Fluid Volume Excess (Overload)/Hypervolemia
Aldosterone
-Steroid, Mineralocorticoid -When blood volume gets low (vomiting, hemorrhage, etc): Aldosterone secretion increases= retain sodium/water=blood volume goes up -Diseases with too much Aldosterone: Cushings, Hyperaldosteronism (AKA Conns Syndrome) -Disease with too little Aldosterone: Addison's (decrease in retention of sodium/water=fluid volume defecit)
What are 2 important hormones in regulation of fluid volume?
1. Aldosterone -Steroid, Mineralocorticoid -Found in adrenal glands -Normal action: when blood volume gets low (vomiting, hemorrhage, etc), Aldosterone secretion increases to tell the body to retain sodium and water. Blood volume goes up. -Diseases with too much Aldosterone: 1) Cushings (too much steroids in general) and 2) Hyperadosteronism (AKA Conn's Syndrome, hyperactive adrenal gland(s)) -Disease with too little Aldosterone: Addison's (decreased sodium and water, causes a fluid volume DEFECIT) 2. Anti-Diuretic Hormone (ADH) -Normally makes you retain water -Consider differences between if you have too much or too little ADH
What are the 4 hazards of immobility due to the bedrest effect on diureses?
1. DVT 2. Pneumonia 3. Kidney stones (from dehydration) 4. Constipation
Name 3 Causes of Hypervolemia and why/how they cause it?
1. Heart Failure: Heart is weak, cardiac output goes down, kidney perfusion goes down, urinary output goes down, and volume stays in the vascular space (particularly the heart and causes hypertrophy) 2. Renal Failure: Kidneys aren't working 3. Things with lots of Sodium (Effervescent soluble meds (i.e. Alka-Seltzer), canned/processed foods, IV fluids with sodium)
Normal level: Urine Specific Gravity
1.002-1.030
Normal level: Serum Sodium
135-145 mEq/L
Vasopressin
Anti-Diuretic Hormone (ADH)Vasopressin (Pitressin) or desmopressin acetate (DDAVP) Used as ADH replacement for Diabetes Insipidus Works to maintain fluid/blood volume and therefore blood pressure
What is ANP?
Atrial Natriuetic Peptide (ANP) causes excretion of sodium and water. *In hypervolemia, fluid goes backward to heart and stretches atria. Stretched atria release ANP to diurese fluid.
What is the effect of bedrest on diuresis? How?
Bed rest induces diuresis. *Releases ANP and decreases production of ADH.* ANP: Atrial Natriuetic Peptide: Fluid goes backward to heart and stretches atria; stretched atria release ANP to diurese ADH: Anti-diuretic Hormone
Always PUSH FLUIDS for clients on bedrest. Why?
Bed rest induces diuresis. Maintain fluid balance. To avoid 4 hazards of immobility 1. DVT 2. Pneumonia 3. Kidney stones (from dehydration) 4. Constipation
Normal level: Central Venous Pressure
Central Venous Pressure (CVP) aka "RAP" Right Atrial Pressure 2-6 mmHg 5-10 cmH2O Depends on which measuring device is being used
Problems that influence ADH levels
Diabetes Insipidus (too little ADH) Any condition that can lead to increased ICP: craniotomy, head injury, sinus surgery, transphenoidal hypophysectomy
S/S of Fluid Volume Excess
Distended neck veins/peripheral veins. Vessels are full. a. Increased Jugular Vein Distention (JVD), Increased BP b. Peripheral edema/third spacing: vessels can't hold any more, so they start to leak c. Central venous pressure (CVP): measured where? right atrium: number goes up in FVE. More volume more pressure. >6 mmHg or >10 cmH2O d. Lungs sound wet; listen to bases in back = shortness of breath e. Polyuria (kidneys are trying to diurese) f. Tachycardia (to keep blood pushing forward; if it goes backward, it goes into the lungs and causes pulmonary edema. Palpate radial artery & it will feel full and bounding) g. Hypertension h. Fast weight gain: "Any acute (fast) gain or loss isn't fat, it's fluid."
Treatment for too little ADH in Diabetes Insipidus
Drug vasopressin (Pitressin) or desmospressin acetate (DDAVP) may be used as ADH replaccement in Diabetes Insipidus
S/S of Too Little ADH
Fluid Volume Defecit (Hypovolemia)=shock=death Loose (diurese) water DI (diabetes inspidus: not enough ADH; dilute urine) "Sneaky, less obvious way to die. Pee yourself to death." Urine: diluted (urine specific gravity <1.002) Blood: concentrated (increase in serum sodium >145, hematocrit >48% or 52%) Treatment? Drug vasopression (Pitressin) or desmopresson acetate (DDAVP) may be used as ADH replacement in Diabetes Insipidus
S/S of Too Much ADH
Fluid Volume Excess (Hypervolemia) Retain water SIADH (Syndrome of Inappropriate Antidiuretic Hormone) Urine: concentrated (increase in urine specific gravity >1.030) Blood: diluted (decrease in serum sodium <135, hematocrit <37%, 45%)
Fluid Retention: Think ____________ first
Fluid retention: Think heart problems first
Explain heart failure
Heart is weak Cardiac output goes down Kidney perfusion goes down Urinary output goes down Fluid builds up in heart and causes hypertrophy Heart cannot pump as effectively Right vs. Left side: Right side has systemic buildup of fluid; Left side has lung buildup of fluid
Anti-Diuretic Hormone (ADH)
Hormone that Retains Water (increases blood volume, increases blood pressure) "With ADH, think H2O" -Think of differences between too much vs. too little ADH -Found in the pituitary gland
Where is ADH found?
In the pituitary gland IN YOUR HEAD *This means that if there is a head issue, there may be a pituitary gland issue, and therefore an ADH issue. *Key words to make you think potential ADH problem (too much or too little): craniotomy, head injury, sinus surgery, transsphenoidal hypophysectomy, or any condition that leads to INCREASED ICP (intracranial pressure) can lead to an ADH problem
Normal level: Hematocrit (Hct)
Male 45-52% Female 37-48%
Right-Sided vs. Left-Sided Heart Failure
Right-sided: Fluid buildup is systemic Left-sided: Fluid buildup is in lungs; "wet lungs"
Definition of hypervolemia
Too much fluid in the vascular space *Think of a garden hose with the water turned all the way up
What is the vascular space?
Veins, arteries, capillaries, heart
Treatment for Fluid Volume Excess
a. Low sodium diet/restrict fluids b. I & O and daily weights c. Diuretics **Monitor lab work for dehydration and electrolyte problems (specifically hypokalemia) -Loop: Furosemide or Bumetanide -Hydrochlorothiazide -Potassium-sparing: Spironolactone Aldactone d. Bed rest induces diuresis by the release of ANP, and decreases produciton of ADH e. Physical assessment focused on pertinent symptoms f. Give IVFs slowly to the elderly and very young and clients with a history of heart or kidney problems (high risk for FVE on IV fluids)
