DEPARTMENT OF ANESTHESIA
UNIVERSITY OF MANITOBA
Fluid Therapy Training Module for
Para Professional Personnel
Preamble
The Department of Anesthesia at the University of Manitoba is committed to the
promotion of patient safety and quality of care. Education of providers of primary and
resuscitation support from all disciplines is a fundamental part of that mission. For this
educational effort to be effective, it is important to consider and incorporate the particular
needs of each group for whom skills development is contemplated. This document
outlines the structure, and goals and objectives of a program designed to meet the
developmental needs of paramedical personnel providing care for patients with respect to
fluid management in resuscitation.
Program Outline
Each trainee will be provided with a program outline, including a reference manual,
orientation and contact information, and evaluation logs. At the end of the rotation, the
trainee will be expected to keep evaluation logs and provide them to the Coordinator of
the sponsoring program as proof of completion of the educational program.
The trainee will present to the assigned hospital OR suite on the first day of the rotation,
at the time and place indicated in the orientation manual. The senior resident or site
coordinator will direct the trainee to a primary staff person. This primary staffperson
shall
Review the educational material with the trainee
Provide resource discussion
Evaluate the degree to which the trainee has met the knowledge objectives
Record the results of that evaluation on the evaluation log
Coordinate access to vascular access techniques with him/herself, and other staff
as available
Each individual staff physician or resident who supervises vascular access techniques
will
Observe the trainee and provide formative feedback
Evaluate the trainee’s competence with the technique
Record the evaluation on the provided log
As applicable review and evaluate elements of the curriculum as discussed with
the primary mentor
Goals and Objectives
By the end of this rotation, the trainee will be able to:
Describe the indications for, contraindications to and complications of
o Blood product therapy
o Colloid therapy
o Crystalloid therapy
Describe the differences between colloid, crystalloid and blood component
therapy
Select and perform appropriate vascular access for patients requiring stabilization
Recognize complications of vascular access techniques
Assess fluid status and quantify need for fluid administration
Evaluation Log for Paramedical
Fluid Therapy Training Module
Major Minor No Complete Outstanding
Cognitive Objectives Omissions Omissions Omissions Discussion
Describes the indications for, contraindications to
and complications of
o
o Normal saline
o Non-blood colloid
o Matched Red Cells
o Emergency red cells
o Central venous access
Correctly assesses fluid status
Correctly quantifies need for fluid therapy
Describes the appropriate technique for central
venous access
Performs peripheral venous access
Identifies complications of central or peripheral
venous access
Describe the correct interpretation of information
from a pulse oximeter, including sources of error
Major Minor Competent Efficient Outstanding
Technical Skills Objectives Errors Errors technique technique
IV #1
IV #2
IV #3
IV #4
IV #5
IV #6
IV #7
IV #8
IV #9
IV #10
BLOOD AND FLUID COMPONENT THERAPY
Stephen Kowalski, MD, FRCPC
Rob Brown, MD, FRCPC
Rational fluid therapy is dependent upon an appropriate understanding of the normal
physiology of body fluids. Essentially, the body is divided into two major fluid
components: 1) Intracellular fluid, and 2) Extracellular fluid. Although these compartments
are separated by membranes of varying types, water, oxygen, electrolytes and nutrients cross
these membrane barriers according to electrical, osmotic or chemical gradients. In order to
preserve cell viability, each compartment maintains a fluid environment that allows cellular
function to occur efficiently.
Water accounts for 45 to 50 percent of the body weight of adult females and 55 to 60
percent of the body weight in adult males. The lower water content in females is due to
their increased percentage of adipose tissue, which contains less water than muscle. Water
content decreases with age. Newborn infants have 75 to 85% of their body weight as water.
This decreases to 65% by age 1 and continues to decrease gradually after adolescence.
Total body water is distributed between two major fluid compartments: 1) The extracellular
fluid includes both the interstitial and the circulating blood volume, which accounts for 20%
of body weight while, 2) The intracellular fluid accounts for 40% of the body weight. (Table
1)
TABLE 1
WATER DISTRIBUTION (70 KG MALE)
WATER COMPARTMENT %BODY WEIGHT VOLUME
Extracellular: 20% 14.0 L
- Blood Volume 6% 4.2 L
- Interstitial Fluid 14% 9.8 L
Intracellular: 40% 28.0 L
h
TOTAL 60% 42.0 L
The movement of water between different fluid compartments is determined by two
forces: 1) hydrostatic pressure, and 2) osmotic pressure. Water moves from a compartment
with a high hydrostatic pressure to a compartment with a low hydrostatic pressure.
