Hemostasis
Defined
• Stopping or arresting the loss of blood or
hemorrhage
Coagulation
• Vessel or tissue injury results in:
• Process of coagulation or clot formation to
achieve natural hemostasis in the body
• Body does this to prevent fluid loss which
can cause hypovolemic shock untreated
Injury Intended or Not
1. Smooth muscle contracts and causes
vasoconstriction
2. Clotting process begins
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Some clotting factors ready
Some clotting factors come from damaged
tissue
Some clotting factors come from platelets
Clotting process
• Platelets rush to site and release chemical
thromboplastin
• Prothrombin comes from the liver and is floating in the
bloodstream prothrombin becomes > thrombin
• Fibrinogen is floating in the bloodstream and is
activated by thrombin and creates > fibrin
• Fibrin is like a log with glue on it (whatever touches it
sticks to it, (RBC, WBC, Plts,) = CLOT
• Ca++ (calcium) acts as a co-factor in the clotting
process
Clotting Process
• Platelets>thromboplastin>prothrombin>
thrombin>fibrinogen>fibrin
Dealing with Clotting Process
• Two options:
• Prevent bleeding by enhancing clotting process by other
means
– Hemostatics
• Accelerate or enhance clotting process
• Three types: mechanical, thermal, chemical or pharmacological
– Systemic coagulants
• Calcium salts, vitamin K, platelets or plasma administration
• Prevent clotting altogether to prevent thrombus formation
during some surgeries
– Anti-coagulants (Heparin (IV or parenteral)
– Will have to be reversed after procedure completed (protamine
sulfate, vitamin K or calcium)
Types of Hemostasis
• Mechanical
• Thermal
• Pharmacological or Chemical
Mechanical
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Clamp
Clips
Ligature (ties or suture)
Sponges
Pledgets
Bone wax
Suction
Drains
Pressure device (tourniquet)
Thermal
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Electrocautery
Laser
Harmonic scapel
Cryotherapy
Chemical or Pharmacological
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Gelatin (Gelfoam)
Collagen (Avitene)
Oxidized cellulose (surgicel)
Silver nitrate
Epinephrine (vasoconstrictor)
– Typically an additive to local anesthetics
• Thrombin
Blood loss
• Monitored to determine transfusion needs
• EBL = estimated blood loss
• STSR and circulator’s responsibility to monitor at
all times
• Determine how much irrigant you have used and
subtract that amount from the amount of bloody
fluid in the suction container to determine actual
blood loss
• This information is reported to anesthesia who
will consult surgeon to determine blood
replacement therapy
Transfusions
• Autologous
– self donated previously prior to surgery
• Homologous
– donated from another
Blood types and groups
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Blood types:
A
B
O
AB
Based on presence of
A or B antigen on
surface of RBC
• Rheses factor (RH
factor):
• Rh postive
• Rh negative
• Based on presence of
Rh antigen on surface
of RBC
– Have +
– Don’t have -
Antigens are proteins that set up antibody reaction
Antibodies are proteins that respond to specific antigens
A
AB and Rh antibodies
B
A+
B-
B+
B antibodies A and Rh antibodies
A antibodies
Rh
AB
AB
AB-
B
Rh antibodies
AB+
AB
AB
A
NO antibodies
O-
O+
A, B, Rh antibodies
A, B antibodies
Blood Replacement
• Verification must be performed by two
RNs or an RN and a physician
• Facility policies do not allow for non-RN or
non-physicians to check or verify blood in
Western North Carolina hospitals