pelvis-collects urine for excretion

(Perfusion)

produce urine

functional unit of the kidneys

productions of theses ceases at birth

1.3 million per kidney

tell us about osmolity

1. glomerulus

2. proximal convoluted tubule,

3. loop of henle

4. distal convoluted tubule

which is the blood/ kidney interface, plasma is filtered from capillaries into the bowman's capsule

filters

• less wast is removed
• more waste reamins in the blood
• nitrogenous compounds build up in the blood

blood urea nitrogen

rough estimate of renal function

amount of urea in blood

varies with diet

more sensitive indicator of kidney funciton

excreted entirely by kidneys

dont worry about low levels, but worry about high. This means kidneys are not removing what they should be!!!

Most sensitive determinant of renal function.

the rate at which fluid is filtered by the glomerulus

about 90-140 mls decrease with increase age

has an inverse relationship with serum creatinine

1. renal blood flow and renal perfusion pressure
2. the hydrostatic pressure difference between the tubule and the capillaries
3. the surface area available for ultrafiltration

60%

decreased blood supply

ex. shock, dehydration, vasocontriction
renal tublues remain intact and avidly conserve salt and water in the fact of sensed renal hypoperfusion often called "acute renal success"

5%

urine flow is blocked

ex. stones, tumors, enlarged prostate

caused by obstruction below level of the kidneys

35%

damage within the kidneys

kidney tubule function is decreased

ex. ischemia, toxins, intratubular obstruction

• exposure to nephrotoxic agents
• heavey metals
• radiopaque
• acute glomerulonephritis
• uric acid crystals
• severe crushing injuries

drop in urine output (<15ml/hr)

Na <135

K increases

BUN and Creatinine increase

this is the inability to urinate

seen by < 50 ml/hr

>400ml/hr

S&S of electrolyte imbalance

K+ falls

U/O gradually returns to normal

begin 2-3 weeks after injury can take up to 6-12 months

largely supportive

discontinue nephrotoxic agent

loop diuretics

hemodialysis

monitor I&O

monitor electrolytes

mortality remains around 50%

2/3 oliguric phase

1/3 diuretic phase

mortality rate is highest with patient with marked tissue destruction ex. crushing injuries, severe trauma

  Diminished renal reserve

renal insufficiency

renal failure

end stage renal disease

nephrons are working as hard as they can

GFR 50% normal

normal BUN/creatinine

nephrons acan no longer regulate urine density

Azotemia, anemia, increased b/p, polyuria, nocturia

nephrons can no longer keep blood compostion normal

GFR <20%

edema, metabolic acidosis, hypocalcemia

Uremia

urine in the blood.

• renal filtering function decreases, altered fluid and electrolyte balance
• wastes build up in  blood-azotemia, inreased creatinine and BUN
• Kidney metabolic functions decrease, decrease inerythropoietin and vitamin D

hyperkalemia

metabolic acidosis

increase serum creatinine, BUN, phosphate,

decrease calcium

fluid volume excess

anemia

infections

ecchymosis

cardiovascular consequences of CRF

tums can be taken for people with CRF

phoslo- phosphate binder, helps bring levels down

• because severe trauma can cause renal failure
• could go into shock, prerenal failure shock

More than 50% because of the high serum levels and the BUN

Kaying developed ARF after emergency surgery for a severed left leg.

Why would leg damage cause renal failure?

she came in with a serum creatinine of 1.2 but now it is 5.6mg

her BUN is 86mg

What is his remainning kidney functions?

is the most common method used to treat advanced and permanent kidney failure

your blood is allowed to flow, a few ounces at a time, through a special filter that removes wastes and extra fluids. The clean blood is then returned to your body. Removing the harmful wastes and extra salt and fluids helps control your blood pressure and keep the proper balance of chemicals like potassium and sodium in your body.

GFR= 10ml a min

heparin injected to prevent clotting

placed in a central vein

tunneled to the disired site

a cuff is attached to the catheter and helps prevent bacteria from migrating up the subcutaneous tunnel

2-4 hours, 2-3 days a week

problems: infection- then you cant use the split anymore.

• alot do it at night 10-12 hours
• weight is important, dont want them to gan fluid weight
• need to take temp everyday
• can be done at home
• pull out toxin slower then hemodialysis
• abdomen will be puchy
• fluid left in for a couple of hours then comes out
• need it warm
• 2L injected in 10-20 mins
• 4 exchanges 7 days a week.

ARF- micro hematuria, normal sized kidneys on ultrasound, pulmonary edema

CRF- osteodystrophy, metabolic acidosis

which ones are ARF/CRF

• microscopic hematuria?
• osteodystrophy?
• normal sized kidneys on ultrasounds?
• pulmonary edema?
• metabolic acidosis?

Mr. Chow age 64 has acute renal failure. he has a history of CRF, secondary to increase b/p and the following are his labs

serum potassium is 6.2

BUN 108

HCO3 14

he is somnolent and confused. is dialysis indicated for Mr. Chow?