Fluid & Hemodynamics Flashcards
Edema
Excess fluid in interstitial space. Extracellular space, outside of vessel.
Pitting vs. non-pitting
Pitting = transudate (e.g. CHF). Non-pitting = EXUDATE, lymphatics eventually
3 fluids in Edema
Transudates, exuedates, and lymphedema
Transudates
Oncotic pressure keeps fluid in vessels (80% is from albumin). Hypoalbuminemia –> transudate leaking. Hydrostatic pressure pushes fluid out.
What produces transudates?
Decreased oncotic pressure and increased hydrostatic pressure. Albumin made in liver. Chronic liver disease -> low albumin. Malabsorption, nephrotic syndrome, third degree burn, kwashiorkor.
Bee sting
Exudate - Anaphylactic reaction is histamine (Type-1) -> increased vessel permeability. Airway, Epi (1:1000 SQ)
Cirrhosis of liver
Pitting edema and ascites. Ascites: transudate; dec. oncotic pressure and inc. hydrostatic in portal HTN. Legs: transudate from dec. oncotic pressure.
Non-pitting type of edema 2/2 s/p radical mastectomy
Lymphedema. Lymphogranulonum venereum - scarring lymphatics; Peu D’ Orange. Risk of lymphangiosarcoma.
ECF
Vascular (1/3) and interstitial (2/3)
ICF
2/3 larger than ECF.
For every 3 L NS you put into a person
1 L in vascular; 2 L in interstitial fluid.????
Osmolality
Measure of solutes in a fluid. Sodium, glucose, BUN are major compartments. 2 x Na (140) + glucose/18 + BUN/3
Osmosis
Na and Glucose are limited to ECF. Na is the main determiner of osmosis since osmolality is determined primarily by [Na]ecf. Urea is PERMEABLE so doesn’t control osmosis
Hyperglycemia
ICF -> ECF. DILUTIONAL Hyponatremia
Tonicity
Referred against plasma tonicity. Isotonic, hypotonic, hypertonic. Tonicity is related to: Total body Na / Total body water
Isotonic loss of fluid
Lost equal amounts of Na+ and water. Mostly loss of ECF. Serum Na+ conc. is normal. Examples - hemorrhage, diarrhea.
Most common cause of low osmolality in plasma =
Hyponatremia. ICF will gain water. (e.g. SIADH 2/2 SCLC -> restrict WATER NOT Salt). Serum Na+ < 120 think SIADH
Hypertonic loss of fluid
Lost more salt than water. Hyponatremia. E.g. - diuretics.
SIADH
T2DM - chloropropamide (sulfonylureas) —> SIADH
Hypertonic gain of fluid
Still get hyponatremia. Pitting edema states (RHF, cirrhosis)
Total body Na+
When increased = PITTING EDEMA; Most of your Na+ is in interstitial (3/4 of ECF).