# Shared Flashcard Set

## Details

Fluid therapy
Hsu
86
Pharmacology
Professional
11/04/2011

Term
 Biochemical basis of fluid therapy
Definition
 Body water concept of milliequivalents osmosis and osmolarity role in kidney in water and salt regulation acid-base regulation
Term
 Body water
Definition
 60% of BW mature animals 70-75% BW in young IC fluid=40% EC fluid=20%
Term
 Extracellular fluid
Definition
 plasma water=5% BW Interstitial fluid=15% BW transcellular fluid=1-6% BW
Term
 Body water turnover
Definition
 65 ml/kg/day   (50-70 ml/kg/day)
Term
 Concept of mEq
Definition
 Eq. wt.=mol wt./ionic valence
Term
 How to calculate mEq for monovalent ions
Definition
 moles=actual wt (g)/mol wt mmol=actual wt (mg)/mol wt 1 Eq=1 mole (1 mEq=1 mmol)   How many mg is in 1 mEq of NaCl? mw=58.5 1 mEq=1 mmol=X mg/58.5 X=58.5 mg
Term
 Calulate mEq for divalent ions
Definition
 Eq wt of CaCl2=111 mw/2=55.5 mEq CaCl2=actual wt in mg/Eq wt How many mg of CaCl2 are in 1 mEq of CaCl2? 1 mEq=x mg/Eq wt=x mg/55.5 x=55.5 mg
Term
 Concept of mEq
Definition
 most electrolyte concentrations of plasma are expressed as mEq/L Total plasma concentraion of cationsin mEq/L must be equal to that of anions to maintain electroneutrality Plasma calcium and phosphorus concentrations are usually measured as mg% or mM
Term
 Osmosis
Definition
 Fluid compartments are separated by semipermeable membranes allow free passage of water but restrict particles water moves toward compartment with higher number of particles
Term
 Osmolarity
Definition
 describe properties related to number of particles in solution mOsm/L
Term
 Tonicity: osmotic pressure relative to plasma
Definition
 isotonic solution=300 mOsm/L isotonic solution of NaCl in mM=150 mOsm/L isotonic solution of glucose in mM=300 mOsm/L isotonic solution of Na lactate in mM=150 mOsm/L
Term
 Molarity calculation
Definition
 mM=wt (mg)/mol. wt x 1000/V (ml)   M=mol/L mM=mmol/L
Term
 Institution of therapy
Definition
 Main purpose is to correct dehydration and/or electrolytes imbalances   use fluids correct acid-base disturbances and K+ imbalances Routes of administration Products for fluid therapy
Term
 conditions under which fluid therapy is needed
Definition
 dehydration acid-base disturbances and/or electrolytes imbalances nutrional problems loss of body fluids, esp plasma
Term
 Dehydration and electrolyte imbalances
Definition
 causes and treatment-amount to be used role of electrolytes on water and acid-base balances role of intermediary metabolism on hydration and acid-base balances basis for fluid therapy institution:accurate diagnosis
Term
 Type of dehydration
Definition
 Hypertonic   isotonic   hypotonic
Term
 Causes of hypertonic dehydration
Definition
 Lack of intake: 1. lack of water source 2. disorders of buccal cavity, pharynx 3. CNS disturbances; paralysis   Respiratory loss of water leads to hypertonic dehydration
Term
 Cause of isotonic/hypotonic dehydration
Definition
 polyuria: diabetes, nephrosis, hypoadrenocorticism, diuretics, large wounds profuse sweating in horses vomiting/diarrhea Third space loss: fluid retained in a cavity
Term
 Dehydration treatment   iso/hypotonic
Definition
 administer fluid with or without electrolytes   treatment of third space loss
Term
 Electrolytes on water and acid-base balances
Definition
 increased Na+ in ECF-> water retention   Changes in [K+] result in changes in acid-base balance   Changes in [H+] result in changes in [K+]
Term
 Acidemia and K
Definition
 -increased K+ in plasma->increased K+, decreased H+ in urine   acidemia->hyperkalemia
Term
 Alkalemia and K
Definition
 decreased K+ in plasma   Alkalemia leads to hypokalemia
Term
 role of intermediary metabolism
Definition
 increased CHO intake or decreased utilization->hyperglycemia->glucosuria->polyuria->dehydration   increased CHO intake (grain overload)->increased lactic acid->acidosis   decreased CHO utilization-> increased gluconeogenesis->ketoacidosis
Term
 Amount of fluid to be used   based on:
Definition
 body water maintenance (sensible loss+ insensible loss)   replacement of deficit   replacement of ongoing loss
Term
 Amount of body water for maintenance
Definition
 Body water turnover: 50-70 ml/kg/d Average 65 ml/kg/d
Term
 4% dehydration
Definition
 based on body weight   mild a history of fluid loss, but no significant signs of dehydration no replacement needed
Term
 6% dehydration
Definition
