Fluid and Blood Flashcards
Body fluid distribution
TBW 60% ICF 40% (2/3) ECF 20% (1/3) ISF 16% (3/4) Plasma 4% (1/4)
[[need about 25-35mL/kg/day to maintain this]]
Normal electrolyte composition in body
Na+ 140 (ECF)
10 (ICF)
K+ 4.5 (ECF)
150 (ICF)
Cl- 117 (ECF)
103 (ICF/ Plasma)
Bicarb 28 (ECF)
Mg++ 2 (ECF)
40 (ICF)
Ca++ 5 (ECF)
1 (ICF)
5 (plasma)
Hypokalemia
<3.5
- caused by vomit, diarrhea, NG output, diuretics, metabolic alkalosis [[intracellular shifts]]
- skeletal muscle cramps/ weakness/ paralysis
-EKG changes PR interval --> shorter QT interval--> longer T wave--> flattened U wave present
[[treat with K+]]
Hyperkalemia
> 5.5
caused by poor excretion [[renal failure, K sparing diuretics]]
ACIDOSIS [[extracellular shifts]]
succinylcholine, tumor lysis
cardiac rhythm changes
Early;
PR –> longer
T wave –> peaked
QT –> shorter
Middle;
P–> flat
QRS–> wide
Late; VF
[[GIVE CALCIUM]] ^stabilize cardiac membrane -hypervent -insulin + D50 -bicarb
Hyponatremia
<135
can exist in all hydration states (hypo, iso, hyper)
evaluate plasma osmotic and ECF to determine cause
SIAD, CHF, Cirrhosis, TURP syndrome, Cushings
S/S N/V, SKELETAL MUSCLE WEAKNESS, mental changes [[seizure --> coma]] cerebral edema (cell swells)
[[RESTORE Na+ BALANCE]]
manipulate serum osmotic and with fluid resusitation/ diuretics
*must be done slowly
Hypernatremia
> 145
can exist in all hydration states (hypo, iso, hyper)
evaluate plasma osmotic and ECF to determine cause
DI, impaired thirst,
Sodium bicarb admin
S/S thirst, mental status changes [[coma --> seizure]] cerebral dehydration (cell shrinks)
[[RESTORE Na+ BALANCE]]
manipulate serum osmotic and with fluid resusitation/ diuretics
*must be done slowly
Hypocalcemia
<8.5
hypoPTH decreased vit D renal osteodystrophy Pancreatitis Sepsis
S/S skeletal muscle cramps nerve irritability mental status changes--> seizure CHVOSTEK SIGN [[facial spasm when tapped]] TROUSSEAU SIGN [[carpal pedal spasm when BP cuff inflated]] LARYNGOSPASM [[with PTH ectomy]]
EKG change
QT interval –> long
[[GIVE CALCIUM]]
or Vit D
Hypercalemia
> 10.5
HyperPTH cancer thyrotoxicosis thiazide diuretic immobilization *massive transfusion
S/S nausea ab pain HPTN mental status change --> seizure psychosis
EKG changes
QT intervak –> short
give 0.9% NaCl or lasix
Hypomagnesium
<1.3
alcohol abuse
common with hypoK
diuretics
critical illness
S/S
skeletal muscle weakness
TORSADES DE POINTES
[[GIVE Mg SULFATE
Hypermagnesium
> 2.5
excessive administration
[[bronchodilator or uterine relaxation]]
renal failure
adrenal insuff
Lose deep tendon reflex
4-6.5 mEq/L
10-12 mg/dL
Respiratory depression
6.5-7.5 mEq/L
>18 mg/dL
CARDIAC AREST
>10 mEq/L
>25mg/dL
[[GIVE CALCIUM CHLORIDE]]
Ca++ and Mg++ inverse relationship
Net Filtration
+ net filtration favors fluid into the tissues
- net filtration favors fluid absorption into vasculature
[[The forces that favor filtration from the capillary are capillary hydrostatic pressure and interstitial oncotic pressure, and the forces that oppose filtration are capillary oncotic pressure and interstitial hydrostatic pressure. The sum of their effects is known as net filtration pressure]]
overall balance is slightly +
filtered to interstitial space and returned to intravascular space via lymphatic system
Endothelial Glycocalyx
-gel layer capillary epithelium
creates physiologically active barrier with in vascular space
[[barrier between vessel and blood]]
binds to circulating plasma albumin
[[preserves oncotic pressure and decreases capillary permeability to water]]
contain inflammatory mediators, free radical scavenging, activation of anticoagulant factors
