renal section Flashcards
1
Q
what type of bio transformations is the kidney capable of
A
phase 1 and 2
2
Q
lungs excrete _______ acids and kidneys excrete ________ acids
A
lungs: volatile
kidneys: non volatile
3
Q
when is EPO released via the kidney
A
when theres inadequate O2 delivery to kidney (anemia, reduced intravascular volume, hypoxia)
4
Q
what stimulates erythrocyte production
A
EPO stimulates stem cells in bone marrow
5
Q
what effect does PGE1 and PGE2 have on renal arterioles
A
vasodilation
6
Q
what effect does thromboxane A2 have on renal arterioles
A
constriction
7
Q
role of calcitrol with kidneys
A
- stimulates absorption of calcium from food
- instructs kidneys to reduce calcium and phosphate excretion
- increase deposition of calcium into bone
8
Q
increased PTH _____’s calcitrol
A
increases
9
Q
kidneys can synthesize _______ from amino acids
A
glucose
10
Q
the kidneys receive _____ of CO (________mL/min_
A
20-25% (1000-1250mL/min)
11
Q
How much of blood is filtered at glomerulus
A
20%
12
Q
how much blood is reabsorbed in peritubular capillaries
A
99%
13
Q
renal blood flow equation =
A
(MAP - renal venous pressure) / renal vascular resistance
14
Q
how does blood flow through the kidney?
A
renal arteries -> renal segmental artery -> interlobular artery -> articulate artery -> interlobular artery -> afferent arterioles -> glomerular capillary bed -> efferent arterioles -> peritubular capillaries (reabsorption and secretion) -> venues -> interlobular vein ->arcuate vein -> interloper vein -> renal segmental vein
15
Q
renal autoregulation includes
A
myogenic mechanism
JG apparatus
tubuloglomerular feedback
RAAS
prostaglandins
ANS
SNS
16
Q
lower chloride concentration in ultrafiltrate does what
A
triggers renin release to activate RAAS
17
Q
role of A2 and increase in GFR
A
constricts efferent arterioles
18
Q
go over RAAS pathway
A
angiotensin–>(renin) angiotensin 1–> (ACE) angiotensin 2
19
Q
5 roles of angiotensin 2
A
vasoconstriction (peripheral vessels and efferent arteriole)
increased aldosterone release from adrenal gland
SNS activation
increased ADH release from posterior ptuitary
increased thirst
20
Q
where is aldosterone produced
A
zona glomerulosa of adrenal gland
21
Q
what does aldosterone stimulate in kidney
A
Na/K/ATPase in principal cells of distal tubules and collecting ducts. H2O reabsorption and K/H excretion occurs
22
Q
what two electrolyte changes increase aldosterone release
A
increased K or decreased Na
23
Q
what is addisons
A
adrenocortical insufficiency (destruction of all cortical zones)
24
Q
what stimulates ADH release
A
increased osmolarity of ECF. increased sodium shrinks osmoreceptors in hypothalamus. initiates transport of ADH from hypothalamus to posterior pituitary.
increased BV via unloading of baroreceptors in carotid sinuses, transverse aortic arch, great veins, right atrium
25
how doe ADH restore BP
stimulates V1 (vasoconstriction, increase in IP3, DAG, Ca2+), increases SVR
stimulates V2 in collecting duct (increased cAMP), aquaporin 1 channels inserted into walls of collecting ducts, H2O reabsorption, decreased plasma osmolarity, increased urine osmolarity.
net result= expansion in plasma volume
26
where are prostaglandins produced
afferent arterioles
27
arachidonic acid is liberated from cell membrane in response to
ischemia, HoTN, NE, AT2
28
how does NSAIDs decrease RBF
inhibiting production of vasodilation prostaglandins
29
endotoxins release ________, which leads to renal vasoconstriction
leukotriene production
30
what does the myocardium release in response to distention
ANP and BNP
31
what is the role of natriuretic peptides
inhibit renin release (negative feedback for RAAS) vasodilation and decreased BP.
