Synopsis
Assess rectal bleeding by combining physiological severity, bleeding pattern, anorectal examination and current cancer-pathway criteria, while avoiding false reassurance from a benign lesion or a single laboratory value.
- Resuscitate before localisation when rectal bleeding causes shock or continuing circulatory compromise.
- Describe whether blood coats or mixes with stool, its volume, pain, recurrence and associated mucus.
- Weight loss, bowel-habit change, abdominal pain, iron deficiency or a mass require colorectal cancer assessment.
Key red flags
Large-volume or continuing bleeding with syncope, tachycardia, hypotension, pallor or reduced urine output requires immediate resuscitation and urgent senior assessment.
Investigation priorities
quantify immediate physiological impact and obtain a baseline haemoglobin and platelet count
Management branches
A 58-year-old has six weeks of painless blood mixed with looser stool. Examination finds small non-bleeding haemorrhoids but no rectal mass; haemoglobin is 111 g/L and quantitative FIT is 28 micrograms haemoglobin per gram.
- Confirm stable observations and no current heavy bleeding, then quantify the duration, blood-stool relationship, weight change, family history, medicines and previous colorectal investigation.
- Record the non-bleeding haemorrhoids without treating them as the complete explanation; a normal low-rectal examination cannot assess the proximal rectum or colon.
A 31-year-old has sharp pain during defaecation and a small streak of blood on paper; inspection shows a posterior fissure, with no bowel-habit change, weight loss, anaemia or mass.