Fluid Therapy

Functions of Water in the Body

• Building of cell protoplasm

• Protection and lubrication of body tissues

• Component of osmoregulation and homeostasis

• Transport medium (blood, immune cells, nutrients, hormones, chemical messengers, waste, etc.)

• Regulation of body temperature

Principal of Macroscopic Electroneutrality

• Positive and negative charges w/in a sompartment balance out so that there is no net chcarge

• Membranes btwn. compartments are selectively permeable, allowing movement of small ion but restrict large particles

  • Results in a concentration gradient of an ion across a membrane while maintaining electroneutrality

Diffusion

Process resulting from random motion of molecules by which there is a net flow of particles from a region of high [] to a region of low []

Hypertonic Solution

• H2O travels from intracellular fluid into interstitial fluid (net osmosis from intra to inter)

• Cell shrinks and wrinkles

Isotonic Solution

• No net osmosis between interstitial fluid and intracellular

• Functioning cell of normal size

Hypotonic Solution

• Net osmosis goes from interstitial fluid to intracellular fluid; H2O goes from interstitial fluid to intracellular fluid

• Cell swells up and bursts

Osmosis

Spontaneous passage or diffusion of water through a semipermeable membrane

Osmotic Pressure

The pressure that must be applied ti stop the flow of water across a semi-permeable membrane

Hydrostatic Pressure (Type of Osmotic Pressure)

The pressure exerted by a solution at equilibrium

Oncotic Pressure

Proteins unable to cross compartment membranes draw water from external compartments

Total Body Fluid Breakdown (%s)

Total Body Fluic (TBF)

• 50-60% body mass in adults

• 60-80% body mass in neonates/peds

Intracellular Fluid (ICF)

• 2/3 TBF

Extracellular Fluid (ECF)

• 1/3 TBF

• 80% Interstitial Fluid

• 20% ECF

Fluid Composition

Intracellular

• Anion

  • Proteins

  • ATP

• Cation

  • Potassium

  • Magnesium

Extracellular

• Anion

  • Chloride

  • Bicarbonate

  • Proteins

• Cation

  • Sodium

Fluid Administration

• Increase blood volume

  • therefore ^^ blood flow

  • therefore ^^ blood pressure

• Increasing perfusion to organs and tissues by increasing blood volume

  • Shock

  • Burns

  • Severe dehydration

• Things to consider:

  • IV site and gauge

  • Fluid type, flow rate, volume to be delivered

  • Total body fluid volume and intravascular volume

  • O2 and clotting impariment

Sodium (Crystalloid Fluid)

• 0.9%, 0.45%, 3%, 7.5% NaCl

• Causes hyperchloremic acidosis

• High sodium load

• Drug and fluid compatibility

• pH: 5.5

• Osm: 308

• Na: 154

• Cl: 154

Ringer’s (Crystalloid Fluid)

• Closer to plasma pH, contains a lactate buffer

• Contains Ca

  • Continuous infusion INCOMPATIBLE with some drugs

• pH 6.5

• Na 130

• Osm 273

• Cl 109

• K 4

• Ca 3

• Lactate 28

Dextrose (Crystalloid Fluid)

• D5W, D10W, D5NS, D5+0.45NS

• Physiologically hypotonic due to rapid uptake of dextrose

• Not a resus fluid

• INCOMPATIBLE with several drugs

• pH 3.5-6.5

• Osm 252

• No electrolytes

Crystalloid Infusion Overview

• Supply water and electrolyes

• Help maintain osmotic gradient btwn extra-and intra-vascular compartments

• Plasma-volume expanders due to [Na+]

• No proteins (colloids)

Crystalloid Infusion Indications

• Better for replacing losses rather than expanding plasma volume

• Used as maintenance fluids

• Compensate for insensible fluid losses

• Manage specific fluid and electrolye disturbances

• Promote urinary flow

• To keep IV catheters patent when not in use

Crystalloid Infusion Contraindications

• evidence of fluid overload

• severe left ventricular dysfunction

Crystalloid Infusion Precautions

• Pts w heart failure, renal failure, severe electrolyte disturbances

• ONLY give as LAST RESORT in HEMORRHAGIC SHOCK

• In cases where large fluid amounts may have been administered, it might be prudent to use lactated Ringer’s solution

Crystalloid Infusion Supplied

• Supplied in 50, 100, 250, 500, and 1000 mL bags

• Sterile saline for irrigation should not confused with that designed for IV administration

Crystalloid Infusion Dose

• To keep vein open (TKVO)

  • Adult: 75 mL/h

• Maintenance

  • 4-2-1 rule

    • For the first 10 kg of body weight, the rate is 4 mL/kg/h

    • For the next 10 kg of body weight, the rate is

      2 mL/kg/h

    • For the remaining body weight, the rate is 1mL/kg/h

• Bolus

  • 10 or 20 mL/kg/dose depending on situation

Crystalloid Infusion Adverse Effects

• May cause pulmonary, cerebral, or peripheral edema

• Will dilute plasma proteins ( vv COP, vv Hct, vv clotting factors)

