Additive score based on: WCC ≤ 4.5=1/WC>4.5=0 Platelets ≤ 250=1/ Platelets> 250=0 Preoperative risk score Frequency of anastomotic leak 0 1/19 (5%) 1 5/18 (28%) 2 7/11 (64%)

Table 4: Preoperative haematological score to risk stratify likelihood of anastomotic leak.