 moderate leathery skin dogs, cats, calves, foals when skin is pinched into a tented fold->peaks->slowly return to normal in larger species pinch neck or dorsal eyelid decrease skin elasticity also seen in aging, cachexia obese patients dull haircoat dry mucous membranes can be caused by open-mouth breathing
Term
 8-10% dehydration
Definition
 severe skin lacks pliability in dogs and cats skin pinch->peaks and STAY dry mucous membranes and tongue soft, sunken eyeballs into orbit (enophthalmus) cold limbs capillary refill time >3 s (normal <2s)
Term
 12 % dehydration
Definition
 extremely severe all signs seen with 8-10% dehydration circulatory collapse-shock
Term
 Determination of replacement volume (L)
Definition
 % dehydration x body weight (KG)       Replacement volume for 10 kg dog with 10% dehydration=1 L   One kg of water=1 L
Term
 Determining fluid replacement first 24 hours
Definition
 A=Maintenance dose= chart ml for weight given   B=Deficit=wt (kg) x % dehydration   C=ongoing loss   Fluid replacement=A+B+C L or ml   After 24 hours->Reassess
Term
 Dehydration treatment
Definition
 Fluid volume to be used is considered estimate   Adjustment based on reassessment is needed
Term
 Dehydration factors
Definition
 effects young animals much faster and more severe   old patients or patients with a chronic disease may require more water   physical and weather conditions may change water requirement   drugs such as corticosteroids and diuretics may change requirement
Term
 good diagnosis needed for fluid therapy   clinical signs
Definition
 accurate diagnosis based on clinical exams and lab data   for detection of dehydration, skin, buccal mucosa and eyeball conditions   signs of vomiting? diarrhea? polyuria? abnormal respiration? CNS depression (acidotic) or excitation (alkalotic)?   Blood electrolytes, gas and urine analyses important
Term
 Therapy for Metabolic Acidosis   Direct agents
Definition
 Alkalinizing agents neutralize proton NaHCO3 THAM (tris; tromethamine)-irritation
Term
 Therapy for metabolic acidosis   Indirect agents
Definition
 metabolized into sodium bicarb to neutralize proton Na lactate-Lactated Ringer's Na acetate-Acetated Polyionic Na gluconate Na citrate-may induce vomiting
Term
Definition
 Short shelf-life in solution: 2 years at 4 C Can't be autoclaved 2NaHCO3->Na2CO3 +H2O + CO2 Oral dosing interferes with gastric acidity and milk digestion
Term
 Na Lactate as indirect agent
Definition
 Lactate->lactic acid->moved down chain of events->carbonic anhydrase to carbonic acid-> bicarb   bicarb used to neutralize
Term
 Indirect alkalinizing agents   Na lactate
Definition
 onset time following IV administration ~30 min D-lactate is minimally metabolized, L-form metabolized Other indirect agents do not have the problem with Na lactate Do not use Na lactate in patients with lactic acidosis (plasma lactate > 9 mEq/L)
Term
 Indirect alkalinizing agents   Na acetate
Definition
 Na acetate is used by muscle Doesn't have minimally metabolized form Acetate is more efficient than lactate Acetate induces vasodilation-issue if in shock Do not use Na acetate in ketoacidosis
Term
 Calculating NaHCO3 to use
Definition
 mEq NaHCO3=BW (kg) x 0.3 x BD   if BD unkown use NaHCO3/indirect agent at 1-2 mEq/kg   difficult to over-alkalinize patient with normal renal function normal kidney can take care of chemical excess
Term
 Treatment of metabolic alkalosis
Definition
 Treat etiology Cl- responsive alkalosis: NaCl, KCl+NaCl, Ringers, NH4Cl+NaCl Cl- resistant alkalosis: Spironolactone H2-antihistamines or omeprazole (Prilosec) to stop H+ loss in GI tract
Term
 NaCl treatment for alkalosis
Definition
 Normal renal function: reabsorption in distal tubule: Cl- > HCO3-   Supply large volume normal saline->more Cl than HCO3 reabsorbed->increase plasma [Cl-], decrease plasma [HCO3-]
Term
 Ammonium Chloride for tx of alkalosis
Definition
 NH4Cl->NH3 + HCl (don't want this) 2NH4Cl + CO2 <-> CO(NH2)2 + H2O + 2HCl   NH4Cl for cattle from Univ. Georgia 54 g NH4Cl + 40 g KCL in 500 ml H2O and autoclave-> dilute with 10L of 0.9% NaCl   Don't use in liver disorders, urea poisoning
Term
 Treatment of respiratory acidosis
Definition
 proper ventilation treat etiology alkalinizing agents are optional->used if ventilation alone can't do the job (ex: pulmonary obstruction)
Term
 Treatment of respiratory alkalosis
Definition