HYPERGLYCEMIA (hyperosmolar) major risk for damage or destruction of endothelial glycocalyx
[[alot of crystalloid can also wash it away]]
stress can damage endothelial glycocalyx
loss of endothelial glycocalyx integrity can lead to changes in transcapillary fluid dynamics in critically ill
Preop fluid assessment status
- skin turgur
- mucous membrane
- peripheral edema
- lung sounds
- VS
- HCT
- urine output
- urine spec
- BUN/Creatinine
- ABG
[[remember UO will drop in OR due to release of ADH from stress response]]
Acidosis
Cardiac; decreases contractility increases Sympathetic NS tone increased risk of arrhythmia R shift on oxyhgb curve CNS; increased cerebral blood flow and ICP
Pulm;
increased PVR
[[HYPERKALEMIA]]
Alkalosis
Cardiac;
decreased coronary blood flow
increased risk of dysthymia
Left shift on oxyhgb curve
CNS;
decreased cerebral blood flow and ICP
Pulm;
decreased PVR
[[HYPOKALEMIA]]
decreased ica
Hypotonic solution
replaces water loss
D5W [[253]]
0.45% NaCl [[154]]
Isotonic solution
aka replacement fluids
replaces water and electrolyte loss
normal osmotic
[[275-295]]
LR [[273]]
NS [[308]]
plasmalyte [[294]]
Hypertonic Solution
hyponatremia or shock
D5 1/2 NS [[405mOsm/L]]
3% NS
[[1026 mOsm/L]]
Colloids
Albumin 5% [[300mOsm/L]]
^isotonic
Dextran 10% [[350]]
^hypertonic
Hypertonic vs Hypotonic
Hyper > 300
[[cell shrinks]]
Hypo < 300
[[cell swells]]
LR
isotonic solution
^NS with K+, Ca++ and Lactate
[[273]] slightly hypotonic
^100cc free water/ L
pH 6.2 Na 130 K 4 Cl 110 Ca 3 LACTATE 28 ^mild metabolic alkalosis from lactate metabolism
K+, Ca++ and Lactate present
[[ don’t give large volume to DM pt]]
^by product of lactate is gluconeogenic
[[avoid in renal failure pt K+]]
[[don’t mix with blood Ca++]]
[[don’t give to TBI pt]]
^slightly HYPO-OSMOLAR in blood r/t LACATE
0.9% NS
isotonic [[310]] pH 5.6 Na 154 Cl 154 ^least physiologic
[[large volumes produces high Cl content –> dilution hyperchloremic acidosis–> significant impact on renal function]]
typically used two dilute PRBC –> no Ca++
D5W
hypotonic
[[260]]
not used often in period
[[neonates and DM on insulin but usually use D5 1/1 NS]]
causes FREE WATER INTOXICATION and HYPOnatremia
provides 170-200 calories/ L
[[HYPERglycemia]]
3% or 5% NaCl
hypertonic
[[1026]]
3%
[[Cl- 513 mEq/L]]
5%
[[Cl- 856 mEq/L]]
treatment for HYPOnatremia
*risk of hyperchloremia, hypernatremia, and cellular dehydration [[shrinks cell]]
[[used for renal neuro patients with SIAD]]
Osmotically active substances
high molecular weight
administered in 1:1 ratio
[[equivalent to volume of fluid/blood lost from intravascular volume]]
half -life is 16 hours
[[can also be 2-3 hrs]]
*albumin is the only natural occurring
Dextran
artificial COLLOID
[[high molecular weight]]
hyperosmolar
1/2 life 6-12 hours
side effects;
ACUTE RENAL FAILURE [[black b ox warning
anaphylaxis
[[no longer available in many countries r/t to this ]]
interference with cross matching
[[adheres to surface of platelets and RBC]]
platelet inhibition; antithrombotic effects
[[briefly used in microvascular surgery settings for this effect]]
Hetastarch
colloid derived from starchy plants
taken off US market for nephrotoxicity
Max dose; limited to <20mL/ kg/day
[[BOARD PREP]]
Albumin
colloid derived from pooled human plasma
[[heat and treated to eliminate risk of disease transmission]]
NO clotting factors or blood group antibodies
[[filtered out when heated]]
available in 5% or 25%
[[5% most used in OR]]
[[ONCOTIC PRESSUE = 20]]
Crystalloid VS Colloid
crystalloid;
-cheaper
-less likely to cause pulmonary edema
-wont cause the coagulation/antigenic problems
