Study design and setting
This is a prospective, randomized, single-blind clinical trial which was performed at the colorectal surgery division of department of surgery at Tehran University of Medical Sciences between September 1, 2016 and December 1, 2018. This study has been approved by the Research Ethics Committee of Tehran University of Medical Sciences (27th August 2016) and registered on 08/05/2017 at the Iranian Registry of Clinical Trials (www.irct.ir) with the registration number of IRCT201703158861N2. A total of 40 patients were enrolled by MM to participate in this study. Patients with a history of rectal cancer who had undergone curative low anterior resection for rectal cancer and a diverting protective loop ileostomy were enrolled in this study (n= 40). Patients with a history of immunodeficiency, complications associated with rectal anastomosis, including anastomotic leakage, para-anastomotic sinuses, and previous abdominal operation other than rectal cancer surgery, were excluded(n=0). All patients were randomly assigned into two groups using randomly permuted blocks method. random allocation sequence was generated by the online platform www.randomization.com.
First group (Group A) included patients scheduled for the hand-sewn direct repair technique and second group (Group B) for hand-sewn resection and anastomosis of the ileum. All patients were informed of the study protocol, explained the surgical techniques, their benefits, and possible complications. Written informed consent was obtained from all participants. Allocation concealment was performed using random groups (A or B) in sealed envelopes which was opened in the operation room then that specific intervention was assigned to the participant by MK. MKa, MM and MA assessed the outcome and were blinded after assignment to interventions. This trial still continues and in the second phase three groups with three interventions will be evaluated and compared.
Intervention And Surgical Techniques
In both groups, the operation was done under general anesthesia and in the supine position. Skin preparation and sterile draping were done. The skin around the ileostomy (1 to 2 millimeters from the lateral edge of the ostomy) was opened to release the ileostomy from the abdominal wall; then, the subcutaneous tissue was opened to reach the fascial surface. The intestine was then completely mobilized from the surrounding tissues and the fascia to reach the intraperitoneal cavity. Attempts were made to minimize any iatrogenic trauma to the ileum.
In group A (hand-sewn direct repair group), the edges of the antimesenteric defect on the ileum - which had been created for the ileostomy - became fresh, then sutured using 3-0 Vicryl stitches in interrupted Gambee suture patterns. Interrupted seromuscular sutures of 3-0 silk were placed to reinforce the sutures. In group B (hand-sewn resection and anastomosis of the ileum), a small section (less than 1 centimeter) of the ileum proximal and distal to the site of ostomy was resected. The two ends of the ileum were sutured using 3-0 Vicryl stitches in interrupted Gambee suture patterns. Interrupted seromuscular sutures of 3-0 silk were placed to reinforce the sutures.
In both groups, after proper hemostasis, the fascial defect was repaired utilizing separate 0 Nylon stitches. The skin was restored using 2-0 Monocryl sutures in a purse-string fashion.
Outcomes And Postoperative Follow-up
After the operation, the patients were transferred to the surgical ward. During postoperative visits, if signs of ileus, including nausea, vomiting, and abdominal distention, were not found, the oral diet was initiated. The patients were asked to try a liquid diet; if tolerated, the diet was changed to the soft, and then to the regular diet. Information about the time of gas passage, defecation, and oral feeding (including tolerance of liquid, soft and regular diet) after the operation was recorded. Potassium (K) and sodium (Na) were measured and recorded daily postoperatively. Serum potassium levels of less than 3.5 mEq/L and serum sodium levels of less than 135 mEq/L were considered as hypokalemia and hyponatremia, respectively.
After discharge, the patients were visited in the first week, first month, and then every three months up to at least six months in the colorectal surgery clinic. In follow-ups, patients were asked about possible symptoms of obstruction, including constipation, obstipation, abdominal distention, nausea, and vomiting. The physical examination was done in each visit.
Sample Size Calculation
Considering a study power of 80% and an α-level of 5%, a minimum sample size of 40 participants were calculated. The sample size was divided between the two groups of the study. Each group consisted of 20 participants.
SPSS software version 25 (IBM SPSS Statistics for Windows, IBM Corp, Chicago, IL) was utilized for statistical analysis. Student t-test was used to analyze quantitative data. P-values less than 0.05 were regarded as statistically significant. Categorical data will be shown as number and percent, and continuous data as mean and standard deviation.