IV fluid therapy Flashcards
What is the formula for enteral/isotonic balanced electrolyte fluid therapy?
-table salt (noniodized): 14 cc
-lite salt: 2.5 cc Lite salt
-baking soda : 11 cc
-water: 4 liters of water
What is the 60-40-20 rule?
60% of total body weight is water
40% of total body weight is intracellular fluid
20% of total body weight is extracellular fluid
What is the normal osmolality made up of (280-300 mosm)
{2X (Na +K)} + (glucose/18) + (BUN/2.8)
**some sources choose to exclude potassium (b/c small) or BUN (ineffective osmole)
blood Pressure=
simple equation
flow (cardiac output) X resistance (total peripheral resistance)
Stroke volume equation
End-diastolic volume - end-systolic volume
Cardiac output equation
HR X SV
blood Pressure =
{HR x (end-diastolic volume-end systolic volume)} x total peripheral resistance
What is central venous pressure of adults and foals?
adults: 5-15 cmH2O
foals: 2-12 cm H2O
What is the equation for fractional excretion?
{(serum creatinine)/ (urine creatinine)} x {(urine electrolyte)/ (serum electrolyte)}
What is normal FE of sodium?
<1%
causes of pseudohypernatremia
hyperlipemia
hyperproteinemia
What electrolyte abnormalities are seen with a ruptured bladder?
hyponatremia
hypochloremia
hyperkalemia
peritoneal fluid crea 2x that of systemic creainine
Describe the characteristics of syndrome of inappropriate antidiuretic hormone
-increased concentrations of ADH
-decreased osmolality
-Normovolemia
-inappropriate urinary concentration
-increased urinary sodium
**r/o kidney & endocrine disorders
What is the hyponatremia correction rate?
0.5 mEq/h
What is the hourly fluid rate in adults and neonates?
adults: 2-3 ml/kg/hour
neonates: 4-6 ml/kg/hour (double that of adults)
When on fluids, what should be the urine production rate?
urine production should be half of the fluid rate
What is the dextrose CRI rate?
adult: 1-2 mg/kg/min
neonates: 4-8 mg/kg/min
what is the osmolarity of hypertonic saline (7.2% NaCl)?
2462 mOsm/L
what is the dose of hypertonic saline?
4-5 ml/kg IV once
What are the advantages of hypertonic saline?
-volume expansion (increases plasma volume 3-4x the volume administered)
-anti-edema
-immunomodulation & anti-inflammatory
-anti-apoptosis
-free radical scavenge
-inhibition of leukoactivation
-prevention of immunosuppression
-positive inotrope by improving (INC end-diastolic volume, leading to inc stroke volume and inc CO— effect lasts 1 hour following infusion)
How much is a shock bolus?
60-90 ml/kg IV once
*dividing equally into three separate doses (ie: 20 ml/kg three times)
*stop when you see PINK-PERK-PEE
What are doses of hetastarch?
2-10 ml/kg IV once
What are contraindications for hetastarch administration?
renal disease
coagulopathies
For any electrolyte correction, what is the quation?
mEq to be infused = volume of distribution X body weight (kg) X deficit
What is the volume of distribution in foals vs adults?
foals: 60%= 0.6
adults: 30% =0.3
For neonates, what is the goal to which to restore the sodium level if hyponatremic?
125 mmol/L
**calculated amount of sodium required in first 6 hours to raise sodium level to 125 mmol/L
what is the maximum rate for sodium administration?
0.5 mEq/kg/hour
1 gram of baking soda has how much HCO3
12 mEq
isotonic bicarbonate is what osmolarity?
150 mmol/L
organic acidosis is due to
hyperlactatemia
inorganic acidosis is due to
hyperchloremia (or hyponatremia)
What are electrolyte abnormalities that worsen or potentiate hepatic encephalopathy?
-alkalosis
-hypokalemia
What fluids should be avoided in liver disease & why?
lactated fluids– since the lactate is the buffer solution & its conversion to bicarbonate in the liver is required
(ie: LRS will become acidifying solution the face of liver dz d/t the inability to convert lactate to bicabronate)
Which form of ammonium/ammonia can/cannot cross the blood brain barrier?
Ammonium (NH4) cannot cross the blood brain barrier
**longer word, pos charge molecules cannot cross BBB)
Ammonia (NH3) can cross the blood brain barrier
Describe why hypokalemia worsens hepatic encephalopathy?
–potassium will displace from inside the cell
–H will then be displaced to maintain electroneutrality (inside the cell)
– And excreted into urine, H will be exchanged for ammonia in the renal tubules
What are example of acetated/gluconated fluids to be administered in liver disease?
–Normosol-R
–Plasma-Lyte
The anion gap equation is calculated to estimate
the accumulation of unmeasured anions as strong acids are produced
What are examples of unmeasured anions
lactate, ketoacids, sulfates, toxins, salicylates, methanol, ethylene glycol
What is the anion gap equation?
