5a Flashcards
Body fluid composition
Water makes up 60% of weightIntracellular water–40% of weight, 2/3 of total body water, high K +Extra cellular water–20% of weight, 1/3 of total body water, high Na +EC water is1. Intravascular/plasma 25%2. Extravascular/interstitial 75%
Movement of fluid within the body depends on…..
… The balance btwn 1. Filtration (incr hydrostatic P, decr oncotic P)2. Resorption (decr hydrostatic P, incr oncotic P)occurs at the level of the capillary
Define dehydration
Hypohydration= loss of bodily fluidsCauses: GI, renal, burns/skin, respiratory tract, saliva, third spacing, hemorrhage
Dehydration and PE chart
<5% non-detectable5-8% decr skin turgor, dry MM8-10% + eyes sunken, prolong CRT10-12% + severe skin tent, eyes sunken, prolong CRT, dry MM, +/- shock12% life threatening
Shock dose dog vs cat
Dog 90ml/kgCat 50 ml/kg= to one blood volume
hyper vs hypotonic fluid losses
hypotonic fluid losses (loss of water >solutes)–>tonicity of extracellular fluid incr–>water shifts from intracellular to extracellular–>intracellular dehydrationhypertonic fluid losses (loss of solutes >water)–>tonicity of intracellular fluid will be higher or hypertonic and fluid to shift from extracellular to intracellular–>extracellular dehydration
guidelines for calculating rehydration for patient
KG x % dehyd (replacement) +estimated losses + maintanence
osmolarity of plasma
290-310 mOsm/L
isotonic fluids contain which types of bicarbonate precursors
alkalinizing effect1. lactate–metabolized by liver (D-lactate is not mx)2. acetate–metabolized by muscle (more profound effect)3. gluconate–metabolized by many cells
Fluid choice for patients with hypoNa, hypoCl, metabolic alkalosis
0.9% NaCl
T/FLarge quantities of acetate containing fluids can cause vasodilation and decr in BP
trueLarge quantities of acetate containing fluids can cause vasodilation and decr in BPsecondary to adenosine release (potent vasodilator) from muscle
fluid choice for head trauma patients
0.9% NaClbecause of high Na content (154 mEq/L) and is least likely to cause decr in osmolarity and subsequent water movement into brain interstitium
replacement vs maintenance fluids
replacement—isotonic (hi NaCl)maintenance–hypotonic (low NaCl, hi K)
option to treat free water deficit
hypotonic fluid252 mOsm/L (slightly lower than plasma)5% dextrose with sterile water
fluid choice for patients with diabetes insipidus or hypernatremia
sterile water with 5% dextrose
T/FD5W can be given as a bolus
FALSEhypotonicif given as a bolus will distribute to all body fluid compartments, cause acute decreases in osmolarity and lead to cerebral edema.
Why administer hypertonic fluids slowly
if hypertonic fluids are given too fast (> 1 ml/kg/min) osmotic stimulation of pulmonary C fibers results in vagal mediated bradycardia, bronchoconstriction, hypotensionbc monocyte dehydration and subsequent friction btwn monocytes
goal of hypertonic saline solutions
draw extravascular water into the intravascular spaceosmotic diuresis
contraindications of HTS use
do not given in already dehydrated animalsphlebitis/hemolysisavoid right atrium (leads to arrhythmias)
How are synthetic colloids described
by their weight average (Mw) or number average (Mn) molecular weightpolydispersity index Mw/Mn ratiohigher molecular weight molecules are not metabolized or excreted as quickly as smaller particlespersist longer
side effects of colloid administration
disrupt normal coagulationdecr factor VIII, vWFimpair platelet fxinterfer w fibrin clot stability–>increased finbrinolysis
hydroxyethyl starch colloids are characterized by what?
contain highly branched starch, amylopectinweight average (Mw)–low, med, hiconcentration %# substitutions (more substitutions last longer)
T/F Total protein refractometer readings are a valid way of monitoring colloidal therapy
FALSEcolloids do NOT increase TP
Characteristics of oxyglobin
Hb based oxygen carrying fluidsterile, ultrapure, bovine Hb solutionnonantigenic40 mm Hg oncotic P13 ml/dL Hb concentration