Vascular Access Flashcards
how is fluid (water) volume distributed?
extracelluar (insterstitial & plasma) 35%
Intracellular 65 %
Blood volume (RBC & Plasm) 14%
what is true of osmolality?
its the count of the total number of particles in a solution
it is equal to the sum of the molalities of all the solutes present in that solution (osmol/kg)
Hyperosmotic
Hypoosmotic
the concentration of an osmotic solution per 1000 grams of solvent
what is the concentration of osmotic solution per liter of fluid
osmolarity
what produces osmotic pressure across cell membranes?
ions
what is oncotic pressure?
Large protein molecules produce colloid osmotic pressures (oncotic pressures) across capillary membranes
what is normal osmotic pressure?
285 mOsm/L
what is normal oncotic pressure?
28 mmHg
what term is Frequently used in place of osmotic pressure or tension, is related to the number of non-penetrating particles found in solution
tonicity
(used in association to RBCs)
what is the term for equal tension. Denoting a solution having the same tonicity as another solution with which it is compared
isotonic
define hypertonic
Having a higher concentration of solute particles per unit volume than a comparison solution, regardless of kinds of particles
what happens to cells in hypertonic solution
cells shrink due to efflux of water
What is term for - Having a lower concentration of solute particles per unit volume than a comparison solution, regardless of kinds of particles.
hypotonic
what happens to cells in a hypotonic solution
cells expand due to influx of water.
What are normal values for Plasma Ca
8.5 -10 mEq/L
what are normal values for plasma Mg
1.5 - 2.5 mEq/L
what are normal plasma levels for PO4 and SO4
PO4 - 0.5 –1.5 mEq/L
SO4 - 0.3 - 0.6 mEq/L
what’s in D5W?
dextrose (5 g/l)
Water
what’s in 0.9 NaCl
Na - 154 meq/l
Cl -154 meq/l
what’s in LR?
Na - 130 meq/L
Cl - 109 meq/L
K - 4 meq/L
Ca - 3 meq/L
Lactate - 28 meq/l
what’s in plasma - Lyte?
Na - 140 meq/L
Cl - 98 meq/L
K - 5 meq/L
Mg - 3 meq/L
acetate
gluconate
what’s in hetastarch?
Na - 154 meq/L
Cl - 154 meq/L
hyrdoxyethyl starch
what’s in Dextran 70?
Na - 154 meq/L
Cl - 154 meq/L
Which IV fluids are hypotonic
D5W
LR (slightly)
which fluids are hypertonic?
slightly:
NS
plasma-lyte
hetastarch
dextran 70
5% albumin
extremely:
3% & 5% Na
which patients would you avoid giving LR?
patient’s getting blood (d/t Ca)
Renal failure
DM (kidney issues)
which crystalloid is ok to use for renal failure patients?
NS
what dictates whether the solution should be delivered via the peripheral or central venous route
tonicity of an IV fluid
what is true of . Extremely hypotonic and hypertonic solutions
may be infused in small volumes and into large vessels, where dilution and distribution are rapid
what are some issues that IV solutions may cause?
Tissue irritation
Pain on injection, and
Electrolyte shifts.
Inflammatory and
Enhanced clotting processes
Phlebitis and thrombophlebitis.
what is generally accepted upper limit for a peripheral IV fluid osmolarity?
900 mOsm/L
what is fluid replacement therapy for healthy adult?
100-200 ml/day GI
500-1000 ml/day insensible loss
1000 ml/day urinary loss
Total ~2500 ml/day
what is the 4-2-1 fluid maint. rule?
Example: 70kg pt
4ml/kg/hr*10kg = 40 ml/hr
2ml/kg/hr*10kg = 20 ml/hr
1ml/kg/hr*50kg = 50 ml/hr
70kg = 110 ml/hr
what is sensible fluid loss for surgeries?
2-4 ml/kg/hr minor surgery (hernia)
4-6 ml/kg/hr moderate surgery (chole)
6-10 ml/kg/hr major surgery (bowel resection)
what should urine output be?
MINIMUM 0.5ml/kg/hr
Fluid calculation in simulated case for hystorectomy on 70kg female.
NPO Deficit 10 hrs = 1100 ml NS
Maintenance 110 ml/hr
Blood loss = 300 = 900 ml NS
Sensible loss 4 ml/kg/hr = 280 ml/hr
Total case 3 hours = 1100+330+900+840 = 3170 ml
what are examples of preoperative fluid losses
Bowel prep
Vomiting/diarrhea
Burns
Malnourished
Ascites
Pulmonary Effusion
what are examples of operative fluid loss?
blood loss
Suction canisters
Surgical sponge (4x4)
10mL blood
“Lap pads”
100-150mL blood
What can blood products improve that crystalloids can’t?
O2 carrying capacity (i.e. Hb)
what is true of crystalloid fluids?
