IV fluids and Blood Products

Question 1

Fxn of blood? What can impair this?

Answer 1

• deliver O2 to tissues
• anemia can impair O2 delivery
• Oxygen delivery is determined by the formula:
  DO2 = COxarterial O2 content
• can tolerate Hgb down to 10 b/f O2 demand starts exceeding supply

Question 2

Transfusion risks?

Answer 2

• infection
• allergic and immune transfusion rxn
• volume overload: elderly, kids, CHF
• Hyperkalemia: newborns, renal failure, massive transfusions
• Iron overload: large number of transfusions: ex
  chronic anemia in those who have repeat transfusions

Question 3

What is considered a a massive transfusion? Complications (PATCH)?

Answer 3

• replacement of blood volume in 24 hr period of more than 50% of blood vol in 4 hrs
• complications: PATCH
  Platelets decrease, K+ increases
  ARDS, acidosis
  Temp decrease
  Citrate intoxication
  Hemolytic rxn
• don’t forget about coag factors if replacing blood w/ PRBCs - may need until of FFP

Question 4

What is a type and screen?

Answer 4

• determines ABO and Rh status and presence of most commonly encountered ABs
• risk of adverse rxn - 1:1000
• takes about 5 min

Question 5

What is a type and crossmatch?

Answer 5

• determines ABO and Rh status as well as adverse rxn to even low incidence Ags
• risk of adverse rxn - 1:10,000
• takes about 45 min

Question 6

What are the transfusion thresholds?

Answer 6

• no universal guidelines
• decision to transfusion shouldn’t be based on Hgb/Hct levels alone
• no role for transfusion at Hgb of more than 10 g/dL
• depending on clinical situation and the society’s guidelines: range of transfusion is anywhere from Hgb 6-10 g/dL
• studies indicate that target Hgb values of 7-8 g/dL are assoc w/ equivalent or better outcomes in many pt pop: compared w/ Hgb of 10 g/dL

Question 7

Why not transfuse bf Hgb gets so low?

Answer 7

• rate of normal O2 delivery exceeds consumption by factor of 4
• theoretically if fluid vol and CV status is maintained O2 delivery will be adequate until Hct goes below 10
• compensatory mech: increased CO, rightward shift of O2-hemoglobin dissociation curve, increased O2 extraction

Question 8

What should be the components of your deciding to transfuse?

Answer 8

• Hgb level
• clinical status
• co-morbidities
• pt preference
• can check Hgb/Hct 15 min post infusion to assess status (if not actively bleeding)
• if stable - considere transfusing one unit of PRBCs at a time (instead of mult units in initial order)

Question 9

What is in cryoprecip? When should it be given?

Answer 9

• fibrinogen, vWF, VIII, fibronectin

- if pt needs fibrinogen like in DIC give Cryo

Question 10

When should you use FFP?

Answer 10

- need clotting factors:
reverse warfarin
transfusing PRBCs 
large transfusions 
liver disease: pre surgery

Question 11

When do you transfuse platelets?

Answer 11

• sx thrombocytopenia

Question 12

Rarest blood type?

MC blood type?

Answer 12

• rarest: AB -

- MC: O+, A+

Question 13

What are crystalloids?

Answer 13

• solns that contain small molecules and are able to pass through semipermeable membranes
• isotonic: expand ECF
• hypotonic: given to reverse dehydration
• hypertonic: given to increase ECF and decrease cellular swelling

Question 14

What are colloids?

Answer 14

• solns that contain high MW proteins or starch
• don’t cross capillary semipermeable membrane and remain in intravascular space: pull fluid out of intracellular and interstitial space for several days

Question 15

ex of Colloids?

Answer 15

• albumin
• dextran
• hexastarch

Question 16

ex of crystalloids?

Answer 16

• D5W, D10W, D50W
• saline
• combo: D5 1/2 NS, D5NS, D10NS
• ringer’s lactate

Question 17

Intracellular vs extracellular?

Answer 17

- intracellular:
inside body cells
2/3 total body water
- extracellular:
intravascular space
interstitial space 
1/3 of total body water

Question 18

S/S of intravascular depletion?

Answer 18

• decreased BP, flat jugular veins
• increased HR
• cool extremities

Question 19

S/S of interstitial fluid depletion?

Answer 19

• decreased skin turgor, sunken eyeballs, wt

- can also have hemodynamic effects

Question 20

If given 1 L of dextrose how is it handled?

Answer 20

• ECF 1/3: 300 ml
  1/4 of ECF: 75 ml
• ICF 2/3: 700 ml
• handled like free water, will diffuse just like body water, don’t give to pt bleeding (intravasc deficit)

Question 21

If given 1 L of 0.9% NS how is it handled?

Answer 21

• isotonic - distributed in ECF since cell membrane not permeable to Na
• so ECF gets the full 1 L
  interstitial: 3/4 (750 ml)
  intravasc: 1/4 (250 ml)

Question 22

How is 1 L of 5% albumin and PRBCs handled?

Answer 22

• remains in intravascular space

- intravascular space = 1 L `

Question 23

How is 1/2 NS handled?

Answer 23

• 1/2 as free water (goes out into ICF)

- 1/2 as saline (stays in ECF)

Question 24

Which lytes are lost in sweat and exhaled water vapor?

Which ones are lost in urine?

Answer 24

• none are lost in sweat and water vapor
• all lytes are lost in urine:
  renal failure pts don’t need maintenance Na or K

Question 25

How is Na regulated?

Answer 25

• serum Na = osmolality = water
• Na is regulated by thirst, ADH, renal water handling
• a disruption in water balance is manifested as an abnorm in serum Na
• Na is fxnlly impermeable solute so it contributes to tonicity and induces water movement across membranes

Question 26

What will Na levels be in loss from a GI source?

Answer 26

• high because lost everything else

- replacing w/ fluid fixes problem

Question 27

Fluid loss occurs via?

Answer 27

• GI
• Renal
• vascular
• skin

Question 28

Fluid gain occurs via?

Answer 28

• iatogenic (fluid replacement)
• heart failure
• liver failure (albumin decreases - oncotic pressure decreases - fluid leaks out from vasculature)
• kidney failure

Question 29

25 yo pt presents w/ massive hematemesis x 1 hr and has hx of PUD, diaphoretic w/ normal skin turgor. Orthostatic hypotension, Na of 140, What fluids should be given?

Answer 29

• bleeding so want intravasc replacement -

can do NS

Question 30

18 yo w/ severe D/V x 48  hrs 
- exam: sunken eyeballs, poor skin turgor, dry mucous membranes
- BP 80/60, HR 130 supine
labs:
Na 148, K 2.8, HCO3 22
WHat should be done?

Answer 30

• extracellular depeletion = interstitial
• has hypernatremia, and hypokalemia
• needs crystalloid - LR or NS w/ K+
• most likely has metabolic alkalosis from vomiting

Question 31

85 yo F nursing home resident w/ known dementia presents w/ worsening confusion -
exam: disoriented, decreased skin turgor, has slight Ortho hypotension, labs - Na 150, Hct 45, BUN/Cr 50/1.8, blood glucose 1200 -
what does pt have? Correction?

Answer 31

• DKA: has high K as well (hyperkalemia in DKA)
• tx w/ insulin drip (will drive K+ back into cell)
• need massive fluid replacement w/ DKA - NS or 1/2 NS (b/c high Na)
• check K+ levels hourly

Question 32

What are the rules of fluid replacement?

Answer 32

• replace blood w/ blood
• replace plasma w/ colloid
• resuscitate w/ colloid or Ringers
• rehydrate w/ dextrose if you want fluid distributed to all body compartments