Intravenous Fluids Flashcards
Outline the basics of the Frank-Staling curve
there is an optimal ratio of stroke volume to preload. Adequate preload restulsin lower PPV or SVV variability. hypervolemic patients may need to be de-resuscitated to stop the fluid overload, which also isn’t good.
inadequate preload resuls in greater PPB or SVV variability . hypovolemic patients may need to be resuscitated
4 specific goals of IV fluid prescription
- rescue
- optimiazation
- stabilization
- de-escalation
rescue goal
- Rescue
- Life-saving therapy for unstable patients with large volume deficits
- E.g. life-threatening hemorrhage, septic shock
optimization IV fluid goal
Optimization
• Organ rescue for potentially unstable patients with major threats to volume status
• E.g. diabetic ketoacidosis, severe burn
stabilization goal of IV fldui
• Stabilization
• Organ support for stable patients close to steady state, but unable to maintain their own
volume status • E.g. post-operative patient that is NPO
All types of IV fluid goals (rescue, optimization, stabilization, deescalation) use parameters such as BP, HR, lactate, blood gases, and cap refil to assess success.
What goal uses altered mental status as a parameter?
what goals use urine output and fluid balance as a parameter
altered mental status: rescue goal
urine output and fluid balance: optimiazation, stabilization, de-escalation.
outline the goal of fluid precriptoin based on the case:
- stable pulmonary embolism
- gallstone pancreatitis
- massive upper GI bleed
- stabilization- maintain steady state
- optimization– prevent organ failure
- resuce– save her life!
typical proportions of water in med, women, elderly and children
how is the water distributed in the body compartments?
- extracellular (33%)– intravascular (25%), and interstitial (75%)
- intracellular (67%)
- varies with age
net fluid movement at steady state;
intravascular–>interstitial: depends on __ ___ and ___ function
intracellular __> interstitial: depends on plasma ___
intravascular–>interstitial: depends on CAPILLARY HEMODYNAMICS AND ENDOTHELIAL function
intracellular –> interstitial: depends on plasma TONICITY
Under normal conditions with
intact endothelium, net fluid
movement dictated by ___
Law.
Endothelium is compromised
during any systemic __
state (infection, surgery, injury,
burn, etc.), which increases vascular __
and escape of __ into
tissues.
• Fluid accumulates in __
__ spaces (lung, muscle,
skin, GI)
Under normal conditions with
intact endothelium, net fluid
movement dictated by STARLINGS
Law.
Endothelium is compromised
during any systemic inflammatory
state (infection, surgery, injury,
burn, etc.), which increases vascular permeability
and escape of albumin into
tissues.
• Fluid accumulates in compliant
interstitial spaces (lung, muscle,
skin, GI)
t/f plasma tonicity is the same as osmolality
false. plasma tonicity only is a measure of effective plasma osmolality. reflects the concentration of solutes that DO NOT readily cross cell membranes, and thus effect the distribution of water between intracelular/extracellular compartments.
- water moves from compartments with HIGH tonicity to those with LOW tonicity.
- water moves from compartments with __ tonicity to those with __ tonicity.
- water moves from compartments with HIGH tonicity to those with LOW tonicity.
T/F urea contributes to plasma osmolality and plasma tonicity
false. urea contributes to plasma OSMOLALITY, but DO NOT CONTRZIBUTE to plasma tonicity.
plasma tonicity primarily reflects sodium salts
outline urine, skin, resp, and GI issues that can increase fluid input requirements
3 types of crystalloid IV fluids
- hypotonic
- isotonic
- hypertonic
2 types of colloid IV fluids
- natural– blood products, albumin
- synthetic– starches, gelatins
T/F crystalloids contain oncotically active molecules
false. they are composed of salts at various concentrations, not proteins/albumin.
discuss content, volume expansion, use, and cautions of D5W, 0.45 saline, 0.9 saline, ringers, plasmalyte, normal HCO3-, and 3% saline
NEVER use D5W or 0.45% saline to resuscitate patients with decreased __ __ volume
NEVER use D5W or 0.45% saline to resuscitate patients with decreased effective circulating volume.
too much water will go into the cells, not much will stay in the blood, will decrease volume.
Avoid unbalanced use of large volumes of 0.9% saline especially in patients with large ECV deficits
• Balanced approach using 0.9% __, __ __, __/__ solution probably better
Avoid unbalanced use of large volumes of 0.9% saline especially in patients with
large ECV deficits
• Balanced approach using 0.9% saline, Ringer’s lactate, HCO3/D5W solution probably better
Avoid ___ fluids including ___ __ (Na+) in any patient with
suspected brain injury
Avoid hypotonic fluids including Ringer’s Lactate (Na+) in any patient with
suspected brain injury
• Contain oncotically active molecules, i.e. cells, proteins, etc. within a carrier solution
COLLOIDS
• General rule is greater expansion of intravascular space compared to
same volume of crystalloid
why is there grater intravascular compartment expansion when giving colloids?
- Greater retention of volume administered within intravascular space
- Net movement of water from interstitial to intravascular space owing to increased oncotic pressure in intravascular space
natural vs synthetic colloids
t/f: Aside from use of selected blood products in patients with severe anemia, ongoing hemorrhage, and/or severe coagulopathy, there is evidence to support NOT USING COLLOIDS for resuscitation of most patients with
decreased ECV
true. this includes albumin and HES products. just give them blood.
Flow is proportional to catheter __ (to the 4th power!) and inversely proportional to catheter __
Flow is proportional to catheter Radius (to the 4th power!) and inversely
proportional to catheter Length
when should you bolus over infuse a fluid
bolus is preferred for any unstable patient or patient receiving a fluid challenge.
Note
T/F theres a survival benefit when using albumin as a volume modulatror in septic shock
false. there’s so much inflammation that the albumin is just seeping out and not helping anyway.
HES vs Crystalloid?
studies show Worse renal outcomes in hydroxy ethyl-starch. Clearly an increased risk for dialysis. The synthetic material seeped into the interstitium, causing kidney damage.
Balanced vs Unbalanced Crystalloid?
• No difference in risk of AKI, RRT, or mortality
