Conversion in mini-invasive colorectal surgery: the effect of timing on short term outcome

Different results have been reported about postoperative outcomes of conversion during laparoscopic colorectal surgery. We aimed to detect the effect of conversion on postoperative outcome and to identify features associated to better outcome after conversion.

Two hundred-fourteen mini-invasive left colonic and rectal resections were retrospectively analysed. Two groups were identified: mini-invasive colorectal surgery (MI) that includes both laparoscopic and robotic resections, and conversion to open surgery.

Among 214 colorectal procedures, 189 were MI. Conversion rate was 11.7%. Operating time was shorter for MI at overall analysis (p 0.003) and sub-analysis of left colectomies (p 0.001). MI procedures had shorter hospital stay (p 0.000) both in left colectomy and rectal resection (p 0.008 and p 0.001 respectively). A shorter time to first flatus emission was detected in MI group in both overall analysis (p 0.003) and procedure's sub-analysis (left colectomy p 0.032; anterior rectal resection p 0.040). Oral feeding was resumed earlier after mini-invasive rectal resections (p 0.014). Converted procedures required more blood transfusions (p 0.000) and grade II complication rate was lower after MI procedures (p 0.013). Conversion presented higher anastomotic leakage and reoperation rates (p 0.035 and p 0.006 respectively). Conversion before 105 min (early conversion) had a significant lower number of blood transfusions (p 0.047).

Conversion is associated to higher rate of blood transfusions, grade II complication and slower recovery. Earlier conversion has better outcomes. Colorectal surgeons should identify any critical aspects that could avoid late conversion allowing reducing negative effects of conversion.