[[albumin won’t]]
-equally effective if given in sufficient amounts
colloid;
-prolonged increase in plasma volume by maintaining plasma oncotic pressure
- 1/2 life is 3-g hrs compared to 20-30 MIN in crystalloids
- fluid of choice in HYPOPROTEINEMIA
- less tissue edema
- less volume used
Components of traditional fluid replacement
- Baseline maintenance fluid requirement
[[use LR in most cases]] - Fasting NPO deficit
[[MIVF x hours NPO]] - Replacement of blood losses
[[1:1 for colloids vs 3:1 for crystalloids]] - Evaporation losses
[[based on invasiveness of surgery]]
4-2-1 rule
determine maintenance IVF
1st 10kg 4mL/kg [[40mL]]
^if under 10kg do 4mL x weight in Kg
2nd 10kg 2mL/kg
[[20mL]
additional Kg x 1mL
add together = MIVF rate
Fasting NPO deficit
MIVF x hours of NPO
[[if pt on MIVF there is no NPO def]]
if pt has baseline hypovolemia;
overall bigger deficit then just NPO
[[restore MAP, HR, filling pressure before induction]]
How to replace NPO deficit
1/2 replaced in 1st hour
1/4 replaced in 2nd hour
remains 1/4 replaced in 3rd hour
[[Fluid deficit 75kg male]]
115ml/hr MIVF
8 hours NPO
115 x 8 = 920cc
Replacement
460cc in 1st hour
230cc in 2nd hour
230cc in 3rd hour
Visual Estimation of Blood loss
floor and drapes
suction canister
[[talk to tech about amount of irritant]]
soaked gauze 4x4
[[10 cc of blood]]
soaked lap pad
[[100-150 cc of blood]]
Estimated Blood Volume
[[EBV]]
adult 65- 75 mL/kg
Allowable Blood Loss
[[ABL]]
estimates transfusion threshold
you will be given a starting Hct or Hgb
[[Hct = Hgb x 3]]
ABL= EBV x starting Hct - Tagret Hct / starting Hct
[[you set your target]]
*can also be done with Hgb
Evaporative loss
directly r/t surface area of surgical wound and duration of exposure
3rd space loss
r/t fluid shifts and intravascular volume def from redistribution of fluid
[[trauma, infection, SIRS, sepsis, burns, ascites]]
Guidelines for Evaporative loss
superficial trauma
[[1-2mL/kg/hr]]
minimal trauma
[[2-4mL/kg/ hr]]
moderate trauma
[[4-6mL/kg/hr]]
severe trauma
[[6-8mL/kg/hr]]
orofacial
Evaporation loss
[[1-2mL/kg/hr]]
^superficial trauma
herniorrhaphy
Evaporation loss
[[2-4mL/kg/hr]]
^minimal trauma
Major nonabdominal
or Lap abdominal surgery
Evaporation loss
[[4-6mL/kg/hr]]
^moderate trauma
Major OPEN abdominal surgery
Evaporation loss
[[6-8mL/kg/hr]]
^severe trauma
Enhanced Recovery After Surgery (ERAS)
[[new way we account for fluid loss]]
- General fluid therapy philosophy of avoidance of sodium and water overload
- Mostly questioning science behind replacement of 3rd space losses
- Conventional monitoring of HR, BP, peripheral perfusion, temperature, urine output, CVP, and biomarkers (lactate)
Goal directed fluid therapy
Uses advanced monitoring to make estimations of functional circulating volume and responsiveness to fluid
Pulse Contour Analysis
[[minimally/ non-invasive]]
Preload responsiveness by quantifying the degree of change of arterial, capnography, or pulse oximetry waveforms associated with cyclic respiratory variations
[[Stroke volume variation: >13% predicts volume responsiveness]]
Frank- Starling Mechanism
[[graph]]
- On plateau of curve, further fluid challenges will not improve hemodynamics or 02 delivery [[might actually cause more harm]]
- Overshooting curve impairs myocardial performance [[pt at risk for pulmonary edema and CHF]]
- Under the curve additional fluid increases sarcomere stretch [[more cross bridge formations]] greater CO [[preload dependence or VOLUME RESPONSIVE]]
Blood Therapy and indications for transfusion
- expand intravascular volume
- increase 02 carrying capacity
