SutureSuture MaterialsMaterials & & TechniquesTechniques

Tying knotsTying knotsIMTCIMTC

International Microsurgical Training CentreInternational Microsurgical Training CentreProf.dr. René RemieProf.dr. René Remie

Dr. Klaas KramerDr. Klaas Kramer

AgendaAgendaImportant factors in surgeryImportant factors in surgeryProperties of suture materialsProperties of suture materials

AbsorbableAbsorbableNonNon--absorbableabsorbableTissue reactionsTissue reactionsNeedlesNeedles

SutureSuture techniquestechniquesSutureSuture--relatedrelated infectionsinfectionsSutureSuture lengthlength toto woundwound lenghtlenght ratioratioHowHow toto tietie a knota knotTakeTake home home messagesmessagesPractical partPractical part

Important factors in surgeryImportant factors in surgery

Basic principlesBasic principlesSurgical protocolSurgical protocolAnatomyAnatomySuture materialsSuture materialsPeriPeri--operative careoperative care

TemperatureTemperatureBody fluidsBody fluids

Basic principles of surgeryBasic principles of surgery

Halstead’s principle of not doing harm to Halstead’s principle of not doing harm to the tissuethe tissue

Set of interrelated principles: Set of interrelated principles: Tissue handling Tissue handling Tissue exposureTissue exposureHemostasisHemostasisAsepsisAsepsis

Tissue handling Tissue handling

Remember that every time you pick up Remember that every time you pick up tissue with your instruments, you kill cellstissue with your instruments, you kill cellsTry to kill as few cells as possibleTry to kill as few cells as possibleBe goal oriented in your approach Be goal oriented in your approach Sharp dissection is generally less Sharp dissection is generally less traumatic than blunt dissectiontraumatic than blunt dissection

Tissue exposureTissue exposureMake sure your view is unobstructed, with Make sure your view is unobstructed, with proper illumination and physical access proper illumination and physical access The wound should be sufficient in size and The wound should be sufficient in size and certainly not too smallcertainly not too smallDo not worry about the healing of the Do not worry about the healing of the wound, as it is not primarily affected by its wound, as it is not primarily affected by its size, but rather by appropriate size, but rather by appropriate approximation of the wound edgesapproximation of the wound edges

Let’s have a closer look at Let’s have a closer look at suture materialssuture materials

Suture size and strengthSuture size and strength

General properties of suturesGeneral properties of suturesAbsorbable, NonAbsorbable, Non--absorbableabsorbable

Always use absorbable sutures unless you have to Always use absorbable sutures unless you have to fixate somethingfixate something

BraidedBraidedTissue dragTissue dragCapillary filling effectCapillary filling effectGood handling propertiesGood handling properties

MonofilamentMonofilamentMemory effectMemory effect

PseudoPseudo--monofilamentmonofilament

AbsorbableAbsorbable

SyntheticSyntheticHydrolysisHydrolysisMinor tissue reactionMinor tissue reactionDegradation products Degradation products COCO2 2 , H, H22OO

ExamplesExamplesPolyglycolic acidPolyglycolic acidPolydioxanonPolydioxanonPolylactatePolylactate

AbsorbableAbsorbable

Tensile strength retentionTensile strength retentionVariableVariable

Polyglycolic acid (PGA)Polyglycolic acid (PGA)14 days 65% remains14 days 65% remains21 days 40% remains21 days 40% remainsGone between 56 and 70 daysGone between 56 and 70 days

PolycapronePolycaprone7 days 50% remains7 days 50% remains

14 days 25% ramains14 days 25% ramainsGone between 90 and 119 daysGone between 90 and 119 days

NonNon--absorbableabsorbable

Natural materialsNatural materialsSilk, linen and cottonSilk, linen and cotton

SyntheticSyntheticPolyesther (Dacron)Polyesther (Dacron)PolypropyleenPolypropyleenPolyamide (Nylon)Polyamide (Nylon)

MineralMineralStainless steel wireStainless steel wire

Tissue reactionTissue reaction

Qualitative ranking (Sewell et al.)Qualitative ranking (Sewell et al.)Size of the reactionSize of the reactionConcentration of cellsConcentration of cellsType of cells (phagocytes)Type of cells (phagocytes)Edema presentEdema presentNecrosis presentNecrosis presentAbsorption of the materialAbsorption of the material

Tissue reactionTissue reaction

Method acc. to Sewell et al.

