OBJECTIVELaparoscopic colorectal surgery is a skill-dependent procedure. The present study aims to analyze the learning curve of a properly trained surgeon, with basic laparoscopic techniques, to become skillful in performing laparoscopic colorectal operations.

METHODSA series of non-selective, consecutive 189 cases of laparoscopic colorectal surgery were accomplished, from December 2009 to February 2012, by one surgeon with years of skilled technique in laparoscopic cholecystectomy, rich experience in assisting laparoscopic colorectal surgery, and experience of approximately 180 procedures of gastric and colorectal surgery annually. 170 out of 189 procedures were radical operations for colorectal neoplasma, including right colectomies in 28 cases, left colectomies in 5 cases, sigmoidectomies in 28 cases, high Dixon procedures in 45 cases, low Dixon (total mesorectal excision, TME) procedures in 41 cases and Miles procedure in 23 cases. 19 other patients underwent combined procedures for multi-primary tumors or inflammatory enteritis. All these procedures were analyzed according to time span (the earlier half and later half) in respect to length of surgery, intraoperative blood loss, number of lymph nodes retrieved, intraoperative events and postoperative complications.

RESULTSFor radical right colectomy, the D2 dissection conducted in the earlier phase (n = 8) had the similar length of surgery, more blood loss and less LN retrieval, compared with the D3 dissection conducted in recent phase (n = 20). The earlier performed high Dixon procedures (n = 22) consumed longer time than the later procedures (n = 23) consumed, but with similar blood loss and LN retrieval. Low Dixon (TME) procedures showed significant differences in length of surgery and blood loss relative to time span. Recently performed simoidectomy and Miles procedures showed a trend of shorter time consumed compared with earlier performed procedures. Conversion ratio to open surgery was 1.05%. Adverse effects occurred in 8 cases of surgeries, including intestinal injury (3/189), insufficient distal margin (2/189), intraoperative bleeding (2/189) and vaginal injury (1/76). There was no operative death. Chief complications included urinary retention 5.82%, ileus 4.76%, anastomotic leak 4.24%, perineal infection 23.08% (6/26), wound dehiscence 2.65%, gastrointestinal bleeding 1.59%, peritoneal infection 1.06%. Surgery for distal rectum tended to have more complications, such as urinary retention, anastomotic leak and perineal infection. The later performed low Dixon procedures produced insignificantly fewer anastomotic leaks than those in the earlier phase.

CONCLUSIONSFor a trained surgeon with basic laparoscopic techniques, there are at least 15 - 25 cases of different procedures needed for him/her to become skilled to perform laparoscopic surgery. The learning curve should also depend on the annual number of colorectal surgeries.