1. Surgical Sutures NIHR Healthcare Technologies Co-operative in Colorectal Therapies – Foundation Miss AE Williams Clinical Research Fellow

2. Brief History 1 50,000 – 30,000 BC eyed needles were invented 20,000 BC – Renaissance bone needles were the norm Circa 1600 BC The Edwin Smith Papyrus is the first reference to sutures – ‘thou shoudst draw together for him his gash with stitching.’ Records from India 1500 BC state sutures were made from flax, hemp, bark fibre or hair

3. Brief History 2 30 AD De Re Medicina, by Aurelius Cornelius Celsus – ‘Sutures (wool or linen) should be soft, not over twisted so that they may be more easy on the part’ 150 AD Galen sutured the severed tendons of Gladiators to avoid paralysis – De Methodo Medendi ‘let ligatures be of a material that does not rot easily’ – First reference to the use of silk and catgut made from the twisted intestines of herbivorous animals

4. Brief History 3 Circa 900 AD Avicenna of Persia – traditional materials such as linen broken down rapidly in the presence of gross infection – pigs bristles (the first monofilament suture) Suture technology didn’t really progress until John Hunter’s Era – Late 1700s experimentation with various materials in order to find the best absorbable suture tendon, varnished leather, buckskin etc 1800s major surgical advances of anaesthesia use and antiseptic techniques were adopted Lister developed the first antibacterial suture by soaking fine catgut in a solution of carbolic acid 1900s the catgut industry was established in Germany and iodine sterilisation was developed

5. Brief History 4 The outbreak of WW1 lead to British manufactures having to come up with their own suture materials – The manufacturer George Merson of Edinburgh developed eyeless needles 1960 Cobalt 60 isotopes were developed to allow sterilisation by radiation – sutures could be produced, packaged and then sterilised G.F.Merson became Ethicon Ltd and in the 1970’s – producing catgut from the intestines of 26,000 sheep per day 20 th Century developments have meant catgut has been phased out and has been replaced by synthetic materials (absorbable and non absorbable) – polyester, nylon, polypropylene, polydioxanone and polyglycolic acid

6. The Ideal Suture Use for any Procedure Easy to Handle Minimal tissue reaction High tensile strength Holds knot securely Predictable absorption rate Sterile and low risk of infection

7. Which Suture? Need the right one for the job – Take into consideration Requirement for length of wound support – Needs to retain its strength for the desired time Difference in healing rates of tissues and organs Patient factors – Infection, disability, nutritional state etc Surgeon’s individual preference – familiarity, ease of handling and knot tying, etc

8. Suture Types Biologic vs synthetic Absorbable vs non absorbable Braided vs Monofilament Dyed vs undyed Fine vs big ‘proper’ suture Modified and coated

9. Biologic vs Synthetic Biologic – Silk (and catgut) – Non absorbable, loses strength over time – Uses: drain sutures Synthetic – ALL THE REST – Can be non absorbable and absorbable – Uses: wound closure, anastomoses, tendon repair etc

10. Absorbable vs Non-Absorbable E.g. silk, ethibond and steal wire is non absorbable E.g. PDS, vicryl and monocyrl are absorbable Refers to the bodies ability to naturally degrade the material in the suture or not Various processes for absorption – E.g.hydrolysis, proteclytic enzyme degradtion, etc Rate of absorption depends on material but ranges from 1 – 3 months Both can be used internally and externally Non-Absorbable are walled off and encapsulated by fibroblasts as they act as a ‘foreign body’ – Hence need for removal if used in skin closure

11. Braided vs Monofilament Monofilament – E.g Prolene – Single strand – Resist the harbouring of bacteria Smooth surface – Glide through tissues Less trauma – Tie down smoothly – Can have ‘memory’ Braided – E.g. Vicryl, Ethibond – Several strands twisted or braided – Grips the tissue to hold it together – Good handling – Good Knot tying – ?Higher infection rate

12. Dyed vs Undyed It not just about making it look colourful Helps with visibility especially if covered in blood Denotes suture type and anatomical structures Important in cosmesis and avoidance of tattooing

13. Size Again right size for the job Fine sutures for fine work Modern sutures range from a 5 (the thickest diameter) – 11’0 (the thinnest diameter) The more 0’s the smaller it is and the less tensil strength

14. Modified and Coated Modified – Barbed Monofilaments No knot tying required – Laparoscopic sutures V-Loc device again no tying required Coated Sutures – Triclosan Coated Sutures Bacteriostatic agent that inhibits fatty acid synthesis Certain small studies have shown a reduction in Surgical Site Infections Systematic Review from 2012 said they don’t …. – Stem Cell Coated Sutures ASCs covered/cultured in sutures to aid wound healing

15. Questions