CH25 Clinical Terms

Exam 4 Review: Chapter 25: Clinical Terms

urination = micturition - The act of voiding urine which is under complex nervous regulation; stretch receptors respond when the bladder volume exceeds 200-400 mL, voluntary recognition of the sensory information is processed in the cortex to trigger an autonomic reflex in which parasympathetic impulses trigger contractor of the detrusor muscle in the wall of the bladder while relaxing the internal sphincter.

incontinence - The involuntary discharge of urine (or feces); urinary incontinence is more common in women than men; common causes include neurologic injury, birth defects, strokes, multiple sclerosis, and physical problems associated with aging.

retention - The involuntary withholding of urine (or feces); urinary retention is more common in men than women; it may be caused by stones lodged in the bladder or urethra or by urethral strictures (often from gonorrhea); prostatitis, prostatic carcinoma, or benign prostatic hypertrophy; or tumors or clots in the bladder, or spinal cord lesions and multiple sclerosis; patients with genital herpes may develop it from nerve involvement; it has also been reported following vigorous anal intercourse; any drug with anticholinergic effects or alpha adrenergic effects such as antihistamines, ephedrine sulfate and phenylpropanolamine may cause it.

urinalysis - The clinical laboratory examination (volume, color, turbidity, and odor) and analysis of urine by chemical and microscopic techniques, which is used to aid in the diagnosis or monitoring of many diseases, e.g., urinary tract infections (UTIs), diabetes mellitus, diabetes insipidus, kidney and liver diseases, etc., or to detect the presence of a specific substance, such as an illegal drug; standard chemical tests include glucose, bilirubin, ketones, specific gravity, blood, pH, protein, urobilinogen, nitrite, and leukocytes; standard microscopic categories are of sediment are crystals, cells, and casts.

glucosuria = glycosuria - A condition in which glucose is discharged in the urine; it is characteristic of untreated diabetes mellitus and may also be observed transiently after ingesting a rich meal.

anuria - The failure of the kidneys to form and discharge urine; it is indicative of kidney stones, tumors, renal failure or other serious renal or vascular pathology; dialysis or transplant may be required as therapy.

nocturia - A condition in which there is excessive urination (more than twice) at night; it may be present in individuals with untreated diabetes mellitus and diabetes insipidus, in certain cardiovascular disorders, and with urinary tract infections, and it is also more frequent in older people, especially males with enlarged prostate glands; it is also a side effect of taking diuretic medications and some other drugs.

polyuria - A condition in which there is excessive urination throughout the day and night (>2.5 liters per day); it may be present in individuals with untreated diabetes mellitus and diabetes insipidus, in certain cardiovascular disorders, in sickle cell anemia and early in renal failure; and those who ingest excessive amounts of fluids, especially those containing alcohol or caffeine; it is also a side effect of taking diuretic medications and some other drugs.

dysuria - A condition in which there is pain, discomfort, or a burning sensation during urination; it is typically indicative of a urogenital tract infection.

hematuria - A serious condition in which there is blood in the urine; it may be hemolyzed or nonhemolyzed, and may vary considerably in amount; it is typically indicative of a urogenital tract infection or injury; it may also be observed in children with coagulation disorders, sickle cell anemia or other diseases of the blood.

dialysis - (1) The separation of smaller molecules from larger molecules or of dissolved substances from colloidal particles in a solution by the difference in their rates of selective diffusion through a semipermeable membrane. (2) A necessary form of treatment in patients with end-stage renal disease or kidney failure, using an "artificial kidney" machine, or by peritoneal dialysis, with appropriate fluids and semi-permeable membranes, which allows the selective diffusion of wastes from the blood stream while limiting the loss of nutrients and electrolytes, and which may be required as often as three times a week. [The treatment is also called hemodialysis.]

hemodialysis - A necessary form of treatment in patients with end-stage renal disease or kidney failure, using an "artificial kidney" machine, or by peritoneal dialysis, with appropriate fluids and semi-permeable membranes, which allows the selective diffusion of wastes from the blood stream while limiting the loss of nutrients and electrolytes, and which may be required as often as three times a week. See also Dialysis from Merck & Co.

Sketch and label:

5. a simple hemodialysis system. List some substances that would be present in the dialyzing fluid at the same concentration as in the blood versus those that would be present in the dialyzing fluid at very low concentration.

Some substances that would be present in the dialyzing fluid at the same concentration as in the blood: sodium ions, chloride ions, calcium ions, acetate ions, bicarbonate ions, magnesium ions, glucose.

Some substances that would be present in the dialyzing fluid at very low concentration: hydrogen ions, potassium ions, phosphate ions, urea, creatinine.

Explain:

4. four different mechanisms by which diuretics can increase urine volume.

(1) osmotic diuretics - compounds which are soluble in body water but are not metabolized will be filtered into the urine, drawing water with them by osmosis.

(2) carbonic anhydrase inhibitors - compounds which block formation of bicarbonate ions in the PCT reduce the buffering capacity of blood; the accumulating hydrogen ions force the kidney to excrete more sodium ions, drawing water with them by osmosis.

(3) thiazides and related drugs - compounds which interfere with sodium reabsorption in the DCT, forcing the kidney to excrete more sodium ions, drawing water with them by osmosis.

(4) loop diuretics - compounds which interfere with the maintenance of the osmotic gradient between the cortex and the medulla of the kidney, forcing the formation of a dilute urine which draws water from the systemic circulation.