Inclusion Criteria:

- colorectal cancer

- diverticulitis

- colonic volvulus

- colorectal polyp

Exclusion Criteria:

- Age < 18 years

- Inability to give informed consent

- Emergency surgery

- Pregnancy

- Comorbidity resulting in altered abdominal circumference measurement:

ascites secondary to chronic liver disease peritoneal carcinomatosis intestinal
obstruction abdominal mass lesions >20cm diameter on CT scan. pre-existing abdominal stoma
incisional hernia

- Inflammatory bowel disease: it is recognised that this group of patients carries a
well-recognised increased risk of a number of adverse outcomes (e.g. venous
thrombo-embolism) and elevated inflammatory parameters therefore it is proposed to
exclude this group from the study.