IV fluids and Blood Products Flashcards
Fxn of blood? What can impair this?
- 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
Transfusion risks?
- 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
What is considered a a massive transfusion? Complications (PATCH)?
- 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
What is a type and screen?
- determines ABO and Rh status and presence of most commonly encountered ABs
- risk of adverse rxn - 1:1000
- takes about 5 min
What is a type and crossmatch?
- 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
What are the transfusion thresholds?
- 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
Why not transfuse bf Hgb gets so low?
- 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
What should be the components of your deciding to transfuse?
- 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)
What is in cryoprecip? When should it be given?
- fibrinogen, vWF, VIII, fibronectin
- if pt needs fibrinogen like in DIC give Cryo
When should you use FFP?
- need clotting factors: reverse warfarin transfusing PRBCs large transfusions liver disease: pre surgery
When do you transfuse platelets?
- sx thrombocytopenia
Rarest blood type?
MC blood type?
- rarest: AB -
- MC: O+, A+
What are crystalloids?
- 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
What are colloids?
- 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
ex of Colloids?
- albumin
- dextran
- hexastarch
ex of crystalloids?
- D5W, D10W, D50W
- saline
- combo: D5 1/2 NS, D5NS, D10NS
- ringer’s lactate
Intracellular vs extracellular?
- intracellular: inside body cells 2/3 total body water - extracellular: intravascular space interstitial space 1/3 of total body water
S/S of intravascular depletion?
- decreased BP, flat jugular veins
- increased HR
- cool extremities
S/S of interstitial fluid depletion?
- decreased skin turgor, sunken eyeballs, wt
- can also have hemodynamic effects
If given 1 L of dextrose how is it handled?
- 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)
If given 1 L of 0.9% NS how is it handled?
- 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)
How is 1 L of 5% albumin and PRBCs handled?
- remains in intravascular space
- intravascular space = 1 L `
How is 1/2 NS handled?
- 1/2 as free water (goes out into ICF)
- 1/2 as saline (stays in ECF)
Which lytes are lost in sweat and exhaled water vapor?
Which ones are lost in urine?
- none are lost in sweat and water vapor
- all lytes are lost in urine:
renal failure pts don’t need maintenance Na or K
How is Na regulated?
- 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
What will Na levels be in loss from a GI source?
- high because lost everything else
- replacing w/ fluid fixes problem
Fluid loss occurs via?
- GI
- Renal
- vascular
- skin
Fluid gain occurs via?
- iatogenic (fluid replacement)
- heart failure
- liver failure (albumin decreases - oncotic pressure decreases - fluid leaks out from vasculature)
- kidney failure
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?
- bleeding so want intravasc replacement -
can do NS
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?
- extracellular depeletion = interstitial
- has hypernatremia, and hypokalemia
- needs crystalloid - LR or NS w/ K+
- most likely has metabolic alkalosis from vomiting
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?
- 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
What are the rules of fluid replacement?
- 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