Fluids/Blood Flashcards
what’s Na content of 5% OR 25% albumin?
154 mEq/L
what’s an alternative to normally-mixed Albumin?
mixed with D5W instead of NS
What is total body fluid for men?
Women?
(Liters & percent)
men - 60% lean body weight
(.6*kg) = L; ~45 L
Women - 50% lean body weight
(.5*kg) = L; ~ 30 L
Volume of blood in males/females?
M - 66mL/Kg ~ 5L
F - 60mL/Kg ~ 3.6L
What percent of blood is plasma vs red cells?
40% - RBC
60% - plasma
How much of TOTAL body fluid is extra cellular?
40%
What two compartments make up extra cellular fluid? (Extracell fluid=40%)
ExtraVascular (interstitial)
IntraVascular (plasma)
Plasma relates to interstitial fluid volume how?
Plasma vol is 25% of the amount of interstitial vol
3L vs 12L
WHAT aspect of fluid we give creates an equilibrium problem?
- in what space?
SODIUM equilibrates throughout EXTRACELLULAR fluid (extracellular is 40% of total body fluid):
- extracellular = 25% plasma (intravasc) plus 75% (interstitial)
3: 1……. interstitial fluid:intravasc fluid
Two COMPENSATORY responses to acute blood loss?
1) interstitial fluid drain to capillaries/blood (+1L max to plasma)
2) RAS response - increase sodium conservation by kidneys
RAS response primarily enhances volume for where?
Interstitial volume
How many classes of blood loss are there?
4
Class 1 blood loss….how much?
How compensate?
Class2 blood loss amount?
How compensate?
findings?
15-30% blood loss
- systemic vasoconstrictor response
- SEE = postural changes in pulse rate and BP
Where is vasoconstrictor response MOST intense in class 2 blood loss? -consequences of that?
- splanchnic circulation
- –splanchnic hypoperfusion can lead to disruption of intestinal mucosa
Class III blood loss volume?
-otherwise known as?
30-45%
-aka hemorrhagic SHOCK
Clinical consequences of class III blood loss
Supine hypotension, impaired organ perfusion, anaerobic metabolism
Evidence of impaired organ perfusion by?
Cool extremities, oliguria, depressed consciousness
Class IV blood loss amount?
Greater than 45% of blood volume
Clinical manifestations of class IV blood loss?
- multi organ failure
- severe metabolic acidosis
What is MOST SENSITIVE and SPECIFIC physical sign of severe blood loss (630-1150mL)?
97%/98%
POSTURAL PULSE increment
(⬆ >️30 HR)
Two ways of measuring cardiac filling pressures? (Old school)
- CVP
- pulm artery occlusion pressure
why should CVP NOT be used to make decisions regarding fluid management?
Consistent lack of correlation btwn CVP and blood volume
what is pattern of O2 use/ transport with hemorrhage or hypovolemia?
- DECREASE in systemic O2 delivery
- INCREASE in O2 extraction
Hypovolemic shock, what is VO2’s result?
(VO2 = consumption of O2)
Abnormally low!!
–> hard to measure these parameters in acute hemorrhage
When do you first see DYSOXIA?
With hemorrhagic shock (30% blood vol loss)
- enhanced glycolysis
- elevated lactate
Active hemorrhage monitored via what 2 means?
1) serum lactate
2) arterial base deficit
Which marker of tissue oxygenation was found to be SUPERIOR in predicting outcomes followed after ICU admission?
- LACTATE > Base deficit
- both equally predictive on admission, however
Normal arterial base deficit?
classify mild arterial base deficit
2-5 mmol/L
Moderate arterial base deficit
6-14 mmol/L
Severe base deficit
> 15
Threshold for life-threatening lactate vs elevated lactate?
- elevated >2
- life-threatening >4
End point of resuscitation for hemorrhagic shock?
Normalization of lactate levels within 24 hrs
Recommended method for evaluating fluid responsiveness?
Fluid challenge (bolus)
Fluid challenge favored in clinical studies?
500mL of isotonic saline infused over 10-15min
Alternative fluid challenge? How work?
Passive leg raise.
- 150-750mL dumped into circulation
- 10-15% increase in aortic blood flow rate predicts fluid responsiveness - 90% sens, 90%specif
What is limitation of leg-raising as alternative fluid challenge?
Increased intra-abdominal pressure
Name of equation that relates FLOW of catheter to its radius and length?
Hagen-Poiseuille
How is radius of catheter related to flow?
Flow is directly related to 4th power of inner radius
How is length of catheter related to its flow?
Inversely proportional; longer catheter, less flow
Viscosity of fluid related to flow thru catheter?
Viscosity of fluid Indirectly related to its flow
Packed RED BLOOD CELLS has Hct of?
55%-60%
First priority in bleeding patient?
Support cardiac output
Estimating resusc volume?
1) est wnl blood vol (66ml/kg)
2) est % blood vol LOST
3) lost vol * Bl vol = deficit
4) deficit * 0.6 = Plasm vol def
5) 1/4 colloids; 3/4 crystalloids
Penetrating trauma resuscitation?
Permitting low BP until BLEEDING CONTROLLED
What is ratio of blood product resuscitation?
-monitoring goals
6units PRBCs: 1unit FFP
BUT…..
trauma: 1-2units PRBC: 1FFP
–keep INR 50K
