Rectum/anal conditions Flashcards
What are haemorrhoids?
Disrupted and dilated anal cushions
The anus is lined by discontinuous masses of spongy vascular tissue – the anal cushions which contribute to anal closure.
These become enlarged and engorged with a tendency to protrude, bleed or prolapse in the anal canal
How can haemorrhoids be classified?
Internal
- Arise from the superior haemorrhoidal plexus
- Lie ABOVE the dentate line
External
- Lie BELOW the dentate line
NOTE: dentate line = a line that divides the upper 2/3 and the lower 1/3 of the anal canal and represents the hindgut-proctodeum junction
How are haemorrhoids graded?
- 1st Degree - haemorrhoids that do NOT prolapse
- 2nd Degree - prolapse with defecation but reduce spontaneously
- 3rd Degree - prolapse and require manual reduction
- 4th Degree - prolapse that CANNOT be reduced
Expain the aetiology of haemorrhoids
Caused by disorganisation of the fibromuscular stroma of the anal cushion
Become enlarged and engorged with a tendency to protrude, bleed or prolapse in the anal canal
State some risk factors for haemorrhoids
The 3 anal cushions are attached by smooth muscle and elastic tissue, but are prone to displacement and disruption, either singly or together due to:
- Constipation
- Prolonged straining
- Derangement of the internal anal sphincter
- Pregnancy
- Portal hypertension
Summarise the epidemiology of haemorrhoids
COMMON
Peak age: 45-65 yrs
What are the presenting symptoms of haemorrhoids?
Painless rectal bleeding
- bright bleeding in association with defecation or straining at stool.
Perianal pain
- Severe in thrombosed external haemorrhoids
- May be associated with feeling of incomplete evacuation.
Tender palpable perianal mass
- when there is acute thrombosis
ABSENCE of alarm symptoms (weight loss, anaemia, change in bowel habit, passage of clotted or dark blood, mucus mixed with the stool)
How do you recognise haemorrhoids on physical examination?
1st or 2nd degree haemorrhoids are NOT usually visible on external inspection or palpable on DRE unless they are thrombosed
Haemorrhoids are usually visible on proctoscopy- anoscopic examination
colonoscopy/flexible sigmoidoscopy- exclude serious pathology
Ddx for haemorrhoids
- Anal tags
- Anal fissures
- Rectal prolapse
- Polyps
- Tumours
Generate a management plan for haemorrhoids
The main aim of treatment is relief of symptoms.
-
grade 1 haemorrhoids
- topical corticosteroids
- diet + lifestyle modifications- high fibre, increased fluid intake
-
grade 2/3 prolapsing internal haemorrhoids
- rubber band ligation
- sclerotherapy
-
grade 4 internal, external, or mixed internal and external haemorrhoids
- Milligan-Morgan haemorrhoidectomy - excision of three haemorrhoidal cushions
- involves excision of piles +/- litigation of vascular pedicles, as day-case surgery
Identify possible complications of haemorrhoids
- anaemia from continuous/excessive bleeding
- thrombosis- sudden onset of perianal pain and the appearance of a tender nodule adjacent to the anal canal.
- incarceration- of prolapsing haemorrhoidal tissue
following surgical haemorrhoidectomy:
- faecal incontinence
- pelvic sepsis
- anal prolapse/stenosis
Summarise the prognosis for patients with haemorrhoids
- Often CHRONIC
- High rate of recurrence
- Surgery can provide long-term relief
Define anal fissure
Split in the skin of the distal anal canal characterised by pain on defecation and rectal bleeding.
NOTE: 90% of anal fissures are posterior (anterior anal fissures tend to occur after childbirth)
Summarise the epidemiology of anal fissures
- Affects 1/10 people during their life time
- Both sexes are affected equally
- Second commonest gastro-intestinal complication of pregnancy after haemorrhoids.
- Most cases occur 15-40 yrs
What are the risk factors of anal fissure?
- Idiopathic
- Passage of hard stool- hard stool tears the anal skin from the pectin (at the dentate line)
- Opiate analgesia- associated with constipation
- When a hard stool that tears the anal skin is passed, there is not sufficient blood supply to heal the split in the skin because:
- poor circulation in the posterior midline of the anal canal
- anal sphincter spasm → constrict inferior rectal artery → ischaemia