2. Total Body Water (TBW)
• Varies with age, gender
• 55% body weight in males
• 45% body weight in females
• 80% body weight in infants
• Less in obese: fat contains little water
3. Body Water Compartments
• Intracellular water: 2/3 of TBW
• Extracellular water: 1/3 TBW
- Extravascular water: 3/4 of extracellular water
- Intravascular water: 1/4 of extracellular water
6. Crystalloids
Crystalloid
Solutions that contain small molecules that flow easily across
the cell membranes, allowing for transfer from the bloodstream
into the cells and body tissues.
This will increase fluid volume in both the interstitial and
intravascular spaces (Extracellular)
It is subdivided into:
* Isotonic
* Hypotonic
* Hypertonic
7. Crystalloids
When to consider a solution isotonic?
When the concentration of the particles (solutes) is similar to that of
plasma, So it doesn't move into cells and remains within the
extracellular compartment thus increasing intravascular volume.
Types of isotonic solutions include:
-0.9% sodium chloride (0.9% NaCl)
-lactated Ringer's solution
-5% dextrose in water (D5W)
-Ringer’s solution
8. 0.9% sodium chloride (Normal
Saline)
Simply salt water that contains only water,
sodium (154 mEq/L), and chloride (154 mEq/L).
It's called "normal saline solution" because the
percentage of sodium chloride in the solution is
similar to the concentration of sodium and
chloride in the intravascular space
9. When to be given?
1- to treat low extracellular fluid, as in fluid
volume deficit from
- Hemorrhage - Severe vomiting or diarrhea
- Heavy drainage from GI suction, fistulas, or
wounds
2- Shock
3- Mild hyponatremia
4- Metabolic acidosis (such as diabetic
10. Normal saline 0.9%
TAKE CARE:
Because 0.9% sodium chloride replaces
extracellular fluid, it should be used cautiously
in certain patients (those with cardiac or renal
disease) for fear of fluid volume overload.
11. When to be used?
-To replace GI tract fluid losses ( Diarrhea or
vomiting )
-Fistula drainage
-Fluid losses due to burns and trauma
-Patients experiencing acute blood loss or
hypovolemia due to third-space fluid shifts.
12. Notice. Both 0.9% sodium chloride and LR may
be used in many clinical situations, but patients
requiring electrolyte replacement (such as
surgical or burn patients) will benefit more from
an infusion of LR.
13. Dextrose 5%
It is considered an isotonic solution, but when
the dextrose is metabolized, the solution
actually becomes hypotonic and causes fluid to
shift into cells.
It provides 170 calories per liter, but it doesn't
replace electrolytes.
The supplied calories doesn't provide enough
nutrition for prolonged use. But still can be
added to provide some calories while the
patient is NPO.
14. Take Care !
- D5W is not good for patients with renal failure or cardiac problems
since it could cause fluid overload.
- patients at risk for intracranial pressure should not receive D5W
since it could increase cerebral edema
- D5W shouldn't be used in isolation to treat fluid volume deficit
because it dilutes plasma electrolyte concentrations
- Never mix dextrose with blood as it causes blood to hemolyze.
-Not used for resuscitation, because the solution won't remain in the
intravascular space.
-Not used in the early postoperative period, because the body's
reaction to the surgical stress may cause an increase in antidiuretic
hormone secretion
15. Hypotonic solution
Compared with intracellular fluid (as well as compared with
isotonic solutions), hypotonic solutions have a lower
concentration of solutes (electrolytes). And osmolality
less than 250 mOsm/L .
Hypotonic crystalloid solutions lowers the serum
osmolality within the vascular space, causing fluid to
shift from the intravascular space to both the
intracellular and interstitial spaces.
These solutions will hydrate cells, although their use may
deplete fluid within the circulatory system.
16. 0.45% sodium chloride (0.45% NaCl), 0.33%
sodium chloride,
0.2% sodium chloride, and
2.5% dextrose in water
17. Hypotonic fluids are used to treat patients with
conditions causing intracellular dehydration,
when fluid needs to be shifted into the cell ,
such as:
Hypernatremia
Diabetic ketoacidosis
Hyperosmolar hyperglycemic state.
18. Hypertonic Solution
Solution that have a higher tonicity or solute concentration. Hypertonic
fluids have an osmolarity of 375 mOsm/L or higher
The osmotic pressure gradient draws water out of the intracellular space,
increasing extracellular fluid volume, so they are used as volume
expanders.
