Hemostasis Flashcards
What is hemostasis?
spontaneous physiological defense mechanism to stop hemorrhage
What does hemostasis depend on?
vascular, extravascular and intravascular factors
What is the end product of hemostasis?
an effective thrombus
What is surgical hemostasis used for?
used to augment, faility or bypass physiological clotting
What is the goal of surgical hemostasis?
to reduce blood loss and resultant complications
What are 4 issues with surgical bleeding?
- obscures surgical field, reducing accuracy and efficiency
- blood on field, gloves, drapes, instruments is ideal medium for bacterial growth
- extravated blood has negative effects on body
- severe or prolonged hemorrhage may result in shock, hypoxemia, death
What are the problems caused by extravasated blood in the body?
- irritates tissues
- prevents coaptation of wound edges
- delays healing
- encourages infection
- promotes intraabdominal adhesions
What is primary hemorrhage?
occurs immediately after disruption of blood vessels
occurs during surgical dissection
How do you minimize primary hemorrhage?
know anatomy–ligate vessels
traverse one tissue plane at a time
apply tension in tissue handling?
What is delayed hemorrhage?
(intermediate) within 24 hours of injury
(secondary) >24 hours of injury
What is delayed hemorrhage often caused by?
often caused by ineffective treatment of primary hemorrhage
- slipped ligatures
- necrosis of ligated or cauterised vessels
What is the use of hemostatic forceps?
can be used to clamp vessels that will not be repaired. crushing the vessel stops hemorrhage and damages vessel wall, activating clotting.
only for small vessels
What hemostatic forcep is used for a wound?
- smallest forceps capable of achieving hemostasis
2. curved hemostats improve visibility
How do you apply hemostatic forceps to stop bleeding?
- grip in dominant hand with wide based tripod grip
- small superficial bleeders point the tip towards the vessels
- for deep bleeders, large vessels or pedicles apply hemostasis with convex surface facing end of vessel
How do you apply hemostatic forceps to stop bleeding?
- grip in dominant hand with wide based tripod grip
- small superficial bleeders point the tip towards the vessels
- for deep bleeders, large vessels or pedicles apply hemostasis with convex surface facing end of vessel
- for large vessels use jaw rather than tip
- for large pedicles clamped with a carmalt or similar to minimize slippage
What are the most secure methods for hemostasis?
vascular clips and ligatures
What is an advantage of vascular clips and ligatures?
they are less likely to slip than a clot is to be dislodged
What is a disadvantage of vascular clips and ligatures?
foreign material is left in the wound
How do you apply vascular clips?
- dissect vessel free from the surrounding tissue
- diameter of vessel between 1/3-2/3 the length of the clip
- apply several mm from cut end of vessel
- clip artery and vein separately
What are the advantages of vascular clips?
- can be placed more rapidly than ligatures
2. good for poorly accessible locations
What is a disadvantage of vascular clips?
more likely to be dislodged during surgical manipulation
What is the most commonly used method of hemostasis?
ligatures