promotes Na/H2O excretion into collecting ducts
32
where are dopamine 1 receptors found
kidneys and splanchnic circulation
33
second messenger and function of DA1 receptors
cAMP (increased),
vasodilator, increase RBF, increases GFR, diuresis, Na excretion
34
where are dopamine 2 receptors found
present on presynaptic adrenergic nerve terminal
35
second messenger and function of DA2 receptors
cAMP (decreased),
function, decreases NE release
36
what is freely filtered at the glomerulus
water, electrolytes, glucose
37
what determines glomerular hydrostatic pressure
1. arterial BP
2. afferent arteriole resistance
3. efferent arteriole resistance
38
reabsorption in kidneys
substance transferred from tubule to peritubular capillaries
39
secretion in the kidneys
substance transferred from peritubular capillaries to tubule
40
what is excretion in the kidneys
substance removed from body in urine
41
what is the proximal convoluted tubule responsible for
bulk reabsorption of solutes and water
-water follows Na here via osmosis
-K/Cl/HCO3- follow Na in direct proportion
-organic bases, acids, and hydrogen ions are secreted into proximal tubule via Na counter transport mechanism
42
what percent of ions are absorbed in proximal tubule
65%
43
what is the primary role of the descending loop of henle
countercurrent mechanisms and high permeability to H2O
-primary function is to form concentrated or dilute urine.
-separates handling of Na/H2O
- theres an osmotic gradient, highly permeable to H2O and moderately permeable to ions
44
vasa recta
peritubular capillaries that run parallel to the loop of hence. returns reabsorbed water to the blood allowing osmolarity in peritubular insterstitium to remain high
45
what is the primary role of the ascending loop of henle
countercurrent mechanisms and no H2O permeability
- unlike descending LOH, thin and thick segments are not permeable to H2O
-ions pumped from tubular fluid into peritubular interstitium. Na/K/Cl co transporter is most important pump.
-since H2O cannot follow Na into peritubular interstitium, tubular fluid becomes more dilute and peritubular interstitium becomes concentrated
46
primary role of distal convoluted tubule
fine tune solute concentration
-Na(5%) is reabsorbed and Na/K/HCO3- follow via sodium co transport mechanism
-late distal tubule is impermeable to H2O except in the presence of aldosterone or ADH
-home to juxtaglomerular apparatus
-adjusts urea concentration
47
primary role of collecting duct
regulates final concentration of urine
-reabsorbs Na
-ADH and aldosterone also work in collecting duct
-ANP inhibits Na/H2O reabsorption
-adjusts hydration concentration
48
what is the function of carbonic anhydrase in the proximal tubule? (5 steps)
1. CO2 and H2O diffuse into proximal convoluted tubule cells
2. carbonic anhydrase facilitates production of H2CO3
3. H2CO3 dissociates into H and HCO3-
4. HCO3- diffuses into interstitium then blood
5. H+ is returned to tubal lumen
49
carbonic anhydrase inhibitors noncompetitively inhibit
carbonic anhydrase in the cells that make up the proximal tubule.
50
what do carbonic anhydrase inhibitors reduce the reabsorption of?
HCO3, NA, H2O
51
examples of carbonic anhydrase inhibitors
acetazolamide 250-500mg
52
side effect and ultimate uses for carbonic anhydrase inhibitors
mild metabolic acidosis. used to treat high altitude sickness and central sleep apnea since it increases respiratory drive
53
what are osmotic diuretics (make up)
sugars that undergo filtration but not reabsorption
54
role of osmotic diuretics
inhibit water reabsorption in the proximal tubule (primary site). transiently increases plasma osmolarity
55
how loop diuretics exert their effect
disrupt the Na/K/2Cl transporter in the medullar region of the thick portion of the ascending loop of henle (primary site).
