Efficacy of Topical Gentamicin with single dose IV Ceftriaxone versus single dose IV Ceftriaxone in the prevention of Surgical Site Infection after open prosthetic inguinal hernia repair; A 1-year Randomized control trial.

A hernia is defined as the abnormal protrusion of a viscus or a part of it through a weak point in the body. Inguinal hernia occurs either through the deep inguinal ring (indirect hernia) or through the posterior wall of the inguinal canal (direct hernia). Due to its low recurrence rates and convenience of use, the Lichtenstein tension-free inguinal hernia repair using polypropylene mesh is the preferred method; as a result, the usage of prosthetic mesh for inguinal repair has significantly expanded .

 Surgical site infections (SSI) are infections present in any location along the surgical tract after a surgical procedure. By definition, they can occur anytime from 0 to 30 days after the operation or upto 1 year after a procedure that has involved the implantation of a foreign material. It involves postoperative infections occurring at any level (incisional or deep) of a specific procedure. They are divided into a) Incisional superficial (skin, subcutaneous) b) Incisional deep (fascial plane and muscles) c) Organ/ space related (anatomical procedure of the procedure itself) .

 SSI is the most frequent complication in inguinal hernioplasty. It is a bothersome complication for both surgeons and patients since it wastes time and money and accounts for 20% of all healthcare-associated infections. General hospitals, especially centers who receive every kind of surgical case, including trauma and contaminated cases, may have SSI rates >5%. Although inguinal hernia repair is a clean surgical treatment with an average surgical site infection rate of less than 2% in hernia center hospitals, each institution has its own infection rate, and many of them are unable to achieve such a low rate .

When repairing an inguinal hernia, first- or second-generation cephalosporins are typically administered intravenously prior to skin incision as antimicrobial prophylaxis . While this prophylactic can reduce the SSI rate, in many locations the SSI rate still exceeds 2% even with intravenous antibiotic prophylaxis. Topical antibiotics have been employed for the treatment of infected wounds. Commonly used antibiotics for topical prophylaxis are cephalosporins, aminoglycosides, glycopeptides, chloramphenicol and bacitracin.

 Gentamycin is an amino-sugar linked by a glycosidic bond to a central aminocyclitol ring . It inhibits the growth of bacteria in a concentration-dependent manner, regardless of the size of the inoculum, by first diffusing passively through the outer membrane of the bacterial pores and then crossing the membrane by an energy-dependent mechanism. It attaches to the 30 ribosomal subunit after it enters the cytoplasm, causing incorrect mRNA codon reading and the incorrect amino acids to be integrated into bacterial proteins. The killing effect of gentamycin is concentration-dependent and is followed by a bacteriostatic effect.It is primarily efficient against Gram-negative bacteria, although it also has the ability to kill staphylococci, which includes S. aureus and S. epidermidis. At the concentration used, it would be bactericidal and not bacteriostatic and it shows antimicrobial synergy when used in combination with B-Lactams.

 Applying topical antibiotics enables the use of a concentration that is significantly higher than systemic injection. Thus, resistance to antibiotics brought on by low drug dosage is prevented. The blood concentration of antibiotics stays low, lowering ototoxicity and nephrotoxicity, while the local drug concentrations are maintained for at least 48 hours. It is able to improve collagen type I/III ratio, scar ratio and mesh integration, thus help in faster wound healing and fibrin formation.

 Even though inguinal hernia surgery is a clean surgery, the surgical site infection is around 5-8% in a tertiary care centre, and this study might potentially help to reduce the SSI < 2% and thus helps achieving the perfect surgical outcome in a effective and feasible manner and thus leading to an excellent patient care and also the inconvenience caused by the SSI by using topical gentamicin.