Fluid Therapeutics

How is vascular access gained?

• peripheral intravenous (IV) line

  • 16 gauge through 22 gauge needle

• Central IV line

• “mid line”

• PICC

IV Fluid Options

D5W, 0.45% NaCl, 0.9% NaCl, 3% NaCl, Lactated Ringers, 5% albumin

D5W tonicity

hypotonic

0.45% NaCl tonicity

hypotonic

0.9% NaCl tonicity

isotonic

3% NaCl tonicity

hypertonic

lactated ringers tonicity

isotonic

5% albumin tonicity

isotonic

pH of lactated ringers

6.5

pH of plasma-lyte A

7.4

lactated ringers composition

• Sodium 130mEq/L

• Chloride 105mEq/L

• Lactate 28mEq/L

• Potassium 4mEq/L

• Calcium 3mEq/L

plasma-lyte A composition

• Sodium 140mEq/L

• Chloride 98mEq/L

• Potassium 5mEq/L

• Magnesium 1.5mEq/L

• Acetate 27mEq/L

• Gluconate 23 mEq/L

balanced crystalloids

mimic plasma electrolyte concentrations; closer to neutral pH (normal saline pH=5.5)

Maintenance Fluid Calculation

Pediatrics 4-2-1 riule

Children >20 kg: 1500 mL + 20 mL/kg per kg >20 kg up to a maximum of 2400 mL

Adults: follow > 20 kg rule of 30-35 mL/kg

typical rate for adults ~100-125 mL/hr

Common OTC Fluids

Gatorade, Powerade, Pedialyte, Liquid IV

Tonicity of common OTC fluids

hypotonic

what happens if you give IV isotonic fluid

it will stay in the extracellular fluid space

what happens if you give IV hypotonic fluid

it will shift water into the intracellular space

what happens if you give IV hypertonic fluid

it will pull water out of the intracellular space

what is intravascular volume directly linked to?

hemodynamics (BP and HR)

what does hemodynamic instability (low BP, high HR) need?

bolus isotonic crystalloids or bolus iso-oncotic colloids until improvement in hemodynamics

what is dextrose 5% in water (D5W)?

FREE WATER

what happens if you give free water?

free water will shift into the intracellular space to maintain tonicity; cells swell and can BURST

what happens if you give hypertonic fluids? (ex. 1000 mL of 3% NaCl)

rapid ECF expansion → 750 mL interstitium; 250 mL intravascular Sodium increases since hypertonic; water shifts from ICF → ECF to balance tonicity; cells _shrink ;ECF expands = edema

Hypotonic Loss

free water will shift from ICF → ECF to maintain tonicity

1000 mL of Dextrose 5% in water will increase intravascular volume by:

100 mL

1000 mL of Normal Saline in water will increase intravascular volume by:

250 mL

1000 mL of Lactated Ringers/PlasmaLyte in water will increase intravascular volume by:

250 mL

1000 mL of ½ normal saline in water will increase intravascular volume by:

175 mL

1000 mL of 5% albumin in water will increase intravascular volume by:

1000 mL

1000 mL of 3% saline in water will increase intravascular volume by:

832 mL (but pulled 2331 mL from ICF)

Complications of fluids

• volume overload (especially with sodium containing solutions)

• saline solutions: hyperchloremic metabolic acidosis

• lactated ringers: alkalosis

• electrolyte abnormalities

  • hyponatremia with D5W

  • hypernatremia with NS

When to give less than the maintenance fluid amount

CKD, Chronic Liver Disease, Mild heart failure; severe heart failure, end-stage renal disease

what adjustment do you make to fluid amount if patient has CKD, Chronic Liver Disease, Mild heart failure

0.75x

what adjustment do you make to fluid amount if patient has severe heart failure, end-stage renal disease

0.5x

when to give the maintenance fluid amount

• patient is NPO for procedure

• CKD with mild dehydration

• ESRD with severe dehydration

• HF with moderate dehydration

when to give more then the maintenance fluid amount

mild dehydration, moderate dehydration, severe dehydration, hemodynamic shock

what adjustment do you make to fluid amount if patient has mild dehydration

1.25x

what adjustment do you make to fluid amount if patient has moderate dehydration

1.5x

what adjustment do you make to fluid amount if patient has severe dehydration

2x

what adjustment do you make to fluid amount if patient is in hemodynamic shock

large volume boluses

True or False: Isotonic crystalloids (normal saline, lactated ringers, etc.) are the go-to, gold standard for fluid resuscitation

True!