Some examples and Indications:
1- 3% sodium chloride (3% NaCl):
May be prescribed for patients in critical situations of severe hyponatremia.
Patients with cerebral edema may benefit from an infusion of hypertonic
sodium chloride
2- 5% Dextrose with normal saline (D5NS): which replaces sodium,
chloride and some calories
19. Colloids
It expand the intravascular volume by drawing fluid
from the interstitial spaces into the intravascular
compartment through their higher oncotic pressure.
the same effect as hypertonic crystalloids solutions
but it requires administration of less total volume and
have a longer duration of action because the
molecules remain within the intravascular space
longer.
Its effect can last for several days if capillary wall
linings are intact and working properly.
20. Colloids
Precautions!
Colloid solutions can interfere with platelet function
and increase bleeding times, so monitor the
patient's coagulation indexes.
Anaphylactoid reactions are a rare but potentially
lethal adverse reaction to colloids. Take a careful
allergy history from patients receiving colloids (or
any other drug or fluid), asking specifically if
they've ever had a reaction to an I.V. infusion
22. Perioperative Evaluation
of Fluid Status
• Factors to Assess:
- h/o intake and output
- blood pressure: supine and standing
- heart rate
- skin turgor
- urinary output
- serum electrolytes/osmolarity
- mental status
23. Perioperative Fluid Requirements
The following factors must be taken into account:
1- Maintenance fluid requirements
2- NPO and other deficits: NG suction, bowel
prep
3- Third space losses
4- Replacement of blood loss
5- Special additional losses: diarrhea
24. 1- Maintenance Fluid Requirements
• Insensible losses such as evaporation of water
from respiratory tract, sweat, feces, urinary
excretion. Occurs continually.
• Adults: approximately 1.5 ml/kg/hr
• “4-2-1 Rule”
- 4 ml/kg/hr for the first 10 kg of body weight
- 2 ml/kg/hr for the second 10 kg body weight
- 1 ml/kg/hr subsequent kg body weight
- Extra fluid for fever, tracheotomy, denuded surfaces
25. 2- NPO and other deficits
• Nbm deficit = number of hours Nbm x maintenance
fluid requirement.
• Bowel prep may result in up to 1 L fluid loss.
• Measurable fluid losses, e.g. NG suctioning,
vomiting, stoma output, biliary fistula and tube.
26. 3- Third Space Losses
• Isotonic transfer of ECF from functional body
fluid compartments to non-functional
compartments.
• Depends on location and duration of surgical
procedure, amount of tissue trauma, ambient
temperature, room ventilation.
27. Replacing Third Space Losses
• Superficial surgical trauma: 1-2 ml/kg/hr
• Minimal Surgical Trauma: 3-4 ml/kg/hr
- head and neck, hernia, knee surgery
• Moderate Surgical Trauma: 5-6 ml/kg/hr
- hysterectomy, chest surgery
• Severe surgical trauma: 8-10 ml/kg/hr (or more)
- AAA repair, nehprectomy
28. 4- Blood Loss
• Replace 3 cc of crystalloid solution per cc of
blood loss (crystalloid solutions leave the
intravascular space)
• When using blood products or colloids replace
blood loss volume per volume
29. 5- Other additional losses
• Ongoing fluid losses from other sites:
- gastric drainage
- stoma output
- diarrhea
• Replace volume per volume with crystalloid
solutions
30. Example
• 62 y/o male, 80 kg, for hemicolectomy
• nbm after 2200, surgery at 0800, received
bowel prep
• 3 hr. procedure, 500 cc blood loss
• What are his estimated intraoperative fluid
requirements?
31. Example (cont.)
• Fluid deficit (NPO): 1.5 ml/kg/hr x 10 hrs = 1200 ml +
1000 ml for bowel prep = 2200 ml total deficit:
(Replace 1/2 first hr, 1/4 2nd hr, 1/4 3rd hour).
• Maintenance: 1.5 ml/kg/hr x 3hrs = 360mls
• Third Space Losses: 6 ml/kg/hr x 3 hrs =1440 mls
• Blood Loss: 500ml x 3 = 1500ml
• Total = 2200+360+1440+1500=5500mls
32. Clinical Evaluation of Fluid Replacement
1. Urine Output: at least 1.0 ml/kg/hr
2. Vital Signs: BP and HR normal (How is the patient
doing?)
3. Physical Assessment: Skin and mucous membranes
no dry; no thirst in an awake patient
4. Invasive monitoring; CVP or PCWP may be used as
a guide
5. Laboratory tests: periodic monitoring of hemoglobin
and hematocrit
33. Summary
• Fluid therapy is critically important during the
perioperative period.
