis, is an abnormal condition in which the kidney drops down into the pelvis when the patient stands up.
  • The renal fascia is a layer of connective tissue encapsulating the kidneys and the suprarenal glands.
  • The deeper layers below the renal fascia are, in order, the adipose capsule of the kidney (or perirenal fat), the renal capsule and finally the parenchyma of the renal cortex.
  • Anterior attachment: Passes anterior to the kidney, renal vessels, abdominal aorta and inferior vena cava and fuses with the anterior layer of the renal fascia of the opposite kidney.
  • The attack of colic pain is called Dittel's crisis or renal paroxysm.

• Location and External Anatomy of the Kidneys

  • The kidneys are the primary functional organ of the renal system.
  • They are covered by the renal capsule, which is a tough capsule of fibrous connective tissue.
  • Resting on top of each kidney is an adrenal gland (adrenal meaning on top of renal), which are involved in some renal system processes despite being a primarily endocrine organ.
  • The renal artery branches off from the lower part of the aorta and provides the blood supply to the kidneys.
  • Renal veins take blood away from the kidneys into the inferior vena cava.