True or False: 5% albumin offers survival advantage compared to NS in resuscitation

False!

what patient population should D5W be avoided in?

diabetics due to risk of hyperglycemia

Clinical Pearls: too much fluids

volume overload, increased pre-load, edema

Clinical Pearls: too little fluids

lack of correction of dehydration, worsening of underlying process (ex. AKI)

what is fluid compatibility?

when more than 1 fluid is administered intravenously, you need to check for chemical or physical interaction

precipitation interaction

particulate emboli

inactivation of compound

therapeutic failure

tissue irritation

due to pH changes or damage from toxic solutions

interaction between ceftriaxone + calcium

precipitation

interaction between sodium bicarbonate + calcium

precipitation

interaction between sodium bicarbonate + epinephrine

inactivation of epinephrine

interaction between diazepam + sodium chloride

precipitation (IV diazepam incompatible with MOST of fluids and drug)

D5W Composition

Dextrose: 5g/dL

Na: 0

Cl: 0

%ECF: 40

%ICF: 60

Free Water: 1000 mL

0.45% NaCl Composition

Dextrose: 0

Na: 77

Cl: 77

%ECF: 73

%ICF: 37

Free Water: 500 mL

0.9% NaCl Composition

Dextrose: 0

Na: 154

Cl: 154

%ECF: 100

%ICF: 0

Free Water: 0 mL

3% NaCl Composition

Dextrose: 0

Na: 513

Cl: 513

%ECF: 100

%ICF: 0

Free Water: -2331 mL

Lactated Ringers Composition

Dextrose: 0

Na: 130

Cl: 105

%ECF: 97

%ICF: 3

Free Water: 0 mL

5% Albumin Composition

Dextrose: 0

Na: 0

Cl: 0

%ECF: 100

%ICF: 0

Free Water: 0 mL

Gatorade Composition

Na: 20

K: 3

Cl: 20

Bicarbonate: 0

Total Electrolytes: 43

Dextrose: 330

Osmolality: 280-360

Non-dextrose Osmolality: 43

Powerade Composition

Na: 10

K: 3

Cl: 10

Bicarbonate: 0

Total Electrolytes: 23

Dextrose: 350

Osmolality: 403

Non-dextrose Osmolality: 23

Pedialyte Composition

Na: 45

K: 20

Cl: 35

Bicarbonate: 0

Total Electrolytes: 100

Dextrose: 139

Osmolality: 255

Non-dextrose Osmolality: 100

Liquid IV Composition

Na: 46

K: 20

Cl: ?

Bicarbonate: ?

Total Electrolytes: ?

Dextrose: Depends

Osmolality: ?

Non-dextrose Osmolality: ~70

NS D5W Composition

Dextrose: 5

Na: 154

Cl: 154

K: 0

Tonicity: isotonic

%ECF: 100

%ICF: 0

Free Water: 0 mL

NS D5W with 20 mEq KCl Composition

Dextrose: 5

Na: 154

Cl: 154 +20 = 174

K: 20

Tonicity: hypertonic

%ECF: 100

%ICF: 0

Free Water: about -125 mL

½ NS D5W Composition

Dextrose: 5

Na: 77

Cl: 77

K: 0

Tonicity: hypotonic

%ECF: 73

%ICF: 37

Free Water: 500 mL

½ NS D5W with 20 mEq KCl Composition

Dextrose: 5

Na: 77

Cl: 77+20=97

K: 20

Tonicity: hypotonic

%ECF: 78

%ICF: 22

Free Water: ~370 mL

½ NS D5W with 40 mEq KCl Composition

Dextrose: 5

Na: 77

Cl: 77+40= 117

K: 40

Tonicity: hypotonic

%ECF: 86

%ICF: 14

Free Water: ~240 mL