• May worsen acidosis

• May cause/worsen hypothermia

Hypertonic Saline

• Concentration greater than [isotonic] of 0.9%

• Typical solutions are 3%, 5%, 7%

  • Higher [Na+] pulls more volume into vascular space

  • Some solutions use particles other than sodium to make hypertonic fluid

Colloids

• Remains intravascular

• May draw fluid from extravascular space

• Contains no electrolytes

• pH Albumin: 7.4

• Is considered a blood product so transfusion consent must be obtained

Albumin

• 5% solution is iso-oncotic and leads to 80% initial volume expansion whereas 25% soultion is hyper-oncotic and leads to 200-400% increase in volume within 30 minutes

• Effect persists for 16-24h

Colloid Indications

• Draw excess extravascular fluid into intravascular space

• Replace low albumin

• May be used in various shock states but new evidence shows no benefit over crystalloid

Colloid Contraindications

• Allergy

• CHF with evidence of volume overload

Colloid Precautions

• Albumin is a blood product

• Use with caution in patients with cardiac and renal disease

• May leak into the interstitium in cases of increased vascular permeability

• No O2 carrying capacity

Colloid Adverse Effects

Albumin

• Anaphylaxis or anaphylactoid rxn

• Infection

• Fluid overload; edema

• Imapired coagulation

Starches

• Anaphylaxis

• Renal dysfunction

• Fluid overload; edema

• Impaired coagulation

PRBC

• Contain red blood cells and 20% plasma

• 200-400 mL/unit

• Expected Hgb increase for each unit infused

• Refrigerated product

• ABO and Rh specific

• Massive transfusion 1:1:1 or 2:1:1

• Treatment of anemia

FFP

• Contains acellular blood components (albumin, clotting factors, fibrinogen, prothrombin)

• 250 mL/unit, 4-6 unit/dose

• Frozen product

• Requires re-warming prior to use

• ABO specific

• Massive transfusion protocol 1:1:1 or 2:1:1

• Replace clotting factors

Platelets

• Contains platelets in small amount of plasma

• 50 mL/unit, 4-6 units/dose

• Stored @ room temp.

• Complex ABO identical or non-identical

• Massive transfusion protocol 1:1:1 or 2:1:1

• Treat thrombocytoposis

Cryoprecipitia

• Made from FFP

  • Contains fibrinogen, factor VIII, factor XIII, Von Willebrand factor

  • 10-15 mL/unit, 10 units/dose

  • Frozen product, must be thawed before use

  • ABO typing preferred but not necessary

PCC

• Prothrombin Complex Concentrates

• Factors II, VII, IX, X and proteins C&S, albumin, heparin, sodium citrate in 4-factor

• Dose is 1000-3000 units (INR dependant)

• Refrigerated product

• No ABO or Rh typing required

• Requires co-administration of Vitamin K

• Used to reverse certain anticoagulents or replace low clotting factors in liver disease

Misc. Blood Products

• Freeze-Dried FFP

  • Easy to store (room temp.), transport, and reconstitutes quickly (3 min. with injectable water) and efficiently

• Granulocytes

• Antibodies

• Immune globulin

Hemolysis

• Blood group incompatibility

• Causes hemolysis (destruction) of RBCs

• S/S

  • Fever

  • Chills

  • Back/chest pain

  • Dyspnea

  • Hypotension

  • Hemogloniuria

Erythroblastosis Fetalis

• Rh incompatibility between mom and fetus

• Occurs when mom is Rh neg. with anti-Rh antibodies and fetus is Rh pos

• Causes massive hemolysis in fetus

• Requires prior sensitization

• Rhogam immune globulin can prevent tantibody development if given during pregnancy

Transfusion-Related Lung Injury (TRALI)

• Transfusion Reactions

• Etiology not well understood; appears to be antibody or neutrophil related immune response

• Risk factors include any direct lung injury, sepsis, pancreatitis, shock, overdose, major trauma

• S/S

  • Acute onset severe dyspnea (<6h)

  • ARDS (acute respiratory distress syndrome)

  • No evidence of fluid overload

Transfusion-Related Circulatory Overload (TACO)

• Transfusion Reactions

• Poor heart function or rapid rate/volume of transfusion can cause fluid volume overload

• S/S:

  • Dyspnea, hypertension, cyanosis, tachycardia, increased venous pressure, pulmonary edema

• Treatment:

  • Slow or stop transfusion

  • O2

  • Diuresis

Fever/Allergy/Anaphylaxis - Transfusions

• Transfusion Reactions

• Related to cytokines or other unfiltered proteins or drugs in plasma

• S/S:

  • Fever and chills

  • Urticaria (hives) or full-blown anaphylaxis

Infection - Transfusion

• Transfusion Reactions

• Contaminated blood product (viral or bacterial)

• Causes bacteremia/sepsis in recipient

• S/S:

  • Consistent with sepsis

• Treatment:

  • Stop the transfusion

  • Antibiotics/antivirals

  • Treat hypotension