AG = (Na + K) - (Cl + HCO3) = ~18 mEq
rr: 9-19 mEq
What are reasons for an increased anion gap?
** an increase in unmeasured anions
What is the equation for strong ion difference?
SID = (Na + K) - (Cl + lactate) = 40
What is the equation for strong ion gap (SIG)?
SIG= UC-UA = 0
SIDe= {(Na + K +iCa + iMg) - (Cl + lactate)} - (HCO3 + (2.25 x Albumin) + (1.4 x globulins) + (0.59 x P04)} = 0
Define type A lactic acidosis
hyperlactatemia d/t tissue hypoxia
**hypoxemia, hypoperfusion, anemia
Define type B lactic acidosis
hyperlactatemia in the absence to tissue hypoxia
–sepsis, inflammation, thiamine deficiency, catabolism, beta2 adrenergic stimulation, inc mm activity (esp with seizures)
lactate clearance is performed by what organs (primary, secondary, tertiary)?
primary: liver
secondary: kidney (metabolism, not excretion)
tertiary: heart, skeletal mm
sodium bicarbonate should not be administered with what conditions?
-lactic acidosis (will serve no purpose to correct the acidemia)
-pulmonary disease (unable to “blow off” to bicarbonate)
-unmeasured anion acidosis
To replace blood loss with crystalloid solution, what volume is required?
3 to 4 times the volume of blood lost needs to be replaced
What are pathologic changes that lead to changes in hydrostatic pressure?
heart failure (R or L)
thromboses
IVF
diuretic administration
acute blood loss
degeneration of interstitial collagen
inflammatory cytokines
severe burns
Tonicity of extracellular fluid volume is regulated by?
antidiuretic hormone
Rapid correction of hypovolemia occurs with reversal of the 7 perfusion parameters. what are these?
-tachycardia
-pale mm
-prolonged CRT
-cold extremities
-poor pulse quality
-depressed mentation
-reduced jugular fill
What are signs of intravascular volume overload?
-INC CVP (>10-20 cmH20 neonates- 15 cmH20 adults)
-DEC PaO2 likely secondary to pulmonary edema
-DEC spO2 consistent with pulmonary edema development
-CS: SQ edema, tachypnea, edema large airways-nostrils
If there is no improvement in hypoperfusion, it is not only due to hypovolemia , what treatments are recommended?
-requires inotropes +/- vasopressors
central venous pressure is determined by
blood volume
venous tone
cardiac contractility
What are values for fluid therapy monitoring techniques?
CVP
MAP
lactate concen
CO
glucose
urina anlytes
foals direct and indirect MAP should be
direct MAP ~85 mmHg
indirect MAP ~ 144 mmHg
adults direct MAP normal
110-133 mmHG
at what MAP does end organ perfusion occur
60 mmHg
What is the rate of dextrose supplementation in the cases of liver dysfunction/failure
0.5 mg/kg/min
**up to 1-2 mg/kg/min
Why is it recommended to supplement dextrose in liver cases?
even if normoglycemic– will limit gluconeogenesis, catabolism of tissues & risk of hyperammoniogenesis
Isotonic fluids are preferred in renal failure, what are best choices?
-normosol & plasmalyte excellent (potassium)
-isotonic sodium bicarb
-LRS preferred over saline but hyperchloremic acidosis
calves with 2 to 4 % dehydration
– <2 mm eye ball recession (mm)
– 3 to 4 seconds skin tent
calves with 6-8% dehydration
3-4 mm eye ball recession
5 to 6 seconds skin tent
calves with 10 -14% dehydration
6-8 mm eye ball recession
7 to 9 second skin tent
Most sick cattle have which acid base abnormality
alkalotic
Most sick cattle are alkalotic, however what are conditions in cattle where acidosis are more common?
-urinary tract disease
-grain overload
-small intestinal strangulation/ obstruction
-enteritis/diarrhea
In cattle, the hypertonic saline when administered with what, is effective in rehydrating cattle ?
combined with oral electrolyte solutions
What diseases in cattle, is dextrose administration recommended?
early lactation with severe ketosis, hepatic lipidosis, hypoglycemia
A positive base excess , is what abnormality?
alkalosis
A negative base excess (base deficit), is what abnormality
acidosis
When correcting a metabolic acidosis, how much of the deficit should you replace?
replace half of deficit, then re-evaluate
–inc renal perfusion
–inc tissue perfusion
How many mEq of HCO3 are in baking soda?
12 mEq per gram of baking soda
what is isotonic bicarb
1.3% bicarb
154 mEq/L
How to make isotonic bicarb?
isotonic bicarb= 1.3% bicarb, 154 mEq/L
12 mEq baking soda / 1 gram
154 mEq/12 mE/gram baking soda= 13 grams baking soda per liter
for treatment of hypernatremia, the sodium concentration should drop at what rate?
1 mEq/hour drop in Na concentration
