Exam 2 Labs Flashcards
True or false: Extra ties add strength to a suture knot.
FALSE - however, more throws are needed with larger sized suture
What is the minimum amount of throws needed for a secure knot?
4 throws (2 knots)
How should tissue be apposed?
only appose like tissue - if unlike tissues are apposed, there will be a delay in healing +/- dishiscence
Why is it important to close dead space?
minimizes the risk of seroma formation
Why aren’t sutures placed too tight?
there is bound to be incision edge swelling after surgery
What is a square knot?
2 simple throws applied in opposite directions using even tension on both strands of suture while tightening each throw
- secure = 2 square knots (4 throws)
When is a surgeons knot used? How does it compare to the square knot? How is it done?
when there is tension on tissues
greater knot security (still not bulky) with an increased friction to keep it from slipping
- extra suture material can make it harder to tighten
double twist on first throw (suture wrapped around jaws of needle driver twice) followed by 2-3 square knots
Where should the first and last bites be taken with respect to the incision?
3-5 mm away from edge of incision
What are psychomotor skills?
movement tasks that require both cognitive and motor processes —> learned motor skills that are performed without conscious thought
How are ringed instruments handled? Why?
wide-base tripod grip with thumb and ring finger in the rings up to the first knuckle and pointer finger along the shank
- increases stability
- balances instrument
- atraumatic tissue handling
- efficient suturing and securing knots
Ringed instrument anatomy:
How should suture needles be held by the needle drivers?
2/3 from point
1/3 from swagged end
How should thumb forceps be handled?
pencil grip between thumb and pointer finger (+/- middle finger)
How are thumb forceps help in the resting position?
“finger guns”
What are the 2 ways to hold scalpel blade holders?
- pencil grip - fine, short, precise incisions
- fingertip/slide grip - long incisions
How are scalpel handles armed?
How are scalpel blades unarmed?
What 4 things affect knot security?
- size and suture material
- length of cut ends (ears/tags)
- quality of knot
- knot and suture patter chosen
Is a simple knot (1 throw) by itself secure?
NO - incomplete basic unit
Surgical knot:
What makes a secured knot?
placing a minimum of 2 additional simple throws on top of the initial knot (4 total throws)
Why are hand ties important? What is a disadvantage compared to instrument tying?
useful in confined spaces where surgical tools cannot fit
uses more suture material
How do 1 hand ties and 2 hand ties compare?
1 - useful in deep cavities and confined spaces
2 - allows for good control and accuracy, but can be difficult in confined spaces
What is a half hitch knot?
AKA: slip knot
occurs when there is UNEVEN tension on suture strands when tightening the knot or when upward tension is applied to one strand
What is a granny knot?
type of slip knot where a second throw is tightened in the same direction as the first throw resulting in poor knot security
What are 2 possible causes of knot failure?
- knots slip - poorly ties
- suture breakage
(sutures tend to fail at the knot unless suture has been damaged)
What are ligatures? In what 3 situations is this common?
suture is used to tie off (ligate) an anatomical structure to aid in hemostasis
- ovarian pedicle (spay)
- testicular pedicle (neuter)
- ligation of blood vessels
How does chance of ligature failing compare to the volume of tissue it encloses?
proportionally
- more tissue = higher chance to fail or slip
What is the circumferential ligature? Where is it placed? When is it often performed?
suture is wrapped around vessel/pedicle and secured by tying a square or surgeons knot
placed PROXIMALLY on the pedicle (closest to the body)
in the “crush” of a clamp
When is the transfixation/transfixing ligature used? Where is it typically placed?
larger vessels or pedicles - 2 steps, 2 knots
placed DISTALLY on the pedicle and DISTAL to circumferential ligature (further away from the body)
Testicular ligation:
In what 2 situations are friction knots helpful for ligatures? Why are they so commonly used? What are the main 2 examples?
- fatty pedicles (spay) or pedicles under tension
- vascular ligation (spay/neuter)
greater knot security compared to circumferential and transfixing ligatures
Miller’s and modified Miller’s knots
Miller’s knot:
Modified Miller’s knot:
AKA strangle knot
What is a crush?
hemostat is placed on pedicle or vessel and used to crush tissue, then removed and replaced by ligature
What is flashing?
hemostat is placed on a pedicle or vessel and then loosened while the first 2 thors of ligature are placed