0 20 40 60 80

Catgut chroom

Catgut plain

Linen

Silk

Polyamide

Mersilene

Ethibond

Vicryl

Vicryl rapide

PDS

Prolene

Stainless steel

Mat

eria

ls

Reaction rate

Reeks2Reeks1

NeedlesNeedles

ConventionalConventionalSwedgedSwedged--on atraumaticon atraumatic

Non cutting (rondNon cutting (rond--bodied)bodied)Cutting (spatula, triangle)Cutting (spatula, triangle)

NeedlesNeedles

NeedlesNeedles

Suture techniqueSuture technique

Tissue dependantTissue dependantProper instrumentsProper instrumentsProper knotting techniqueProper knotting technique

HandHandInstrumentInstrumentEqual strengthEqual strengthProper approximationProper approximation

Suture techniqueSuture technique

Suture techniqueSuture technique

Suture techniqueSuture technique

Information on the outsideInformation on the outside

Knot definition (Knot definition (TeraTera))1=1 Square1=1 Square-- or reef knotor reef knot1x1 Granny knot1x1 Granny knot2=1 Surgical knot2=1 Surgical knot2=1=1 Surgical knot with 2=1=1 Surgical knot with

extra loopextra loop

How to tie a knot?How to tie a knot?

How to tie a knot?How to tie a knot?

Cause of sutureCause of suture--related infectionrelated infectionExcessively tight suturesExcessively tight sutures

Allows bacteria to be protected in tissues made Allows bacteria to be protected in tissues made ischemic by pressureischemic by pressure

Too many sutures making large ischemic Too many sutures making large ischemic portionsportionsUse of multi filamented braided suture Use of multi filamented braided suture materials materials

Provide interstices accessible to bacteria but not Provide interstices accessible to bacteria but not to phagocytes (capillary filling)to phagocytes (capillary filling)

Cause of sutureCause of suture--related infectionrelated infectionMost pronounced in moderately Most pronounced in moderately contaminated woundscontaminated wounds

Contamination is very lowContamination is very lowThe local defenses may handle the situation despite The local defenses may handle the situation despite the presence of foreign bodythe presence of foreign bodyContamination is massive Contamination is massive ==>==> infection will occurinfection will occur

The magnitude of the wound contamination is The magnitude of the wound contamination is expressed as class I, II, III or IVexpressed as class I, II, III or IV

Suture length to wound length ratioSuture length to wound length ratio

SLWL ratioSLWL ratioHoer et al. 2001Hoer et al. 2001

Median laparotomy (ML) in ratsMedian laparotomy (ML) in ratsBest mechanical quality of healing at 4:1 Best mechanical quality of healing at 4:1 -- 8:1 ratio8:1 ratioRunning technique superior to interruptedRunning technique superior to interruptedBite size approx. 5 mm. (2Bite size approx. 5 mm. (2--3 times thickness of the wall)3 times thickness of the wall)Low suture tension ==> stronger scarsLow suture tension ==> stronger scars

Cengiz et al. 2001Cengiz et al. 2001Bite size and number of stitches in ML in ratsBite size and number of stitches in ML in rats

Best mechanical quality of healing at 4:1 ratioBest mechanical quality of healing at 4:1 ratio33--6 mm bite size6 mm bite size

Take home messagesTake home messages

Do not harm to the tissue!!Do not harm to the tissue!!Absorbable sutures are preferredAbsorbable sutures are preferredApproximation, that’s allApproximation, that’s allDo not pull sutures too tightDo not pull sutures too tightDo not tie tumbled knotsDo not tie tumbled knots

Thanks for listeningThanks for listening

Practical partPractical part

Macro knot Macro knot tyingtying (30 (30 minutesminutes))TwoTwo personspersons, , oneone roperope

TeaTea / / CoffeeCoffee breakbreakTyingTying knots knots usingusing the the anastomosisanastomosis devicedevice

33--0 0 suturessutures (60 (60 minutesminutes))55--0 0 suturessutures (60 (60 minutesminutes))

ClosingClosing remarksremarks