A randomized pilot study on single-port versus conventional laparoscopic rectal surgery: effects on postoperative pain and the stress response to surgery.

Abstract

Potential benefits of single-port laparoscopic surgery may include improved cosmetic results, less postoperative pain, surgical trauma and faster recovery. Results of randomized prospective studies with a focus on single-port rectal surgery have not yet been presented. The aim of the present study was to compare single-port and conventional laparoscopic surgery for rectal cancer in terms of short-term outcomes including postoperative pain and trauma-induced changes in certain bioactive substances. Patients with non-metastasized rectal cancer were prospectively randomized to single-port (n = 20) or conventional laparoscopic rectal surgery (n = 20). Postoperative pain was assessed at rest, at coughing and during mobilization, with a numeric pain ranking score and was recorded at 6 h after the operation and subsequently every morning daily for 4 days. Levels of C-reactive protein (CRP), interleukin-6 (IL-6) and tissue inhibitor of metalloproteinases-1 (TIMP-1) were determined. Blood samples were collected preoperatively (baseline), and 6, 24, 48, 72 and 96 h after skin incision. Pain scores were significantly reduced in the single-port group on postoperative days 2, 3 and 4 during coughing and mobilization. In addition, the patients in the single-port group suffered significantly less pain at rest at 6 h after surgery and on postoperative days 1, 3 and 4. The levels of the three markers increased significantly after surgery. The increase was similar between groups for plasma IL-6 and TIMP-1 at all time points, while the CRP levels were significantly lower in the single-port group at 6 (p < 0.001) and 24 h (p < 0.05) after skin incision. Abdominal incisions lengths were significantly shorter in the single-port group (p = 0.001). There was no significant difference between groups in operating time and blood loss, morbidity or mortality rate. The short-term oncological outcome in the two groups was similar. Single-port rectal surgery may reduce postoperative pain. Although CRP levels were lower at some time points, results of the present randomized, pilot study suggest that the trauma-induced inflammatory response of single-port operations may be similar to the trauma-induced inflammatory response of conventional laparoscopic surgery.