Hemostasis

Question 1

Hemostasis can be achieved by:

Answer 1

– Clot formation or vessel spasm
– Mechanical pressure
– Ligation
– Hemostatic agents
– Thermally

Question 2

Hemostatic Process

Answer 2

. When a vessel is
injured
– Vasoconstriction begins
. Platelets adhere to
vessel walls
. Platelets release
epinephrine, serotonin
& ADP (adenosine
diphosphate)–causes
more platelets to clump
. ADP causes more platelets to adhere
. Platelet aggregate forms
. Permanent thrombus forms after clotting factor reaction (Prothrombin –
thromboplastin = thrombin – fibrinogen = fibrin)

Question 3

Control of bleeding during
surgery

Answer 3

. 50% of post operative bleeding is from
poor hemostasis
. Key to proper hemostasis
– Gentle tissue handling
– Proper closure without dead space
– Proper wound dressing

Question 4

Methods of Hemostasis: Intraoperative

Answer 4

. Clamps
- Used to compress the
walls of vessels
- Used for grasping
tissue
- Most common is the
hemostat
. Ligature “ties”
- Stick ties
- Use the smallest
diameter possible
. Clips: used in
place of sutures
– Occlude vessels
when applied
. Sponges: Used to apply
pressure
- Absorb excess blood: Laps, Rey-tecs &Patties
. Suction
. Pledgets: For bleeding through needle holes in vessel anastomosis
- Small squares of Teflon
- Sewn over the hole
- Exerts outside pressure
to seal off oozing blood
. Thermal: Electrocautery, Laser, Harmonic Scalpel
. Pharmacologic agents:
- Bone Wax
- Absorbable gelatin
(Gelfoam)
- Collagen (Avitene)
- Oxidized Cellulose (Surgical; nu-Knit)
- Silver Nitrate
- Epinephrine
- Thrombin

Question 5

Postoperative Hemostasis: Drains purpose

Answer 5

Drains
– To remove blood and body fluids
– Prevents dead space
– Prevents edema and hematoma formation
– Helps prevent infection

Question 6

Postoperative Hemostasis: Pressure Devices purpose

Answer 6

Pressure devices
– Application of external pressure
– Occludes vessel until clot has time to form

Question 7

Pharmacologic agents:

Answer 7

. Bone Wax: Made of refined
sterile beeswax
- Used on edges of cut bones
- Mechanical barrier
. Absorbable gelatin (Gelfoam)
– Fibrin is deposited
assisting in clot formation
. Collagen (Avitene)
– Assist in clot formation
. Oxidized cellulose
(Surgicel; nu-Knit)
– Rapid clotting of blood
. Silver nitrate
– Caustic (able to burn
or corrode organic tissue by chemical action)
. Epinephrine
– vasoconstrictor
. Thrombin

Question 8

what is Epinephrine?

Answer 8

– vasoconstrictor

Question 9

Four main blood types:

Answer 9

A - Naturally produce anti-B agglutinins
B - Naturally produce anti-A agglutinins
O - Naturally produces both A and B agglutinins
AB - Produce neither antibody (Universal recipients)

Question 10

At what temp. does blood have to be stored at?

Answer 10

Stored in a refrigerator ( 1-6 C or 33.8-43.8F)

Question 11

Auto transfusion

Answer 11

Preferable – eliminates danger of incompatibility
- Uses own patient’s
blood
- Cell saver

Question 12

Hemolytic Transfusion Reactions

Answer 12

. If blood is not properly matched hemolytic anemia may develop
– Rh incompatibility
– Mismatched
– Can be fatal

Question 13

Homologous

Answer 13

plasma is collected from a single donor

Question 14

Autologous

Answer 14

Plasma is collected from a patient (donor)