• The most important goal is to maintain
hemodynamic stability and protect vital organs
from hypoperfusion (heart, liver, brain, kidneys).
• All sources of fluid losses must be accounted
for.
• Good fluid management goes a long way toward
preventing problems.
34. Transfusion Therapy
- 60% of transfusions occur perioperatively.
- responsibility of transfusing perioperatively is with
the anesthesiologist.
35. When is Transfusion Necessary?
• “Transfusion Trigger”: Hgb level at which
transfusion should be given.
- Varies with patients and procedures
• Tolerance of acute anemia depends on:
- Maintenance of intravascular volume
- Ability to increase cardiac output
- Increases in 2,3-DPG to deliver more of the
carried oxygen to tissues
36. Type and Screen
• Donated blood that has been tested for ABO/Rh
antigens and screened for common antibodies
(not mixed with recipient blood).
- Used when usage of blood is unlikely, but needs to be
available (hysterectomy).
- Allows blood to available for other patients.
- Chance of hemolytic reaction: 1:10,000.
37. Component Therapy
• A unit of whole blood is divided into components; Allows
prolonged storage and specific treatment of underlying
problem with increased efficiency:
- packed red blood cells (pRBC’s)
- platelet concentrate
- fresh frozen plasma (contains all clotting factors)
- cryoprecipitate (contains factors VIII and fibrinogen; used in Von
Willebrand’s disease)
- albumin
- plasma protein fraction
- leukocyte poor blood
- factor VIII
- antibody concentrates
38. Packed Red Blood Cells
• 1 unit = 250 ml. Hct. = 70-80%.
• 1 unit pRBC’s raises Hgb 1 gm/dL.
• Mixed with saline: LR has Calcium which may
cause clotting if mixed with pRBC’s.
39. Platelet Concentrate
• Treatment of thrombocytopenia
• Intraoperatively used if platlet count drops below
50,000 cells-mm3 (lab analysis).
• 1 unit of platelets increases platelet count 5000-
10000 cells-mm3.
• Risks:
- Sensitization due to HLA on platelets
- Viral transmission
40. Fresh Frozen Plasma
• Plasma from whole blood frozen within 6 hours of
collection.
- Contains coagulation factors except platelets
- Used for treatment of isolated factor deficiences, reversal
of Coumadin effect, TTP, etc.
- Used when PT and PTT are >1.5 normal
• Risks:
- Viral transmission
- Allergy
41. Complications of Blood Therapy
• Transfusion Reactions:
- Febrile; most common, usually controlled by
slowing infusion and giving antipyretics
- Allergic; increased body temp., pruritis, urticaria.
Rx: antihistamine,discontinuation. Examination of
plasma and urine for free hemoglobin helps rule out
hemolytic reactions.
42. Complications of Blood Therapy (cont.)
• Hemolytic:
- Wrong blood type administered (oops).
- Activation of complement system leads to intravascular
hemolysis, spontaneous hemorrhage.
- Signs: hypotension,fever, chills, dyspnea, skin flushing,
substernal pain. Signs are easily masked by general
anesthesia.
- Free Hgb in plasma or urine
- Acute renal failure
- Disseminated Intravascular Coagulation (DIC)
43. Complications (cont.)
• Transmission of Viral Diseases:
- Hepatitis C; 1:30,000 per unit
- Hepatitis B; 1:200,000 per unit
- HIV; 1:450,000-1:600,000 per unit
- 22 day window for HIV infection and test detection
- CMV may be the most common agent transmitted, but
only effects immuno-compromised patients
- Parasitic and bacterial transmission very low
44. Treatment of Acute Hemolytic
Reactions
• Immediate discontinuation of blood products
and send blood bags to lab.
• Maintenance of urine output with crystalloid
infusions
45. Administering Blood Products
- Consent necessary for elective transfusion
- Unit is checked by 2 people for Unit #, patient ID,
expiration date, physical appearance.
- pRBC’s are mixed with saline solution (not LR)
- Products are warmed mechanically and given slowly if
condition permits
- Close observation of patient for signs of complications
- If complications suspected, infusion discontinued,
blood bank notified, proper steps taken.
46. Transfusion Therapy Summary
• Decision to transfuse involves many factors
• Availability of component factors allows
treatment of specific deficiency
• Risks of transfusion must be understood and
explained to patients
• Vigilance necessary when transfusing any
blood product