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Chapte_19
| Term | Definition |
|---|---|
| renal system | a bodily system responsible for clearing waste products from the blood while maintaining proper fluid and electrolyte balance; also called the urinary system |
| kidneys | a pair of organs that filter blood for metabolic by-products and waste substances and also balance fluids and electrolytes in the body |
| ureter | a duct that transports the waste products and excess fluid from the kidneys to the bladder |
| urinary bladder | a sac located in the pelvic region that collects and holds urine until the fluid exits the body during urination |
| urethra | a canal that discharges urine and in men, carries semen as well as urine |
| adrenal glands | a pair of glands located on top of the kidneys |
| renal artery | an artery that branches off from the abdominal aorta and brings blood into the kidneys |
| renal vein | a vein that returns blood that has been filtered in the kidneys to the bloodstream |
| renal cortex | the outer layer on the kidneys that is responsible for hormone production |
| renal medulla | tissue found in middle, body of each kidney that is made up of many triangle-shaped sections that perform filtration |
| nephron | the functional filtering unit of the kidney |
| afferent arteriole | the entrance to the nephron where blood containing fluid and waste products enter |
| Bowman’s capsule | a cup-shaped structure in the kidneys that filters fluid and waste products out of the blood by pressure |
| glomerulus | a structure in the Bowman's capsule that consists of a capillary tightly folded |
| glomerular filtration | the first step in urine production and the maintenance of fluid balance whereby large molecules are not filtered out, but most fluids and other smaller substances are |
| efferent arteriole | an arteriole whereby blood leaves the Bowman’s capsule and renters the circulation |
| filtrate | fluids and by-products filtered out of the blood in the glomerulus that continue on through the nephron |
| loop of Henle | a part of the nephron where molecules selectively reenter the bloodstream via several mechanisms |
| filtration | the process of substances moving across the membranes due to the force of pressure |
| reabsorption | the process of absorbing substances from the nephron back into the bloodstream |
| secretion | the process of elaborating or releasing a product |
| anuria | the inability to produce urine |
| aldosterone | a hormone that regulates the rate and volume of urine production |
| antidiuretic hormone (ADH) | a hormone that regulates the rate and volume of urine production |
| internal urinary sphincter | an involuntary muscle that keeps urine from flowing back into the ureters once it enters the bladder |
| external urinary sphincter | a voluntary muscle that holds urine in the bladder before it exits the body |
| detrusor muscle | a muscle in the bladder that contracts and pushes out urine |
| micturition | the process of urination |
| urinary retention | a condition that occurs when the kidneys make urine but the micturition process does not function properly and, consequently, urine accumulates in the bladder |
| incontinence | the inability to control the external urinary sphincter, thus allowing urine to leak out of the bladder |
| nephrotoxicity | direct damage to kidney tissue as a result of exposure to drugs or other chemicals |
| urinary tract infection (UTI) | an infection that usually occurs in the bladder but can affect any part of the urinary system |
| cystitis | a lower urinary tract infection involving the bladder |
| pyelonephritis | an upper urinary tract infection affecting the kidneys |
| prostatitis | a prostate infection in men |
| spastic bladder | a malfunction of the detrusor muscles in the bladder, causing contraction and frequent urination |
| antispasmodics | a drug class used to treat spastic bladder and urinary frequency that works by inhibiting acetylcholine in the autonomic nerves that control involuntary bladder contraction and emptying |
| benign prostatic hyperplasia (BPH) | a chronic condition that happens in men as the prostate gland enlarges with age |
| prostate-specific antigen (PSA) | a laboratory test that can screen for benign prostatic hyperplasia and more serious prostate problems |
| alpha blockers | a class of drugs that is used for patients with benign prostatic hyperplasia that work by inhibiting the alpha-1 receptors that relax smooth muscle in the prostate and bladder |
| 5-alpha reductase inhibitors | a drug class used for benign prostatic hyperplasia and male-pattern hair loss that work by inhibiting the conversion of testosterone into dihydrotestosterone (DHT) |
| acute renal failure | a condition that occurs as a result of some type of damage, either physical or chemical, or lack of blood supply to the kidneys; results in altered urine production and filtering function; reversible in many cases |
| chronic kidney disease (CKD) | a condition that involves progressive damage or results in the death of kidney tissue over time; eventually may require kidney transplant; not reversible |
| blood urea nitrogen (BUN) | a laboratory test used to monitor the concentration of urea and nitrogen in the blood; indicator of kidney function |
| serum creatinine (SCr) | a laboratory test used to monitor the concentration of creatinine in the blood; marker for kidney function |
| creatinine clearance (CrCl) | a calculation that estimates f kidney function while taking into account such factors as age and gender |
| glomerular filtration rate (GFR) | a calculation that estimates kidney function while taking into account such factors as age and gender |
| Cockcroft and Gault equation | the most common formula to calculate creatinine clearance |
| dialysis | an artificial method of filtering blood and correcting the electrolyte imbalances caused by renal failure |
| hemodialysis | a method of dialysis that is accomplished by diverting blood flow through a machine that mechanically filters the blood and returns the blood to the body |
| peritoneal dialysis | a method of dialysis that is accomplished by putting dialysate (a special fluid that draws toxins from the body into itself) into the abdominal cavity and leaving it there for a period of time then removing it |
| diuretics | a drug class used either to improve urine output in renal failure or to reduce blood volume in high blood pressure |
| thiazide diuretics | a drug class used to treat hypertension and works by inhibiting reabsorption of sodium and chloride ions in the distal tubule of the nephron |
| loop diuretics | a drug class used to treat renal failure and works by inhibiting reabsorption of sodium, chloride, and water in the ascending loop of Henle |
| potassium-sparing diuretics | a drug class used to treat hypertension and works by blocking the exchange of potassium for sodium that takes place in the distal tubule |
| aldosterone antagonists | a drug class used to treat hypertension and hyperaldosteronism (the overproduction of aldosterone) and works by inhibiting a hormone that promotes fluid retention |
| carbonic anhydrase inhibitors | a drug class used to treat open-angle glaucoma and diuresis in congestive heart failure; works in the nephron by increasing excretion of bicarbonate ions, which carry sodium, potassium, and water into the urine |
| potassium supplement | an agent that replenishes potassium levels in the body |
| osmotic diuretics | a class of drugs used to treat severe trauma, cardiac operations, and elevated intracranial pressure; works by increasing the concentration of the filtrate which hinders reabsorption of water into the bloodstream from the renal tubules |
| saw palmetto | an herbal treatment used to treat benign prostatic hyperplasia symptoms, such as frequent or painful urination, as well as urination hesitancy and urgency |
| cranberry juice | a beverage used for prevention of recurrent urinary tract infections |