Lecture 6b: Needle Selection & Suture Patterns

selection of needle depends on:

• type of tissue to be sutured

• topography of the wound

• characteristics of the needle

most surgical needles are made of what? & why?

stainless steel wire because it is

• strong

• corrosion free

• does not harbor bacteria

surgical yield:

the amount of angular deformation a needle can withstand before becoming permanently deformed

ductility:

the needle’s resistance to breaking under a specific amount of bending

sharpness

is related to the angle of the point and the taper ratio of the needle (the sharpest needles have a long, thing, tapered point with smooth cutting edges)

A. basic components of needle

B. types of eyed needles

C. shapes and sizes of needle bodies

selecting a curved needle

depth and diameter of wound are important in selection

¼ circle needles are primarily used in opthalmic procedures

which types of needles are most commonly used in veterinary medicine?

3/8 and ½ curcle needles

a one-half circle or 5/8 circle needles, despite requiring more pronation and supination of the wrist, are easier to use where?

in confiend locations than a 3/8 curved needle

detail of surgical needle points

Suture patterns can be classified as:

interrupted or continuous by the way they appose tissue

• appositional = one tissue edge apposed to another

• everting = turn the tissue edges outward, away from the patient and toward the surgeon

• inverting = turn tissue away from the surgeon, or toward the lumen of a hollow viscous organ

or by which tissues they primarily appose

• SQ

• Subcuticular/intradermal

point of subcutaneous sutures

• eliminate dead space

• provide some apposition of skin so that less tension is placed on skin sutures

• generally, are placed in a simple continuous manner

  • in some instances, such as when draining might be necessary, simple interrupted sutures are preferable

subcuticular sutures may be used in palce of:

skin sutures

• reduce scarring

• eliminate the need for suture removal

suture line is begun by burying the knot in the dermis and then suture is advanced in the dermal tissue, bites are parallel to the long axis of the incision, suture line is completed with a buried knot, no suture is visible externally when complete, absorbable suture materials with a cutting edge are preferred in which suture pattern?

subcuticular sutures

subcuticular vs subcutaneous

list of interrupted suture patterns:

• simple interrupted

• horizontal mattress

• cruciate

• vertical mattress

• halstead

• gambee

simple interrupted suture patternare made by:

inserting the neelde through tissue on one side of an incision or wound, passing it to the opposite side, and tying

• knot is offset so that it does not rest on top of the incision

• ends of the suture are cut (for skin sutures, the ends are left long enough to allow them to be grasped during removal)

Simple interrupted suture pattern

• sutures should be placed approx 2 to 3mm away from skin edge

• right-handed surgeons place sutures from right to left in a horizontal fashion. Left-handed are opposite

• (dominant to nondominant!!)

simple interrupted sutures are:

appositional (unless excessive tension is applied)

primary advantages and disadvantages of simple interrupted sutures is that:

disruption of a single suture does not cause the enture suture line to fail

however they take more time than continuous patterns

result in more foreign material (knots) in the wound

horiztonal mattress suture pattern are used primarily:

in areas of tension

• can be placed rapidly

• often cause tissue eversion (care should be exercised to appose, rather than evert, tissue margins)

• suture should be angled though the tissue so that it passes just below the dermis

• generally, are separated by 4 to 5 mm

• can be bolstered using rubber stents and buttons

cruciate suture pattern

• formed when 2 simple interrupted sutures are placed parallel to each other and then tied across the incision to create an X

• appositional

• can relieve low to moderate tension across an incision

• less suture material is used to close a skin incision than with simple interrupted

• affords the security of an interrupted pattern

A. Simple interrupted

B. Horizontal mattress

C. Cruciate

Vertical mattress suture pattern

• stronger than horizontal mattress sutures

• preferred when addressing tension in skin closure

• less disruption to the blood supply of the wound edges

• each bite approx 4 mm from skin edge

• relatively time consuming

• eversion of skin margins is less of a proglem than with horizontal mattress sutures

• can be bolstered using rubber stents and buttons

stents

placing padded material beneath the suture loops is stenting

halstead suture pattern

an interrupted mattress pattern that is a modification of a continuous Lembert pattern

• infrequently used in vet med

• provides exact skin approximation

Gambee suture pattern

• interrupted pattern used in intestinal surgery to reduce mucosal eversion

• also reduces mucosal inversion and may reduce wicking of material from the intestinal lumen to the exterior

D. Vertical mattress

E. Halsted

F. Gambee

Continuous suture patterns

• simple continuous

• running

• ford interlocking

• Lembert

• Connel

• Cushing

simple continuous pattern

• consists of a series of simple interrupted sutures with a knot on either end

• provides maximum tissue apposition

• relatively air and fluid tight compared with series of simple interrupted sutures

• frequently used to close the linea alba and subcutaneous tissue

• care should be taken when placing continuous suture lines in areas where tightening of the suture may result in purse-string like effect (such as with an intestinal anastomosis)

A. Simple Continuous

B. Running

We won’t be performing at LMU really!!

simple continuous suture pattern, how is the needle passed?

rthe suture is advanced above the incision line at a diaganol

running suture

a running suture is created if the suture is advanced above and below the incision line, but this is not as secure as less tissue is purchased

running:

• created much like simple continuous, but the suture is advanced above and below the incision line

• it is not as secure as a simple continuous since less tissue is purchased

simple continuous

• needle passed through the tissue from one side to the other, perpendicular to the incision

• the suture is advanced above the incision line at a diagonal

Ford interlocking pattern

• Modification of a simple continuous pattern

• Each passage through the tissue is partly locked

• Each pass through the tissue is linked to the previous passage as the suture exits the tissue through a created loop of material

• May be placed quickly

• May appose tissue better than a simple interrupted pattern

• Provides greater stability than a simple continuous pattern in the event of a partial break along the line

• Larger amount of suture material is used

• Sutures may be more difficult to remove

ford interlocking suture pattern

place from nondominant to dominant hand for a right-handed surgeon (only pattern like this!)

Lembert suture pattern

• a variation of a vertical mattress pattern applied in a continuous fashion

• inverting pattern that often is used to close hollow viscera

Cushing and Connell suture pattern

• Inverting patterns that are used to close hollow organs

• Watertight seal is created by the inversion

• Patterns are similar, except that a Connell pattern enters the lumen, whereas a Cushing pattern extends only to the submucosal layer

• It was previously thought that a Cushing pattern would be preferable to a Connell for cystotomy closure because suture material in the lumen might be calculogenic; however, the use of rapidly absorbed monofilament sutures negates this concern

D. Lembert

E. Connell

F. Cushing

Parker-Kerr Oversew

• 2-layer closure for inverted closure of a transected, clamped, stump of hollow viscera

• begins with Cushing/Connell, followed by an inverting seromuscular pattern

• seldom used because it causes excessive tissue inversion

Parker-Kerr Oversew

Tendon Sutures

• specific suture configurations are used to approximate severed ends of a tendon or to secure one end of a tendon to bone or muscle

  • Kessler locking-loop

  • Bunnel-Mayer

  • Krackow

  • Three-loop pulley

Tendon sutures (cool)