INTRODUCTION:
The infection of a wound can be defined as the invasion of organisms through tissues following a breakdown of local and systemic host defences, leading to cellulitis, lymphangitis, abscess and bacteraemia. Infections of surgical wounds are called as surgical site infections (SSIs).
SSIs are defined as infections occurring within 30 days after a surgery or within one year if an implant is left in place after the procedure and affecting either the incision or deep tissue at the operation site.
According to the National Nosocomial Infection Surveillance program (NNIS), it is classified into superficial, deep, organ/space infections.
Source of SSIs include the patient‘s own normal flora, organisms present in the hospital environment that are introduced into the patient by medical procedures, specific underlying disease, trauma or burns which may cause a mucosal or skin surface interruption.
SSIs are serious operative complications that occur in approximately 2% of surgical procedures and account for 20% of health care-associated infections. Many studies reported that SSIs rank third among common nosocomial infection next only tourinary tract and respiratory tract infections.
Recent studies reported that SSI rate ranges from 19.4% to 36.5% 7all over the world, whereas in India it ranges from 3% to 12%. SSI remains a common and widespread problem that contributes to significant morbidity and mortality, prolongs hospital stay and consequently increasing health care cost.
AIMS AND OBJECTIVES:
1. To find out the prevalence of SSI in this hospital.
2. To elicit the association between bacterial isolates and anatomical site of infection.
3. To identify the probable risk factors for development of surgical site infections.
4. To isolate and identify aerobic pathogenic bacteria from surgical site infections (SSI).
5. To determine the antimicrobial sensitivity pattern of pathogens.
MATERIALS AND METHODS:
This was a Hospital based Prospective Cross sectional study and carried out at the Department of Microbiology, Trichy SRM Medical College Hospital and Research Centre, Irungalur, Trichy, Tamilnadu. The study was carried out over a period of one year (May 2017 to April 2018).
MATERIALS:
Consecutive cases of both sexes and all adults belonging to various surgical wards and underwent surgical procedure during the study period comprising of elective as well as emergency were considered for the present study.
Patients belonging to anyone of the following were excluded.
1. Paediatric cases.
2. Cases taken for second surgery at the same site for any reason.
3. Patients on immunosuppressant or with immunodeficiency status.
4. Patients on antibiotics already for any other infections.
5. Presence of infection elsewhere in the body or focal sepsis.
RESULTS:
The study, “Bacteriological Profile, Antibiogram and Risk Factors of Surgical Site Infections in a Tertiary Care Hospital” was carried out in the Department of Microbiology, Trichy SRM Medical college Hospital and research centre, Trichy and the results were analyzed for the Surgical site infections (SSIs) rate as per class of wound, type of surgery, antibiotic prophylaxis, risk factors, drug
resistance and American society of anesthesiologist index.
Prevalence of SSIs:
A total of 2076 patientsunderwent different types of surgeries comprising of elective as well as emergency during a 12-month period (May 2017 – April 2018).
The types of surgeries done in this hospital during the study period are listed in the table no.10. During the 12 consecutive months of study period, 116 surgical site
infections were documented and hence,the overall prevalence of surgical site infection rate during the study period was 5.6%(n=116). Among the 2076 surgeries, abdominal surgeries constituted (n =739 ; 35.6%) the highest rate of SSI occurred in the category of exploratory laparotomy. 78 underwent exploratory laparotomy, 20 developed SSIs
(25.6%).
CONCLUSION:
A total of 2076 patients underwent various surgeries including elective as well as emergency surgeries during consecutive 12 months commencing from May 2017 – April 2018. Standard methods were adopted to collect sociodemographic, clinical and microbiological data. SSIs were suspected in 134 patients. The clinical signs and symptoms started appearing from 4th day onwards and more no of cases manifested features of infection either on 5th or 6th
postoperative day. 18 samples showed no growth and the remaining 116 samples yielded 124 isolates (8 were polymicrobial infections).
The prevalence rate of SSI in our hospital during the study period was 5.6%.The SSI were more common in abdominal surgeries highest being in laparotomy surgeries (20/78; 25.6%). The odd‘s ratio for the development of SSIs in emergency cases was 0.57 and among males was 1.61. All these cases had one or other risk factors also.
The occurrence of SSIs was high in dirty (41.2%) and contaminated surgical wounds (11.2%) when compared to clean surgeries. Interestingly, SSIs were more among those belonging to age group 16-24 yrs (11.9%) and odd‘s ratio was 2.45. SSI was independent of prophylactic antibiotic administration. During the study period, SSIs developed in all patients who received prophylactic antibiotics thereby indicating that prophylactic antibiotics did not protect the individual from developing SSIs.
Smear studies of 134 samples revealed pus cells in all but smear had bacterial agents in only 37. For practical purposes, SSIs have to be considere