Class 11: Multisystem dysfunction Flashcards
Tonicity + isotonic solution
-Fluid that has same osmolality as normal plasma: NS, D5W (hypotonic in body), RL
-Used to replace fluid loss
Tonicity + hypertonic solution
Fluid that has a higher osmolality than normal plasma: Admixed solutions e.g. TPN; 3% saline; mannitol; & D50S
Tonicity + hypotonic solutions
-Fluid that has a lower osmolality than normal plasma: 0.45% saline
-Used to replace fluid without giving electrolytes
Tonicity + isotonic
Placing a cell into an isotonic solution will have no net effect on the cell as the tonicity (osmolality) of the cell equals to the fluid
Tonicity + hypertonic
Placing a cell into a hypertonic solution will draw water out on the cell and the cell will shrink
Tonicity + hypotonic
Placing a cell into a hypotonic solution will shift fluid into the cell and the cell will swell & possibly burst
Anything other than a isotonic solution can…
-Cause fluid shifts in the vein used for infusion & consequently, the vessel may become more easily damaged and inflamed
Hypertonic cells..
Shrink and are damaged. (That’s why hypertonic solutions are generally infused through a central venous catheter)
Hypotonic cells…
Swell and infusion may infiltrate
Slide 5
Fluid shifts & edema + osmotic pressure GOES w/ card 1
-Power of the solution to draw water across a semi permeable membrane
-Isotonic crystalloid solution (NS & RL)
Fluid shifts & edema + oncotic pressure
-Plasma proteins exert this pressure and as a result pull water from the interstitial space into the vascular system
-Colloid solution (large proteins: albumin, globulin, fibrinogen)
Fluid shifts & edema + hydrostatic pressure…
-In the arterial (30-40 mmHg) and venous (10-15 mmHg) ends of capillary
-Force blood exerts against vascular walls
Fluid shifts & edema + capillary permeability
Is increased for pts with burns, or allergic inflammatory reactions
Oral fluid and electrolyte replacement in acid-base imbalances + isotonic solutions (D5W)
0.9% NS, RL, & D5W in 0.225% saline
Oral fluid and electrolyte replacement in acid-base imbalances + hypotonic solutions (0.45% saline)
D5W (physiologically)
Oral fluid and electrolyte replacement in acid-base imbalances + hypertonic solutions (D10W)
3.0% saline , D5W in 0.45% saline, & D5W in 0.9% NS
Edema + peripheral vs local
-Peripheral– Systemic swelling & pitting edema
-Local e.g. Ascites
Systemic signs of edema
BP & CVP alterations occur
Fluid shifts + serum osmolality
Measure of solute concentration of the blood [sodium, glucose and urea] (↑ = fluid volume deficit, ↓ = fluid volume excess)
Fluid shift + urine osmolality
Measure of solute concentration of urine [nitrogenous wastes – creatinine, urea, and uric acid] (↑ = fluid volume deficit, ↓ = fluid volume excess)
Risk of fluid shifts in infants
Infants have proportionately more body water, a lot of which is in the extracellular space. This is more easily lost from the body so infants can become dehydrated easily
Others at risk for fluid shifts
-Elderly, who can’t compensate for fluid shifts
-Anyone with GI problems
Sodium & volume imbalances nursing diagnosis + ECF volume excess
-Ineffective airway clearance r/t Na+ & H2O retention
-Risk for impaired skin integrity r/t edema
-Disturbed body image & altered body appearance r/t edema
-(P) complication of pulmonary edema or ascites