However, osmotic forces are the prime determinant of water distribution in the body. The
osmotic pressure of a solution or compartment is proportional to the "number of molecules"
in a solution. Since water can freely cross all cell membranes, the body fluids are in osmotic
equilibrium as the osmolalities of the intracellular and extracellular fluids are the same.
Consequently, both the actual volume and the distribution of the body water between the
cells and the extracellular fluid is determined by the number of osmotically active particles
in each compartment. Sodium (Na+) is the principle electrolyte that acts to hold water in the
extracellular space. Potassium (K+) performs a similar function in the intracellular
compartment. Although the cell membrane is permeable to both Na+ and K+ these ions are
able to be effective because they are restricted to their respective fluid compartments by the
Na+/K+ pump in the cell membrane. In contrast, larger molecules such as plasma proteins
do not cross cell membranes easily and are "confined" to the circulating blood volume.
Therefore plasma proteins although they constitute only a small fraction of the total number
of dissolved particles in the plasma, represent a major osmotic force preventing excessive
fluid loss from capillaries. This effect of the plasma proteins (particularly albumin) is called
the oncotic pressure.
During a normal day, water intake equals water output. Most of water output
involves "obligatory" losses from three sources (Table 2): 1) the skin and respiratory tract,
2) urine, and 3) stool. "Insensible" water loss by vaporization from the skin and lungs is
approximately 12-15 ml/kg or about 900 ml per day in a 70 kg man. Insensible losses can
be increased 10% per degree C rise in body temperature, by ventilation with dry anesthetic
gases and active sweating. Urinary losses average 1 ml/kg/hr or 1600 ml in a 70 kg male
while fecal loss is less than 100 ml/24 hour period (Table 2). The replacement of these
water losses can be termed "maintenance" fluids.
TABLE 2
WATER LOSS PER DAY (70 KG MALE)
1) INSENSIBLE
a) Perspiration 600 ml
b) Lungs 400 ml
2. URINE 1,500 ml
3. FECES 100 ml
TOTAL 2,600 ml
Under normal circumstances, daily water losses are not associated with loss of
electrolytes. However, gastric suction, vomiting, bowel obstruction, and diarrhea may be
associated with significant electrolyte losses, which must be replaced in addition to water
replacement. Typical electrolyte contents of various body fluids are included in Table 3.
Therefore, replacement fluids should be selected on the basis of quantitative water loss and
qualitative electrolyte loss.
TABLE 3
+
FLUID Na (mEq/L) K+(mEg/L) Cl-(mEq/L) HCO3-(mEq/L)
Gastric Juice 60 9 84 0
Bile 149 5 101 45
Pancreatic Juice 141 5 77 92
Ileal Fluid 129 11 116 29
Cecal Fluid 80 21 48 22
Several prepared solutions are outlined in Table 4. In the operating room, fluid
replacement is directed at replacing: 1) maintenance fluid requirements, 2) third space losses
(edema, exudates, transudates, ascites), and 3) blood. After replacing the pure water loss
that has occurred when the patient is fasting before surgery, a balanced electrolyte solution
(5% D N/S; Ringer's Lactate; 5% D, 1/2 N/S) should be used to replace both maintenance
fluid requirements and third space losses. Approximate fluid volume can be administered
according to the following guidelines:
4 ml/kg/hr - Baseline Maintenance Requirements.
6 ml/kg/hr - Minimal Surgery (ex. squint repair).
8 ml/kg/hr - Moderate Surgery (ex. hernias).
10-12 ml/kg/hr - Extensive Surgery (ex. thoracotomy, bowel obstruction).
The final category of fluid management during surgery is the replacement of blood
and blood products. Blood has several important components:
1. Volume is necessary to maintain blood pressure and to provide adequate tissue
perfusion to all organs. Approximations of circulating blood volumes are: Newborn
85 ml/kg; Adult Male 65 ml/kg; and Adult Female 60 ml/kg.
2. Hemoglobin which is vital for the transport of oxygen.
3. Platelets and coagulation proteins which are necessary for hemostatis.
4. Plasma proteins which supply the oncotic pressure for proper water balance between
the extracellular and intracellular fluid compartment. The following is a summary of
some of the blood products that are currently available. It should be remembered
that almost all blood products are stored at 4oC and should be warmed and filtered
before administration to patients.
