E3 Fluid & electrolytes Flashcards
What does body fluid do?
- Transport nutrients & waste to & from cells
- Solvent for electrolytes
- Body temp
- digestion
- elimination
- acid-base balance
- lubrication of joints & body tissue
_____% of adults body weight is water
50-60%
How much of water is intracellular and extracellular? Parts of extracellular?
Intra- 70%
Extra- 30%
1. Interstitial fluid- btwn cells
2. Intravascular fluid-plasma (nonRBCs)
Describe Osmosis
Movement of water from low solute concentration to high solute concentration across semipermeable membrane
Describe Diffusion
Movement of molecules from high concentration to low concentration
Osmotic pressure
the amount of pressure needed to prevent the movement of water across a cell membrane
Colloids
Substances that increase colloid oncotic pressure
Move fluid from interstitial space to plasma (blood)
What are the 3 primary colloids?
-Albumin
-Globulin
-Fibrinogen
Colloids can be measured with ______ and decreaes with ______
total protein level
age & overall nutrition
Describe Hydrostatic pressure
Force of fluid pushing against cell membrane (vessel wall)
Generated by BP
At capillary level, major force that pushes water out of the vascular space into interstitial space
Aids the supply of nutrients to the tissues of the body
Describe Oncotic pressure
aka colloid osmotic pressure
major colloid is albumin
Plasma has LOTs of colloids, interstitial space has little
Plasma proteins attract water, pulling fluid from tissue space into vascular space
Helps remove metabolic waste from tissues
Electrolytes influence:
-Fluid balance
-Acid-base balance
-Nerve impulses
-Muscle contraction
-Heart rhythm
Concentrations of electrolytes are dependent on
-Electrolyte intake
-Electrolyte absorption
-Electrolyte distribution
-Electrolyte excretion
Intracellular electrolytes & charges
Potassium K+
Magnesium Mg+2
Phosphorus P-3
Extracellular electrolytes & charges
Sodium Na+
Chloride Cl-
Bicarbonate HCO3-
Sodium normal lab value
136-145 meq/L
Potassium normal lab value
3.5-5.0 meq/L
Magnesium normal lab value
1.7-2.2 mg/dl
Calcium normal lab value
9-11 mg/dL
Phosphate normal lab value
3.2-4.3 mg/dL
What follows sodium?
Water
What is Hyponatremia and the causes?
Low Na+ <136
-Gi losses (N/V/fistulas/NG suction)
-Renal losses (Diuretics, adrenal insufficiency, Peeing)
-Skin losses (burns, wound damage)
-Fasting diet, polydipsia (water intoxication)
-Excess hypotonic fluid
Hyponatremia S/S
-CONFUSION/ ALTERED LOC (swelling of brain cells)
-Anorexia & Muscle weakness
-Can lead to seizures/comas
What is Dilutional Hyponatremia & symptoms?
- Hypervolemia = Too much water
- Increase BP
- Weight gain
- Bounding rapid pulse
- Increase urine specific gravity
What is Depletional Hyponatremia & symptoms?
- Hypovolemia = Absolute loss of Na+ (fluid loss)
- Decrease BP
- Tachy pulse
- Dry skin
- Weight loss
- Decreased urine specific gravity
Hyponatremia treatment
- Sodium replacement (SLOWLY)
- PO- Sodium Bicarbonate
- IV-Normal Saline (0.9%)
- Fluid restriction
- Treat underlying problem (Water intoxication or not eating)
MOA of Sodium Bicarbonate
Dissociates to provide bicarbonate ion which neutralizes concentration and raises blood and urine pH
Also, increases concentration of sodium in plasma
Indication of Sodium Bicarbonate
Metabolic Acidosis
How is Sodium Bicarbonate administered?
PO only
-Do not give IV: Vesicant at high concentrations (Only given for acid-base imbalance through central line)