Reduction in Consequences of Contamination (Antisepsis) Sutures
The first study showing the importance of suture composition was reported in 1852 when sutures made out of silver were used for the successful repair of vesicovaginal fistulas, which had not been possible using silk (SDC-58).
In 1957, an experimental study showed that a silk suture placed in the subcutaneous tissues of humans could enhance the development of infection as much as 10,000-fold. A study 10 years later compared several types of suture material for potentiating wound infection in an experimental animal model (SDC-59). Linear polyethylene withstood contamination the best and monofilament suture materials withstood contamination considerably better than braided or twisted configurations of the same material. There was no significant difference in the incidence of infection when comparing braided waxed silk, braided nylon, or twisted surgical cotton. Those findings were supported subsequently in a canine model using a similar technique (SDC-60). A more recent study (SDC-61) examined 16 types of suture for their resistance to both Gram-positive and Gram-negative infections using a mouse model. Synthetic nonabsorbable monofilament sutures resisted infection better than multifilament sutures or catgut. Absorbable synthetic PGA type of sutures also resisted infection better than plain or chromic catgut.
The ability of sutures to enhance infection is multifactorial. Bioadherence of the bacteria to the sutures is certainly one important factor (SDC-62). Monofilament polypropylene had less adherence than braided polyester sutures with or without coating with polybutylate by a factor of up to 10 times in one study (SDC-63). Nylon bound to fewer radiolabeled bacteria than several types of braided suture by a factor of 5 to 8-fold, and the degree of infection obtained in mice in the presence of different sutures correlated well (SDC-64). Different strains of bacteria also seemed to adhere to sutures with different affinities (SDC-65). Bacteria reaching the interstices of threads in a multifilament suture are protected from phagocytosis by leukocytes, as there is no significant leukocyte penetration into the multifilament sutures (SDC-66).
Several studies have now shown that a variety of suture materials can be impregnated with antibacterial substances and antibiotics including triclosan (SDC67–70), silver (SDC-71), gentamicin (SDC-72) and neomycin (SDC-73). All of these have shown the feasibility of reducing bacterial counts in wounds. A prospective randomized clinical trial (SDC-74) demonstrated that using antimicrobial sutures compared to standard sutures could reduce the infection rate in cerebrospinal shunt surgery from 21% to 4.3%. Another recent nonrandomized observational study involving 2088 operations compared the use of a PDS loop during a baseline period with a triclosan coated polyglactin 910 suture (Vicryl plus) during a subsequent time period. The wound infection rate was 10.8% in patients with abdominal wound closure with nonantibacterial sutures compared to 4.9% with the antibacterial sutures (SDC-75).
Wound closure techniques can also make a difference in the incidence of infection. Continuous fascial closure is clearly better than using interrupted sutures (SDC-76 to 78).
Braided sutures such as silk can cause as much as a 10,000-fold decrease in the numbers of bacteria necessary to cause an infection in humans. Monofilament sutures are much less prone to potentiating infections than multifilament sutures because of decreased bioadherence of the bacteria and improvement in the ability of phagocytic cells to reach bacteria on or within the sutures. Continuous sutures of the same material are associated with fewer infections than interrupted sutures, possibly because of reduction in tissue necrosis at suture sites associated with more even distribution of tension at the suture sites and also because less suture material is left in the wound. Impregnation of the suture materials with antimicrobials may be of some benefit, but it has not been tested sufficiently in well-controlled studies.
Annals of Surgery. 2011;253(6):1082-1093. © 2011 Lippincott Williams & Wilkins
Cite this: Updated Recommendations for Control of Surgical Site Infections - Medscape - Jun 01, 2011.