TABLE 4
RINGER’S NORMAL
LACTATE SALINE 5% D1/2 N/S 1/3D, 2/3, N/S
+
Na 130 154 77
K+ 4 - -
Cl- 109 154 77
Ca++ 3 - -
Lactate 28 - -
PH 6.5 5.5 4.0
Dextrose - - 5.0 g/100 ml 3.3 g/100 ml
Calories/L - - 200/L 132/L
Osmol 272 308 406 269
Packed Red Blood Cells
The volume of packed red blood cells is approximately 250-300 ml/unit. Since the
hematocrit is 55%, packed cells are very viscous which makes them difficult to transfuse
rapidly. This property makes packed cells more effective in treating chronic anemias than
rapid blood loss. In emergencies, the viscosity may be reduced which will allow for more
rapid administration by adding either 200 ml of normal saline or one unit of fresh frozen
plasma. In order to raise the hemoglobin 1 gram (or 10 gm/dl), 3 ml/kg of packed cells or 6
ml/kg of "reconstituted" packed cells may be transfused. Packed cells may transmit
hepatitis but do not contain platelets, coagulation proteins or albumin.
Fresh frozen plasma/stored plasma. The volume of frozen plasma is approximately
200 ml/unit. Plasma contains both coagulation factors and plasma proteins. Fresh frozen
plasma contains the labile clotting factors (Factors V and VIII) while stored plasma contains
reduced amounts of these clotting factors. Most plasma used in operating rooms is stored
plasma. Plasma is labelled for ABO but not usually for RH group. Plasma must be
compatible with the recipient's blood but it is not necessarily group specific. (see Table 5)
TABLE 5
BLOOD GROUPS OF PLASMA THAT MAY BE INFUSED INTO RECIPIENTS
RECIPIENTS BLOOD GROUP DONOR BLOOD GROUP
0 0, A, B, AB
A A, AB
B B, AB
AB AB
Stored plasma is effective in treating patients requiring volume expansion and
protein replacement while fresh frozen plasma should be administered to patients with
coagulation abnormalities. Plasma does not contain platelets and may transmit hepatitis and
other viruses (HIV).
Platelets
The volume of platelet concentrates is approximately 50 ml/unit. Unlike plasma and
packed red blood cells, platelets cannot be stored for long periods of time and must be
administered within 72 hours of collection. They are stored at 22oC with continuous gentle
agitation. Each unit contains 60% of the functional platelets found in a unit of fresh whole
blood. Platelet concentrates are reserved for the treatment of thrombocytopenia and serum
levels of 50,000 mm3 should be present to prevent bleeding during major surgery. Six units
of platelets will raise the platelet count by 30,000 in a 70 kg male. Platelet concentrates may
transmit hepatitis and other viruses.
Cryoprecipitate
The volume in cryoprecipitate is 5-15 ml/unit. Cryoprecipitate is essentially a
concentrate of factor VIII and is effective in treating hemophilia. The administration of 1
unit/6 kg body weight will raise the factor VIII level 15-20%. It is usually administered
every 8 hours due to the 1/2 life of factor VIII. Cryoprecipitate can transmit hepatitis and
other viruses.
Albumin
Albumin is available in concentrations of 5% and 25%. The 5% solution is supplied
in 50 ml, 250 ml, and 500 ml volumes and is osmotically equivalent to an equal volume of
normal plasma. The 25% solution is available in volumes of 20 ml, 50 ml, and 100 ml and
is osmotically equivalent to five times its volume of plasma. Albumin is used as a volume
expander or to replace protein loss as occurs with an extensive burn or ascites. Albumin is
pasteurized and does not transmit hepatitis or HIV.
Pentastarch
Pentastarch is a synthetic solution. It is a hydroxyethyl starch derived from
cornstarch which is prepared commercially as a 10% solution dissolved in normal saline.
Pentastarch is a large molecule (average molecular weight 200,000 to 300,000) and was
developed as a substitute for albumin. It is supplied as a 250 ml and 500 ml bags for
intravenous infusion. It is slightly more osmotically active than an equivalent volume of 5%
albumin. Pentastarch does not cause coagulation abnormalities that are seen with other
synthetic plasma volume expanders such as hetastarch and dextran.
In summary, the goal of fluid therapy during surgery is to maintain homeostasis.
Since the patients are unconscious, the Anesthesiologist must replace both maintenance
water and electrolyte losses. Third space and blood losses represent additional fluid
replacement that must be individualized. This chapter has suggested "guidelines" for
optimal fluid replacement during surgery. However, the absolute amount and type of
solution used during surgery must be modified by clinical examination of the patient.
Therefore the ultimate goal of fluid therapy is not to comply with the guidelines of fluid
administration, but to preserve cardiovascular stability, adequate perfusion and urine output.
Fluid therapy must be individualized for each patient, with consideration of the functional
status of most organ systems and based on accepted principles of basic science and
physiology.