-Hbg and Hct ^clinical judgement [[assess other factors]] -CV status -CO -blood volume -anticipated blood loss -arterial oxygenation -age
PRBC
[[1 unit = 200mL]]
- increases hgb 1gm/dL
- increases hct 2-3%
Hct of 1 unit = 65-70%
[[CITRATE TOXICITY]]
^with multiple units
preserved with; citrate phosphate dextrose adenine [[CPDA]]
Type and Screen
blood test for blood type [[ABO]] and Rh factor [[positive or negative]] and antibodies
*99.94% rate of compatibility
Crossmatch
further testing with the actual unit to be administered
[[mixes pt blood with unit to test for agglutination]]
Who can get Uncrossmatched blood
men
women of non childbearing years who have never received a transfusion
Irradiated- Leukocyte reduced
irradiation
[[prevents GVHD]]
leukocyte redu ced
[[decreases rate of complication]]
^HLA alloimmunization
How long is a unit of PRBC good for
35- 42 days
Most common blood transfusion related mortality in the US
[[TRALI]]
transfusion related ACUTE LUNG INJURY
[[1:8000]]
*highest risk with FFP and platelet
Most common infectious complication of blood transfusion
Cytomegalovirus
[[1-3% of transfusion]]
Some blood storage complications
after > 14 days begin to shoe changes
- depletion. of DGP
- depletion of ATP
-HYPERKALEMIA
[[as high as 17.2]]
- altered morphology of cells
- absence of viable platelets
- hemolysis
Autologus blood
unit of PRBC
recipients own blood for possible reinfusion at a later date
can give up to 2-3 units
[[each unit needs to be donated a week apart]]
Complications with Autologus blood
- anemia
- preop MI from anemia
- administration of wrong unit
- need for more frequent blood transfusion
- febrile/ allergic reaction
Cell Saver
salvaging blood from surgical site
blood process washed and separated
[[RBC given back]]
continues circuit; but still disrupts continuity
[[jehovah witness may accept since it never leaves pt bedside]]
Contraindications of Cell Saver
- surgery with wounds contaminated with bacteria, amniotic fluid, malignant cells
- septic patients
- chemical contaiminants
Risk of Large Volume of cell saver transfusion
dilution of clotting factors and thrombocytopenia
Acute Normovolemic Hemodilution
- removes blood from patient
- replace blood volume lost with crystalloid or colloid
- after surgical blood loss has slowed or stopped patient blood transfused back to them
Platelets
multi donor unit [[6-10]]
or
single donor aphaeresis unit
5 days shelf life; stored at room temp
1 unit increases platelet count 7,000-10,000 1 hr after transfusion
Uses for Platelets
- thrombocytopenia
- dysfunctional platelets
- active bleeding
-platelet count <50,000
[[low moderate risk surgery]]
-platelet count <100,000
[[high risk surgery]]
Risk with Platelet administration
HIGH bacterial contamination
[[1:12,000]]
Fresh Frozen Plasma
contains clotting factors and plasma proteins
[[NO PLATELETS]]
stored frozen for up to 1 year
Volume 200-250cc
must be ABO compatible
Uses for FFP
urgent reversal of warfarin
known coagulation factor deficiencies
correcting microvascular bleeding in presence of increased PT and PTT
OR
correction of microvascular bleeding
in a pt transfused with more than one blood volume when PT and pTT cannot be obtained in a timely fashion
FFP is NOT for..
augmentation of plasma volume or albumin concentration
Cryoprecipitate
derived from precipitate remaining after FFP thawed
contains;
- Factor VIII
- XIII
- fibrinogen
- von Willebrand factor
- plasma
- fibronecnin
ABO compatible
given through a filter rapidly [[200mL/hr]] and completed within. 6 hours
Whats is cryo used for
to treat;
-von Willebrand’s disease
-fibrinogen deficiencies