Abstract:

Background: The benefits of delayed wound closure for traumatic contaminated war wounds were realize and utilized frequently during World War 1, well before the discovery of antibiotics. There have been no controversies on the benefits of this technique in reducing the incidence of SSIs when applied to civilian traumatic wounds as well. However much controversy exist up to now on the benefits of this technique when applied to surgical wounds especially the surgical abdominal wall incision wound in dirty-infected intra-abdominal operations. The aim of this study was to assess the outcome benefits, if any, of delayed primary closure of the skin and subcutaneous layer of the surgical abdominal wall incision wound following dirty-infected intra-abdominal operations at Bugando Medical Centre, Mwanza, Tanzania.

Methods: This was a prospective randomized clinical study to compare the post-operative outcomes of delayed primary closure versus primary closure of the skin and subcutaneous layer in dirty-infected intra-abdominal operations over a period of 7 months from August 2014 to February 2015 inclusive at Bugando Medical Centre. After obtaining informed consent for the study patients who met the inclusive criteria were enrolled in the study. Randomization into two groups (A and B) according to the methods of the skin and subcutaneous tissue closure was done. Group A consisted of patients whose midline incisions of abdominal wall were closed primarily (primary closure group, PC) and Group B consisted of patients whose skin and subcutaneous layers were left open and closed after 3 days if no wound infection was present. (Delayed primary closure group, DPC), Patients who developed SSIs had pus swab obtained and analyzed in the laboratory for culture and sensitivity. On the third day the skin and subcutaneous tissue layers were closed for group B if no wound infection existed. Data were collected using a pre-tested coded questionnaire and analyzed by using STATA software version 11.

Results: A total of 100 patients with dirty-infected intra-abdominal surgical operations were studied. Their ages ranged from 1 years to 80 years with a mean of 30.4 years in primary closure group (PC) and 30.18 years in the delayed primary closure group (DPC). The modal age group was 10-39 years. There were 70 (70%) male patients and 30 (30%) female patients involved in this study. No surgical site infections were detected in the PC group while in the delayed primary closure SSIs were detected in 22 patients (44%). Wounds dehiscence occurred in 2% of patients in the PC group while it was 38% in the delayed primary closure group. Mean length of hospital stay was longer among delayed primary closure 11.5 days and ranged between 4-36 days compared to primary group of 7 days, ranging between 3-36 days. The most common organisms isolated in this study were Escherichia coli (22%), EnterobacteFacalis (16%) and Pseudomonas Aeruginosa (2%). All of these organisms were found to be resistant to ceftriaxone and sensitive to meropenem. The mortality rate was higher in the DPC group than in the PC group – 4 patients and 2 patients respectively.

Conclusion: The prospective comparative study at Bugando Medical Centre found that leaving the abdominal wall skin and subcutaneous layer open after dirty-infected intra-abdominal surgical operations is dangerous as it was associated with higher mortality rate, SSIs, wound dehiscence and longer hospital stay than primary closure of these layers. This is in contract to many western studies but in line with some studies done in developing countries such as India.