Renal Flashcards
How much of water makes up body weight
50-70%
How much of total body water content is intracellular?
2/3
How much of the total body water content is extracellular
1/3
what makes up the extracellular fluids?
Interstitial fluid, plasma
what percent of interstitial fluid makes up the extracellular content
3/4
what percent of plasma makes up the extracellular fluid
1/4
what’s a major factor for the health of the individual cell health
ECF
what is the functional unit of the kidney
nephron
how many nephron units/kidney
1 million
what makes up the nephron
the glomerulus and renal tubules
what is the glomerulus made up of
capillary network surrounded by bowmans capsule
List the sequence of renal blood flow
afferent arterioles send blood to the glomerular capillaries(1st capillary network) then to efferent arteries to the peritubular capillaries (2nd) then to venous capillaries.
can you explain the unusual vascular arrangement in the nephron
arterioles enter and exit the Bowman’s capsule to go through a two capillary bed system (series) with the peritubular capillary bed 2nd then to venous cap.
Why would a kidney transplant still show autoregulation btw 50-150
because there’s no nerve innervation, so no sympathetic and parasympathetic control
whats erythropoietin
hormone secreted by kidneys that make RBC’s
what is tuboglomerular feedback and what parts are involved
regulation of renal blood flow via juxtaglomerular apparatus & macula densa
Describe the ideal location of the juxtaglomerular apparatus
the juxtaglomerular cells & macula densa are closely associated with vacular pole of the nephron and the distal renal tubule to sense the GF composition and make adjustments to the arterioles
If overall blood flow to kidney is inadequate, what occurs
kidney releases large quantity of renin which will increase blood flow
whats the biggest cause for problems in the glomerular capillary membrane
Diabetes
what is nephrotic syndrome
leakage of very large amounts of protein from the glomerulus results in massive proteinuria
what is the result of nephrotic syndrome (pathophys)
edema and hypoproteinemia (low protein in blood)
creatinine clearance
measurement to assess GFR. serum creatinine is filtered by the glomerulus and filtrate concentrations are minimally altered by the tubules
what is a normal range of creatinine clearance
100-120
what would a creatinine clearance of around 60 indicate
loss of nephron units
what is inulin
a substance used to measure GFR because it can be completely filtered thru the glomerulus without being secreted nor reabsorbed
what is the fick principle
measurement of the GFR using serum concentration of inulin and urine concentration
where is Aldosterone produced/stored
adrenal gland
what directs the adrenal gland to produce/store aldosterone
pituitary gland
what controls the release of aldosterone
the renin-angiotensin-aldosterone system
what is aldosterone’s main function
increase Na+ reabsorption late distal tubules and collecting ducts
what percent of cardiac output contributes to renal blood flow?
about 22% (1200 cc’s/min)
In terms of Starling Forces, an increase in pressure within Bowman’s capsule will have what affect on the GFR
it will decrease
what is one reason/example of how there could be an increase in pressure within Bowman’s capsule
a urinary tract obstruction
Angiotensin II acts on:
constricting the efferent arteriole; increasing GFR but also increases reabsorptive forces for Na+ and H20 at peritubular capillaries
ADH:
antidiuretic hormone or vasopressin is a hormone from the posterior pituitary gland; increases h20 reabsorption during increased osmolarity (when body needs it, such as dehydration) vs. ECF/serum osmolarity low then ADH withheld and water excreted…
what is SIADH
syndrome of inappropriate secretion ADH ur body doesn’t withhold ADH properly so too much fluid retention, lower NA+ serum
what senses the osmolarity in the body fluids and tells the pituitary to secrete ADH
hypothalamus
what does atrial natriuretic peptide ANP do
inhibits reabsorption of Na+, H20 (opposing the action of aldosterone)
what secretes ANP & why
cardiac arterial cells, when there’s distension of atria ( too much preload)
what is the function of the parathyroid hormone
secreted in response to low serum Ca++ it increases renal reabsorption of Ca++ while phosphate reabsorption is decreased
how does the renal system contribute to acid base homeostasis
secrete and reabsorb HCO3- (bicarbonate) and excrete fixed acids such as NH4
what does renal hypoperfusion refer to
one of the 3 types of acute renal failure. When your body is hypovolemic caused by hemorrhage, GI fluid loss, or pancreatitis (3rd spacing)
what would cause post acute renal failure
calculi, tumors, and prostatic hypertrophy
what are some examples of intrinsic renal failure
atherosclerosis/blood clots, aortic aneurysm, glomerular disease, most commonly-acute tubular necrosis, others incude: myogloinuria, toxins, HTN, & interstitial nephritis
what is the time of onset in regards to acute renal failure
hours to days
what is the time of onset for chronic RF
months to years
what are some causes of CRF
Diabetes** HTN, obstruction, infection, a severe loss of nephrons
what would be a common manifestation of renal failure?
Oliguria (less than 400 ml/day…. a sign of decline in GFR
what are some signs/symptoms of CRF
uremia, hyperkalemia, metabolic acidosis, anemia, osteoporosis, volume overload, peripheral neuropathy, anorexia, and endocrine disturbances.
what is the range of specific gravity of urine
from 1035 (extremely concentrated) to 1001 (dilue).
what is an isotonic specific gravity
SG of 1010 isotonic with normal serum osmolarity (295 mOsm/l)
what are some abnormal constituents in urine?
glucose, protein, hematuria (RBC or hemoglobin), WBC’s, crystals, casts (indicates glomerulus bleeding) and bilirubin
How would you prevent ARF
proper hydration, treatment of Strep infections, caution with nephrotoxic drugs
Prevention for CRF
aggressive tx Diabetics, control HTN, adequate tx strep.
How is diabetes insipid us caused:
ADH is withheld so u have extreme thirst & pee out lots of dilute urine
About what % nephrons lost b4 see rise in creatinine level from .8-1.4
About 70%, hence y u can function with only one kidney
