Clinico-Surgical Factors Affecting Surgical Site Infection in Colorectal Surgical Procedures

Introduction: Surgical site infections (SSIs) are the third most common nosocomial infections, accounting for 38% of nosocomial infections among surgical patients. SSIs after colorectal surgical procedures are associated with increased morbidity, mortality, hospital stay and cost of treatment. The various risk factors for the development of SSI depend upon the patient characteristics as well as the surgical procedure.

Aims and objectives: To study the incidence of SSI and various clinico-surgical factors affecting the occurrence of SSI in patients undergoing colorectal surgery. 

Material and methods: This 2 year prospective study included total of 350 patients who underwent different types of colorectal surgical procedures depending on the underlying pathology. Parameters studied were age, sex, BMI, nutritional status, smoking history, ASA grade, associated co-morbidities, type of surgical approach (open or laparoscopic) and mean operating time. Postoperatively patients were followed for development of any SSI and data as such collected was subjected to various statistical analysis tests and preoperative risk factors were correlated with postoperative SSI taking into consideration the statistically significant results only where p-value was <0.05.

Results: Total of 350 patients were included in this hospital based prospective study from June 2013 to May 2015. The overall incidence of SSI in our study was 17.4%.  Rate of SSI in patients with some associated co-morbidity was 21.5% while as it is about 14.1% in the patients without any comorbidity. However we did not find any statistically significant correlation of SSI with smoking status, surgical settings (elective vs emergency) and surgical approach (open vs laparoscopic). SSI rate in patients with BMI>25 was 29.2% while it was 11.3% in patients with BMI<25 (p-value of 0.01). SSI developed in 14.1% patients with ASA grade-I and 21.9% patients with ASA grade-II and none in ASA grade-III. With respect to age group the incidence of SSI in our study was highest in age group 75-95 (66.7%) and lowest in youngest age group 15-35 (10.6%); (p-value of 0.001). Also mean operating time was higher in patients that developed SSI (179.54±37.21) as compared to those that didn’t develop SSI (156.33±49.58); (p value=0.012). Incidence of SSI in our study was 5.9% in well built patients and 33.3% in under-nourished patients (p-value 0.0001).

Conclusion: Overall incidence of SSI in our study (17.4%) is comparable to that reported in literature. The incidence of SSI is significantly higher in patients with higher BMI (obese patients), with higher mean operating time, higher age-group patients and in under-nourished patients.