the amount of sodium that remains in the tubule overwhelms the distal tubules' reabsorption capability so the patient eliminates large volumes of dilute urine
56
examples of loop diuretics
furosemide, bumetanide, ethacrynic acid
57
clinical uses of loop diuretics
acute pulmonary edema, AKI, CHF, increased Ca2+, HTN, anion DO, ICH, mobilization of edema fluid
58
key complication of loop diuretic
hypochloremic metabolic alkalosis
59
thiazides inhibit
Na/Cl co transporter in distal tubule. increases Ca reabsorption and serum calcium
60
SE of thazides
hyperglycemia, increased Ca, hyperuricemia (gout patients), hypokalemic hypochlorremic metabolic alkalosis, hypovolemia, HLD sexual dysfunction
61
meds that can increase risk of hyperkalemia
NSAIDS (decreases renin and atII mediated aldosterone release)
BB (suppression of aldosterone secretion at adrenal cortex and reduction in K uptake)
ACEI
62
tests and normal values of glomerular function include
BUN 10-20mg/dL
serum creatinine .7-1.5mg/dL
creatinine clearance 110-150mL/min
63
tests and normal values of tubular function (concentrating ability) include
fractional exertion of sodium 1-3%
urine osmolality 65-1400mOsm/L
urine sodium concentration 130-260mEq/day
urine specific gravity 1.003-1.030
64
100% increase in creatinine = ___________ in GFR
50% decrease
65
what is fractional exertion of sodium Fe(na)
relates to Na clearance to creatinine clearance.
66
if FeNa is less than 1%
more Na is conserved relative to the amount of creatinine cleared. this suggests pre renal axotemia
67
If FeNa is greater than 3%
more Na is excreted relative to the amount of creatinine cleared. suggests impaired tubular function
68
pre renal oliguria
FeNa
Urinary Na
urine osmolality
BUN:creatinine ratio
sediment
FeNa <1
Urinary Na <20
urine osmolality >500
BUN:creatinine ratio >20:1
sediment: normal, possible hyaline cysts
69
acute tubular necrosis
FeNa
Urinary Na
urine osmolality
BUN:creatinine ratio
sediment
FeNa >3%
Urinary Na >20
urine osmolality <400
BUN:creatinine ratio 10-20:1
sediment: tubular epithelial cells, granular casts
70
three systems used to classify AKI
1. RIFLE (risk, injury, failure, loss, end stage)
2. AKIN (acute kidney injury network)
3. KDIGO: kidney disease improving global outcomes
71
causes of pre renal injury
hypo perfusion, decreased CO, systemic vasodilation, renal vasoconstriction, increased intra abdominal pressure
72
treatment of pre renal injury
IVF, hemodynamic support, PRBC's, renal prostaglandins mediate vasodilation. avoid NSAIDS.
improvement in UOP after IVF confirms pre renal azotemia
73
causes of intra renal injury
ATN, ishemia, nephrotoxic drugs, parenchymal dysfunction
74
treatment of intra renal injury
restore renal perfusion, supportive
75
excessive use of .9% NaCl can cause
hyperchloremic metabolic acidosis
76
vasopressin constricts what in the kidney
efferent arteriole
77
do not use the following to prevent or treat AKI
low dose dopa, fenoldopam, ANP, recombinant human (Rh) IGF 1
78
avoid which abx
ahminoglycosides, amphotericin B (IV)
79
stages of chronic kidney disease (5)
1. GFR >90
2. GFR 60-89
3. GFR 30-59
4. GFR 15-29
5. GFR < or = 15
80
s/sx of uremia
anemia, fatigue, n/v, anorexia, coagulopathy
81
1st line tx for uremia
desmopressin
82
2 ways CKD increases anemia
decreased production of EPO via kidneys, normochromic normocytic anemia
excess PTH replaces bone marrow with fibrotic tissue which increases anemia.
83
CKD shifts oxyhgb dissociation curve
to the right to help with metabolic acidosis
84
how does osteodystrophy happen in CKD
caused by decreased vitamin D production, secondary to hyperparathyroidism. PTH demineralizes bone to restore serum calcium conentration
85
5 indications for HD
1. volume overload
2. increased K (over 6)
3. severe metabolic acidosis
4. symptomatic uremia
5. OD with a drug
86
FDA recommend that sevoflurane be administered at a rate of __L/min for no more than ___ MAC hours
1L/min for more than 2 MAC hours.
