Flashcards
Fluid Balance, Electrolytes, and pH
Flashcards do conjunto (42)
- 1OsmosisWater moves from a chamber of low solute concentration to one of high solute concentration to establish equilibrium
- 2FiltrationMovement of fluid through cell or blood vessel membrane because of differences in water volume pressing against confining walls (hydrostatic pressure)
- 3DiffusionFree movement of particles (solute) across permeable membrane from area of higher to lower concentration - Important in transport of most electrolytes; other particles diffuse through cell membranes
- 4Hydrostatic Pressure“Water-pushing pressure”
Force that pushes water outward from a confined space through a membrane - 5What sign develops with changes in normal hydrostatic pressure?Edema
- 6What are the sensible (measurable) means through which fluid is lost?Kidneys, wound drains, GI tract
- 7What are the insensible (immeasurable) means through which fluid is lost?Lungs (respiration) and skin (evaporation, perspiration)
- 8Fluid loss can be increased during a hypermetabolic state. What is a hypermetabolic state?An abnormally increased rate of metabolism such as a fever, burn, trauma, thyroid crisis, and tachypnea.
- 9What is the minimum urine amount needed to excrete toxic waste products?400 to 600 mL
- 10What role does ADH play in regulating Na+ and water balance?ADH (antidiuretic hormone) from the posterior pituitary acts on the kidney to promote water reabsorption, thus preventing its loss in the urine
- 11What role does aldosterone play in regulating Na+ and water balance?↓BP (↓blood volume) causes kidneys to secrete renin – activates angiotensinogen (angiotensin I) – angiotensin converting enzyme activates angiotensin II – vasoconstriction – causes adrenal gland to secrete Aldosterone which acts on the kidney to promote sodium reabsorption, thus preventing its loss in the urine
- 12What role does ANH play in regulating Na+ and water balance?ANH (atrial natriuretic hormone) from the atrium of the heart acts on the kidney to promote sodium excretion so that it is excreted in the urine
- 13Which pathway is greatly stimulated with shock, or when stress response is stimulated?Renin-angiotensin II. This is why urine output is used as an indicator of perfusion adequacy after surgery or any time the patient has undergone an invasive procedure.
- 14What is hypovolemic shock?Vital organ hypoxia/anoxia
- 15If a patient is dehydrated but incontinent and a fall risk, is it appropriate to let them decrease their fluid intake before bed?No. They need to continue to increase their fluids.
- 16When a patient is receiving IV therapy for dehydration, what things do you need to be monitoring for?Pulse quality, urine output, weight (every 8 hours), IV site, and fluid overload (bounding pulse, difficult breathing, JVD in upright position, edema)
- 17What are the common causes of fluid overload?Excess fluid replacement, kidney failure (late stage), heart failure, long term corticosteroid use, SIADH, psych disorders w/ polydipsia, interstitial to plasma fluid shifts (burns, excess Na+ intake)
- 18Severe hypervolemia can lead to...pulmonary edema and heart failure.
- 19If your patient has fluid overload, what position should they be placed in?Semi-Fowler's
- 20mannitol (Osmitrol) is an example of what kind of diuretic?Osmotic diuretic
- 21Which drugs are - rarely used in the management of HTN d/t short duration of action & availability of better drugs?Loop diuretics like Lasix
- 22Besides ototoxicity and potasium depletion, what is another possible adverse effect of Lasix?Precipitation of gout by means of blocking renal excretion of uric acid
- 23What is the primary use of mannitol (Osmitrol)?decrease intracranial pressure (it is not metabolized so it is freely filtered at the glomerulus)
- 24What is one of the most common causes of hyponatremia?Prolonged use/overuse of diuretics
- 25What does isotonic mean?When the concentration of dissolved particles is similar to that of plasma. Isotonic solutions have an osmolality of 250 to 375 mOsm/L.
- 26Which solution is the most physiologically adaptable fluid?Lactated Ringer's Solution
- 27What does D5W do?-Rapidly metabolized by the body.
-Provides free unbound water molecules (can pass into cells providing hydration, provides free water to the kidneys which aids renal excretion of solutes)
-Treats hypernatremia - 28What is the net result when dextrose is added to isotonic or hypotonic solutions?a slightly hypertonic solution
- 29What are some examples of pH buffers?-bicarbonate and phosphate together
-proteins (albumin, globulin, hemoglobulin) - 30When cells metabolize glucose under anaerobic conditions, this produces...lactic acid
- 31Where does bicarbonate come from?Ingestion and pancreatic production
- 32How do kidneys control acid-base mechanisms?movement of bicarbonate- either excrete it or reabsorb depending on level of H+
- 33How does ammonium effect acid-base levels?secreted in urine, traps excess H+, both are excreted
- 34When referring to the kidney's role in pH regulation, what does full compensation mean?If the pH is brought back to normal range
- 35When the kidneys bring the pH almost back to a normal range, this is referred to as...partial compensation.
- 36When looking at lab values for respiratory and metabolic pH, which is inversely proportional?Respiratory
- 37What is combined metabolic and respiratory acidosis?Uncorrected respiratory acidosis leads to poor oxygenation and lactic acidosis
- 38Who is at risk for combined respiratory and metabolic acidosis?Combined problem of Diabetic Ketoacidosis (DKA) and COPD
- 39What are some S/S of acidosis?-Creates imbalance with positive ions – especially K
-Disrupts function nerves, cardiac/skeletal muscles(early s/s)
-Reduces excitability of membranes
-CNS changes; lethargy, confusion to coma
-Neuromuscular changes – behavioral changes seen early
-↓ muscle tone, deep tendon reflexes - 40What is the hallmark of respiratory acidosis?Decreased pH, PaO2 with rising PaCO2
- 41What is the hallmark of base excess acidosis?ABG result with ↑ pH and ↑ bicarbonate level with normal O2 and CO2 levels
- 42What is the hallmark of respiratory alkalosis?-ABG result with ↑ pH coupled with low CO2 level
-O2 and bicarbonate usually normal