A systematic review of the literature assessing operative blood loss and postoperative outcomes after colorectal surgery.

Purpose: There is no consensus in the literature regarding the association between operative blood loss and postoperative outcomes in colorectal surgery, despite evidence suggesting a link. Therefore, this systematic review assesses the association between operative blood loss, perioperative and long-term outcomes after colorectal surgery.

Methods: A literature search of MEDLINE, EMBASE, Science Citation Index Expanded and Cochrane was performed to identify studies reporting on operative blood loss in colorectal surgery.

Results: The review included forty-nine studies reporting on 61,312 participants, with a mean age ranging from 53.4 to 78.1 years. The included studies demonstrated that major operative blood loss was found to be a risk factor for mortality, anastomotic leak, presacral abscess, and postoperative ileus, leading to an increased duration of hospital stay. In the long term, the studies suggest that significant blood loss was an independent risk factor for future small bowel obstruction due to colorectal cancer recurrence and adhesions. Studies found that survival was significantly reduced, whilst the risk of colorectal cancer recurrence was increased. Reoperation and cancer-specific survival were not associated with major blood loss.

Conclusion: The results of this systematic review suggest that major operative blood loss increases the risk of perioperative adverse events and has short and long-term repercussions on postoperative outcomes. Laparoscopic and robotic surgery, vessel ligation technology and anaesthetic considerations are essential for reducing blood loss and improving outcomes. This review highlights the need for further high quality, prospective, multicentre trials with a greater number of participants, and accurate and standardised methods of measuring operative blood loss.