 Treat etiology-hyperventilation Sedatives to reduce excitation and hyperventilation Acidifying agents optional
Term
 Clinical case acid-base
Definition
 mixed acid-base imbalances occur more frequently than simple ones, because of compensations Treatment may convery one type to another If pH <7.2 or >7.6 then must correct If status unclear->give Ringer's -have NaCl, KCl, CaCl so components can treat both
Term
 Combined acidosis treatment
Definition
 treat respiratory acidosis first   use alkalinizing agent next
Term
 Hypokalemia   causes
Definition
 decreased intake loss via GI tract Ex: vomiting, severe salivation, diarrhea increased aldosterone diuretics
Term
 Hypokalemia   Signs
Definition
 weak skeletal muscle contractions cardiac arrhythmias: due to increase intracellular [Ca2+] and other things 1. increased amplitude of QRS and P wave 2. Prolongation of QT interval 3. Depressed ST segment and flattened T waves
Term
 Hypokalemia   Therapy
Definition
 lab data similar to metabolic alkalosis   only tx for severe acute hypokalemia (<2.5 mEq/L) or chronic hypokalemia KCl, K gluconate or K citrate PO, SC, IV (<0.5 mEq/kg/h) Monitor signs of hyperkalemia   Hypokalemia+Digitalis=severe cardiac arrhythmias
Term
 Hyperkalemia   Causes
Definition
 decreased urinary excretion acidosis diabetes mellitus Addison's disease excessive cell damage increased intake
Term
 Hyperkalemia   Signs
Definition
 increased neuromuscular excitability   Skeletal muscle twitching, irritability, muscle weakness   Cardiac disturbances
Term
 Hyperkalemia ECG
Definition
 decreased amplitude or disappearance of P waves decreased amplitude of R waves intraventricular conduction blocks widened QRS interval, QT interval High peaked T waves Hsu hypothesis: cardiac disturbances largely due to decreased myocardial [Ca2+] intracellularly
Term
 Hyperkalemia   therapy
Definition
 lab data similar to metabolic acidosis   Ca gluconate administration Cation-exchange resin, PO Peritoneal dialysis Diuretics administration NaHCO3 (1-2 mEq/kg) Dextrose to effect or insulin for diabetes
Term
Definition
 Oral whenever possible   IV: 5% dextrose continuous for a few days in bovine fatty liver/ketosis treatment   SC routes High K+ solutions (>30 mEq/L) may be given Do not give 5% dextrose SC->too much fluid can give if animal is hypertonic and needs maintenance or off feed to improve hydration status
Term
 Rectal route
Definition
 for shock   FRVR-fluid replacement via the rectum viable alternative for fluid resuscitation in hypovolemic shock may be useful with IV not feasible Disadvantage" erratic absorption rate Contraindication in animals with diarrhea
Term
 PBS for acid-base
Definition
 used commonly in vitro contains 10 mM phosphate plasma contains ~ 0.5 mM phosphase Would bind Ca and create hypocalcemia
Term
 Rate of IV infusion
Definition
 Normal heart, lung, kidneys=90 ml/kg/h   Faster rate with acute condition slow rate with chronic condition   Recommended rate: 15 ml/kg/h in most chronic conditions
Term
 Rate of IV infusion   side effects
Definition
 rapid infusion may cause 1. vagal stimulation 2. pulmonary edema Monitor central venous pressure (CVP) 1. Normal CVP (0-3 cm of water) 2. Suspend if CVP >3cm of water   May be determental to patients with CHF or acute renal failure
Term
 Rate of infusion   glucose
Definition
 rapid infusion of glucose (>4 mg/kg/min)->hyperglycemia   Slow down infusion after 1st hour-particularly if anuria After 4 h of anuria->2 ml/kg/h   Don't use K+ or Ca2+ for rapid infusion->effect on heart
Term
 Colloids
Definition
 plasma expanders that exert colloid osmotic pressure (COP) so body water would not easily diffuse into interstitial tissue natural and synthetic
Term
 Crystalloids   Maintenance solutions
Definition
 Do not exert COP   replacement solution or dilute an electrolytes solution using 5% dextrose/water (1:1) + 11-16 mEq/L KCl used in liver disease
Term
 Hypertonic solutions
Definition
 draw body water from interstitial tissue into capillaries
Term
 Crystalloids   other solutions
Definition
 5% and 50% dextrose 7.2% NaCl 8.4% (1 M) NaHCO3 14.9% (2 M) KCl 10-40 mEq/L KCl 2M Na acetate 5M Na lactate
Term
 Synthetic colloids   plasma expanders
Definition
 Fluid (1L)       Plasma Vol Expansion (L)          Duration (hr) L. Ringer's                  0.194                                  2 6% hetastarch            0.710                                24-36      (Hespan) 6% dextran 70            0.800                                 24     (RescueFlow) 10% dextran 40          1.000                                 4-6     (Rheomacrodex)