87
best nondepolarizing NMB's for CKD
cisatracurium and atracurium
88
do you need an increased or decreased dosage of propofol in CKD patients?
increased related to hyper dynamic circulation and disruption of BBB secondary to azotemia
89
better opioid analgesics for CKD patients (that dont have metabolites that can accumulate) include
fentanyl, sufentanyl, alfentanil
90
radiographic contrast media causes nephrotoxicity by
ischemic injury due to vasoconstriction in renal medulla, direct cytotoxic effect
91
use what kind of contrast with CKD?
non ionic iso or low osmolar contrast instead of hyperosmolar
92
strategies to prevent injury from free myoglobin include
maintenance of RBF and tubular flow with IV hydration, osmotic diuresis with mannitol, keep UOP >100-150mL/h, administer NaHCO3 or acetazolamide to alkalinize the urine
93
two ways sevo can theoretically impair renal functoin
1. compound A
2. free fluoride ions
94
calcineuron inhibitors
are immunosuppressant agents that prevent the rejection of transplanted organs. sirolumus is a non cal
95
sirolumus
non calcineurin inhibitor that carries a much lower risk of nephrotoxity
96
most common approach to TURP (anesthetic)
spinal (T10 level necessary)
97
distilled H2O irrigation solution for TURP
osmolarity
pros
cons
0 mOsm/L
good surgical visibility
increases risk of TURP syndrome, hyponatramia, hemolysis, hemoglobinuria, renal failure
98
glycine irrigation solution for TURP
osmolarity
pros
cons
200 mOsm/L
decrease risk of TURP syndrome
increased ammonia, decreased LOC, transient post visual syndrome, blind/blurry vision for 24-48h, glycine is inhibitory transmitter in eye
99
sorbitol 3.3% irrigation solution for TURP
osmolarity
pros
cons
165 mOsm/L
decreased risk of TURP syndrome
increased BG, osmotic diuresis, lactic acidosis
100
mannitol 5% irrigation solution for TURP
osmolarity
pros
cons
275 mOsm/L
osmolarity similar to plasma, renal filtration and excretion (no metabolism)
cons: osmotic diuresis, transient plasma expansion
101
NaCl .9% irrigation solution for TURP
osmolarity
pros
cons
303 mOsm/L
osmolarity just a bit higher than plasma. absent of many SE's associated with other solutons
cons: can only be used with bipolar electrocautery. do not use with monopoly.
102
presentation of TURP syndrome
triad: HTN, bradycardia, change in mental status
103
treatment of TURP syndrome
support with O2/CV. labs: lytes, HCT, creatinine, glucose
12 lead,
if Na >120 then restrict fluids and give furosemide
if <120 then give 3% NaCl at <100mL/h
104
bladder perf presentation and tx
abdominal and shoulder pain, decrease in irrigation fluid return
tx: supportive. serial H/H, emergent suprabupic cystotomy or even exlap
105
absolute contraindications to lithotripsy
pregnancy and risk of bleeding
106
relative contraindications to lithotripsy
Pacer/ICD. calcified aneurysm of aorta or renal artery, URI, obstruction, morbid obesity
107
anesthesia considerations for percutaneous lithotripsy
used when ESWL ineffective
stents placed
GETA and in prone
irrigation used
pneumothorax is a complicaton
108
anesthesia considerations for laser litho
breaks up stone, irrigation used, pts are usually in lithotomy.
109
how to calculate creatinine clearance (men)
(140- age) * (weight in kg) / (serum creatinine /72)
110
how to calculate creatinine clearance (men)
(140-age)* (kg) / (serum creat*72)
111
how to calculate creatinine clearance (women)
.85 (140-age)*(kg)/ (serum creat *72)
