Flashcards in Fluids and Electrolytes Deck (93)
we are ___% water
What portion is intracellular and what portion is extracellular?
what portion of ECF is plasma and what portion is interstitial?
what do you need to consider when managing a patients fluid status?
Evaporative Losses and “Third Spacing”
what are the two main patient types that you would not want to fluid overload?
1. renal patient who is dialysis-dependent, because their kidneys do not filter the excess fluid.
2. patients with CHF with fluids, because the more preload their hearts have, the less they can respond by increasing contractility and they can end up in cardiogenic pulmonary edema.
4 mL/kg/hr for 1st 10kg
2 mL/kg/hr for 2nd 10kg
1 mL/kg/hr for remaining kg
what is the additional fluid requirement for minimal, moderate and severe tissue trauma?
describe "third spacing"
This refers to an internal redistribution of fluids, especially during large thoracic or abdominal procedures. Intravascular fluid volume is depleted as inflamed tissue sequesters much fluid in the interstitial space. Replacement of this fluid is necessary to avoid organ hypoperfusion, especially in renal insufficiency.
what are the advantages and disadvantages of crystalloids?
Advantages: safe, nontoxic, reaction free, and cheap.
Disadvantages: limited time in IV space, edema with large volumes.
Solutions of inorganic and small organic molecules dissolved in water. The main solute is saline or glucose and the solution may be iso, hypo, or hypertonic.
in terms of acid-base balance, what can NS and LR cause?
Saline solution --> Hyperchloremic metabolic acidosis
Lactated Ringer’s--> Metabolic alkalosis (lactate--> HCO3)
what ion in which crystalloid limits its use when transfusing blood products?
Calcium in LR
Why is NS used in neuro cases?
pulls fluid out of the tissue, making a clearer visual field for the surgeon
Homogeneous noncrystalline substance consisting of large molecules dissolved in a solute. Most are dissolved in normal saline, but glucose, hypertonic saline, and LR have been used as well
advantages of colloids
Greater capacity to remain in the IV space (longer half life), more efficient for replacing a severe fluid deficit quickly, smaller infused volume.
disadvantages of colloids
greater expense, coagulopathy, hypersensitivity reactions
what is the difference between hextend and hespand?
Hextend = hetastarch in LR
Hespan = hetastarch in NS
Albumin is purified from _________
______ can lead to a reduction in factor VIII and vWf, impairs plt function, and can prolong PTT.
how does dextran 40 improve microcirculation blood flow?
by decreasing blood viscosity and is often used by vascular and plastic surgeons to maintain patency of anastamoses.
_________ decreases platelet aggregation and adhesiveness.
dextran (mostly 70)
what portion of colloids is distributed intracellularly and extracellularly?
what is a mEq?
A milliequivalent is defined as 1/1000 of an equivalent of a chemical element, radical or compound. Its abbreviation is "mEq." The equation used to calculate a milliequivalent is atomic weight (g) / (valence x 1000). The unit of measure for mEq is grams (g).
what are some normal hematology lab values?
White Blood Cell Count (WBC)(cells/ml): 4,500-10,000
Red Blood Cell Count (RBC)(x 10 6): 4.0-5.5
Hemoglobin (Hgb)(g/dl): 12.0-16.5
Hematocrit (Hct)(%): 36-50
Mean Corpuscular Volume (MCV): 80-100
Platelet Count (plt): 100,000-450,000
what are some normal plasma values for electrolytes?
Sodium (Na+)( mEq/L): 135-145
Potassium (K+)(mEq/L): 3.5-5.0
Chloride (Cl-)(mEq/L): 100-106
Calcium (Ca++)(mEq/L): 8.5-10
Bicarbonate (HCO3-) (mEq/L) 22-26
Magnesium (Mg++)(mEq/L): 1.5-2.5
Phosphate (PO4---)(mEq/L): 0.5-1.5
Sulfate (SO4--)(mEq/L): 0.3-0.6
what are some normal values for coagulation studies?
Protime (PT)(Extrinsic pathway): 10-14 seconds
Partial Prothrombin Time (PTT)(Intrinsic pathway): 25-39 sec
International Normalized Ratio (INR): 0.8-1.2
INR= PT test/PT normal
_______ is the key regulator of water balance in the body
_______ is the most abundant cation of the ECF and is critical in determining EC and IC osmolarity.
_______ is the most abundant anion of the ECF