Term
 Synthetic colloid infusion   dosages and rates
Definition
 Acute condition:10-40 ml/kg IV bolus to effect->constant-rate infusion (CRI)->maintain MAP 80 mmHg Acute cats: <20 ml/kg at slow rate (10-20 min) followed by CRI (careful with allergic response, watch for hypersensitivity) Chronic: use CRI to maintain 80 mmHg
Term
Definition
 Volume expansion: may dilute blood constituents Rapid volume expansion: detrimental to patient with acute renal failure or CHF Dextran 40 may cause acute renal failure Ag-Ab reactions (except homologous plasma)-inject slowly in cats Dextrans and hetastarch may interfere with fibrin clot formation
Term
 Hypertonic Solution   (7.2% NaCl)
Definition
 Resuscitation of animals suffering from shock; large burns; tx of injury "Small-volume resuscitation"-draw water from interstitial tissue to circulation Decreased afterload due to vasodilation-Baroreceptor reflex Increased O2 delivered to the heart
Term
 Hypertonic solution   combo with colloids
Definition
 7.2% NaCl + 6% dextran 70 or hetastarch (4-8 ml/kg)
Term
Definition
 Volume overload Edema   Patients hypernatremia or coagulation problems
Term
 Parental nutrition
Definition
 in animals who can't voluntarily consume food   prevent malnutrition or treat malnourished animals   average treatment 3-4 days   risk/benefit ratio before prolonged treatment
Term
 Total parental nutrition (TPN)
Definition
 IV infusion of glucose, amino acids, lipid, minerals, vitamins
Term
 Partial parental nutrion (PPN)
Definition
 PN + enteral nutrition
Term
 Total nutritional therapy
Definition
 infusion into a large bore vein -hypertonic solution ~1000 mOsm/L   continuous 24 h infusion   Problems: infection, expenses, care
Term
 Total Nutritional Therapy   Calories
Definition
 Glucose, fructose, invertose=4 Kcal/gm   Lipid=9 Kcal/gm   Glucose in 50% dextrose sol=50 g dextrose/100 ml H2O 1 g water=1 mL
Term
 Total nutritional therapy   Calories->math example
Definition
 20 kg dog treated with glucose to meet daily requirement How much 50% dextrose? dog needs 1100 Kcal to meet daily requirement   1100Kcal/4 Kcal/gm=275 gm glucose 275 g/ 50 g/100 ml=550 ml
Term
 Nutritional therapy   Lipid
Definition
 Lipid emulsions used as energy and EFA's provider Used for prolonged PN
Term
 Nutritional therapy   Lipid   Preparations and dosage
Definition
 soybean oil/safflower oil egg yolk phospholipids glycerin mixed with water   <2 g/kg/d
Term
Definition
 High dosages cause 1. dysfunction of granulocytes, macrophages 2. phospholipids->increased eicosanoids->inflammation
Term
 Nutritional therapy   Lipid   Contraindication
Definition
 Patients with high triglyceride levels   esp. hereditary hyperlipidemia
Term
 Nutritional therapy   Amino acids   general
Definition
 to induce (+) nitrogen balance and provide essential amino acids   do not use intact proteins   Aminosyn, Travasol
Term
 Nutritional therapy   Amino acids   Dosages
Definition
 40-50 mg/Kcal/d (dogs)   60 mg/Kcal/d (cats)   More in young, growing animals or hypoproteinemia, large draining wound   Reduced in patients with protein intolerance, ex: hepatic encephalopathy   provide calories concurrently
Term
 Special problems with horses
Definition
 Severe metabolic acidosis-diarrhea, shock, gut obstruction, chock Respiratory acidosis with inhalation anesthesia Severe hyponatremia associated with dehydration Severe hyperkalemia (>7 mEq/L) associated with acidosis in foals Prompt correction of acidosis usually corrects hyperkalemia
Term
 Special problems with Cattle
Definition
 Metabolic alkalosis and hypokalemia-abomasum disease   Severe metabolic acidosis and dehydration-grain overload and calf diarrhea   Severe K+ deficit in anorectic animals   Oral fluid therapy in neonatal diarrhea in suckling calf
Term
 Effects of anesthetic and surgery   Problems in all species
Definition
 1. general anesthetics: decreased CP, blood flow and GFR, increased vasodilation (Closure of Ca2+ channels)-> increased fluid requirement 2. increased fluid loss via expired air and surgery 3. third space Fluid therapy:2-5 ml/kg/h crystalloid routinely IV fluid->decreased plasma proteins and blood cell Volume overload and hypertension in post-surgical period
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