Crystalloids in sufficient amounts as effective as colloids in restoring intravascular volume.
Crystalloids require 3x volume of colloids/blood when replacing lost volume.
Rapid admin crystal >4L associated with tissue edema.
what are advantages of colloids?
smaller infused volume
prolong increased plasma volume
less peripheral edema
greater O2 delivery
decreased thromboebolism risk (dextran)
what are some disadvantages of colloids?
expensive
coagulopathy (decreaesed ability to clot)
decreased GFR
pulmonary edema
what are the advantages of cyrstalloids?
less expensive
greater GFR
replace IFV losses
What are some disadvantages of crystalloid?
short lived hemodynamic improvement
peripheral edema
pulmonary edema (conflicting data)
Which crystalloid solution can cause hypochloremic metabolic acidosis?
NS
which crystalloids would you use on patients that have Na restriction (i.e. CHF patients)
D5W
D5NS
how long do colloid stay in the intravascular compartment?
albumin 3-4 hrs
Dextran 6 -12 hrs
hetastarch 6 -12 hrs (17 d)
what colloid has a 1/2 life of 25.5 hours?
hetastarch
what is cell saver composed of ?
on RBC, no clotting factors
How much is HCT increased with each unit of PRBC?
3%
how much is Hgb increase with each unit of PRBC?
1 g/dL
What is true of Hgb and transfusion of PRBC recommendations?
rarely indicated for Hgb > 10 g/dL
almost always for Hgb < 6 g/dL
What is true of PRBCs?
Admin pt. who require RBC but no volume
Carefully checked against blood slip and patient ID by 2 people
Transfusion w/170 micron filter
Blood warmed prior to infusion
why is blood warmed prior to administration?
hypothermia can cause coagulation problems
which is more sensitive a type & cross or a type & screen?
type and cross
(confirm ABO and Rh type)
actually mix blood together to confirm no reactions
What are the transfusion recommendations for Platelets?
Plt < 50k increase Sx blood loss
Oncology Pt >10,000/mm3
Target > 100k/mm3
Each unit will increase count by 5-10k/mm3
Platelet phoresis pooled 6-8 donor (200-400 ml)
Admin. through 170 micron filter
what is should not be done to platelets prior to administering?
do NOT warm them
What are the transfusion recommendations for FFP
Contains all plasma proteins & factors II, V, VII, IX, X, XI, and AT III
Unit clotting factors 2-3%
Should be warmed 37
what is true of platelets and FFP
they do not have antigens do they do NOT have to be ABO typed
what factors does cyropercipitate have?
VIII,
fibrinogen,
von Willebrand factor,
XIII
what are indications for arterial lines?
BP monitoring
Blood sampling
Deliberate Hypotension
what sites for arterial lines
Radial
Brachial
Femoral
Dorsalis Pedis
what test should be done for collateral cirulation prior to inserting art. line?
Allen’s test (5 to 10 second refill)
Doppler
Pulse Oximeter
which patient population has contraindications for radial and ulnar art. lines?
raynaud’s
what are some risk associated with artery catherization?
Vascular thrombosis
Distal embolization
Proximal embolization
Vascular spasm
why do we put in central Lines?
Monitoring central venous pressure
Fluid administration
Infusion of caustic Rx
TPN (total parenteral nutrition)
Air emboli aspiration
Transcutaneous pacing leads
Poor peripheral access
what are contraindications to central venous catheterization?
R atrial tumors
Fungating tricuspid valve vegetations
Suspected injury to IVC or SVC
what are central venous routes?
Peripheral Arm Veins (PICC)
Femoral vein
External jugular
Internal jugular*
Subclavian vein
what technique is used for central venous catherization?
seldinger’s
what are some complications associated with central venous lines?
Infection
Pneumothorax/hemothorax
Air embolism
Arrhythmias
Carotid artery puncture/cannulation
What type of access for a 50 year old 70kg for 30 minute lap chole
peripheral
what type of access for a 24 year old for 18 hour spinal fusion
art line
central line
peripheral
what type of access for a 75 year old with CAD, HTN, CHF for total hip replacement
art line
central line
peripheral line
What type of assess for a 46 year old with ESRD, MWF dialysis for AV fistula revision
peripheral (if you can get it)
when evaluating ABGs, what could cause the Hct to increase? (no blood products have been given)
dehydration
In regards to ABG evaluation, what would expect to see with an accute loss of blood?
decrease Hct
increase in lactate (anaerobic metabolism – metabolic acidosis b/c not enough oxygen being delivered to tissue due to blood loss)
After administering PRBC, what would you expect to see in the ABG of a patient being treated for acute blood loss?
increase Hct
increase K (free K in PRBC)
decrease in Lactate (d/t citrate in blood)
why does blood glucose increase with acute blood loss?
endogenous catecholamine release
