Fluid Therapy Flashcards
why is hypovolemia a problem?
decreased organ perfusion
ischemia
multi-organ failure
why is hypervolemia a problem?
organ dysfunction
impaired healing
what are insensible losses estimated to be?
22ml/kg/day
what are insensible losses?
immeasurable
respiratory tract and skin
what is hydration?
measure of interstitial fluid content
how can you asses dehydration/hydration?
skin turgor
moisture of mucous membranes
enophthalmos?
+/- tachycardia and collapse if severe
what is volume status?
measure of tissue perfusion
what are the etiologies of hypovolemic shock?
hemorrhage
massive fluid losses
what is cardiogenic shock?
diminished cardiac output due to decreased systolic function
what do you need to do if a patient is dehydrated?
replace interstitial deficits
what do you need to do if a patient is in shock?
improve perfusion
when should you consider protein losing nephropathy in a dehydrated dog?
azotemic
TS <5.5
how much weight gain does fluid overload produce?
> 10% from non-dehydrated baseline
what are some obvious signs of fluid overload?
peripheral edema
respiratory compromise
body cavity effusion
why is sodium and water retention a protective mechanism during critical illness and surgery?
maintaining effective circulatory volume
mitigates the systemic effects of hypovolemia
what can cause impaired excretion of water and be a risk factor for fluid overload?
heart, kidney, or liver disease
increased vasopressin release
what are the crystalloid fluids?
isotonic
hypotonic
hypertonic
what is a crystalloid?
electrolyte solution with molecules that move across semipermeable membranes
what are some hypotonic fluids?
0.45% saline
plyte-56
D5W
what are some indications for hypertonic saline?
shock treatment
head trauma
what are colloids?
solutions with molecules that are not easily able to move out of the vascular space
what can albumin be used to treat?
significant hypoalbuminemia
what can plasma be used to treat?
oncotic support when albumin transfusion is not available
replacement of clotting factors
when can SQ fluids be useful?
small deficits
smaller patients
what should your fluid therapy plan address?
dehydration
daily maintenance requirements
ongoing losses
what is the maintenance fluid rate usually used for cats?
45 ml/kg/day
what is the water content of pediatrics compared to adults?
higher water content: 80%
what rate should you not exceed with potassium supplementation?
0.5 mEq/kg/h
what is dextrose supplementation frequently needed for?
hypoglycemia
neonates
certain toxins
what are the starting anesthesia fluid rates for dogs and cats?
dogs: 5 ml/kg/hr
cats: 3 ml/kg/hr
what is the total intravascular fluid volume (shock dose) for dogs and cats?
dogs: 90 ml/kg
cats: 60 ml/kg
what determines movement of body water?
hydrostatic
oncotic
osmotic
what makes up “maintenance” requirement?
sensible losses: urine/feces
insensible: respiratory tract and skin
what is shock?
decreased delivery of oxygen to tissues
how can you assess shock?
heart rate
capillary refill time
mucous membrane color
blood pressure
what are the types of shock?
hypovolemic
septic
cardiac
what compensatory mechanisms are at play in shock to maintain blood pressure and cerebral perfusion?
increased heart rate
increased stroke volume
increased vascular tone
what is the etiology of septic shock?
endotoxin release into systemic circulation
trigger inflammatory mediators
loss of vascular tone
what are the etiologies of cardiogenic shock?
dilated cardiomyopathies
pericardial effusion
arrhythmias
myocarditis
what should you do if you assess a patient to be in shock?
10-20 ml/kg IV
consider second bolus if indicated
add blood if indicated
what is a useful sign of hypervolemia?
weight gain
why does water retention occur with critical illness and surgery?
sodium and water retention is a protective mechanism: circulatory volume and mitigate hypovolemia effects
vasopressin release and activation of RAAS
what are the risk factors for development of fluid overload?
impaired excretion of water
abnormal function of the interstitial compartment
how does ischemia/reperfusion injury contribute to development of fluid overload in critical illness?
increased capillary permeability
what are the four Ds of fluid prescription?
drug
dosing
duration
de-escalation
if you’re giving replacement fluids, what should you give?
isotonic fluids: crystalloids
what does it mean that a fluid is balanced?
contain buffer: more physiologic
what are some indications for hypotonic fluids?
maintenance fluid therapy
patients with dehydration and fluid intolerance
treatment of hypernatremia
can you use hypertonic saline in an animal that is dehydrated?
no
what does giving hypertonic saline too fast cause?
reflex bradycardia
is plasma an efficient way to increase albumin?
no
how are subcutaneous fluids dosed?
up to 20 ml/kg
how long should replacement fluids for dehydration be delivered over?
8-24 hours
48-72 hours for patients at risk for fluid overload
why are fluid requirements higher for pediatrics?
more extracellular fluid
higher water content
higher metabolic rate
immature kidneys cannot concentrate urine
what are the maintenance fluid rates for puppies and kittens?
90 ml/kg puppies
60-80 ml/kg kittens
what rate of potassium supplementation should you not exceed?
0.5 mEq/kg/hr without attentive patient monitoring
