Peri-anal disorders Flashcards
What are anal cushions?
The anus is lined mainly by discontinuous masses of spongy vascular tissue- the anal cushions that contribute to anal closure
The 3 anal cushions are positioned where 3 major arteries feeding the vascular plexuses enter the canal
They’re attached by smooth muscle and elastic tissue
Prone to displacement and disruption either singly or together
What are haemorrhoids/ piles?
same thing
Disrupted and dilated anal cushions
What are causes of piles?
Effects of gravity, increased anal tone, and of straining at stool make anal cushions become bulky and loose- protruding to form piles
Constipation with prolonged straining
Minor causes: Congestion from pelvic tumour, Pregnancy, Congestive cardiac failure, Portal hypertension
What is the dentate line?
Why are haemorrhoids above the line not painful?
Divides the upper two thirds and lower third of the anal canal. Developmentally represents hind-gut, proctodeum junction
There are no sensory fibres above the dentate line
Why do haemorrhoids present with PR bleeding?
Vulnerable to trauma via hard stools
Bleed readily from capillaries of underlying lamina propria, bright red blood is lost from the capillaries
Pathophysiology of piles?
Vascular cushions protrude through a tight anus
Become more congested and hypertrophy
Protrude again more readily
Protrusions may then strangulate
How do haemorrhoids present?
Bright red rectal bleeding:
Coating stools/ on tissue/ dripping into pan after defecation
Mucous discharge and pruritus ani (itchy anus)
Severe anaemia
If weight loss, tenesmus, change in bowel habit consider other pathology
Differential diagnosis of haemorrhoids ?
Anal fissure
Abscess
Peri-anal haematoma
Tumour
Diagnostic tests and results for haemorrhoids
All rectal bleeding requires:
Abdo exam,
PR exam, (Prolapsing piles are obvious, internal haemorrhoids are not palpable)
Protoscopy to see internal haemorrhoids
Sigmoidoscopy to see pathology higher up
Medical treatment for haemorrhoids?
Topical analgesics and stool softener
Increase fluid and fibre intake
Non surgical procedures for haemorrhoids?
Ribber band ligation- band produces an ulcer to anchor the mucosa. SEs: infection bleeding pain
Sclerosants: phenol injected into pile above the dentate line. SEs: impotence and prostatitis
Infrared coagulation: coagulates vessels and tethers mucosa to subcutaneous tissue
Surgical treatment of haemorrhoids?
Excisional haemorrhoidectomy
Stapled haemorrhoidopexy
Surgical complications- constipation, infection, stricture, bleeding
What are sclerosants?
Injectable irritants
What is impotence?
Man can’t get an erection or orgasm
What is an anal fistulae?
A track communicates between skin and anal canal/ rectum
Blockage of deep intramuscular gland ducts predisposes to formation of abscesses, which discharge to from fistulae
Causes of anal fistulae?
Peri-anal sepsis Abscesses Crohn's disease TB Diverticular disease Rectal carcinoma
Tests for anal fistulae?
MRI
Endo-anal ultrasound scan
Treatment
Fistulotomy + exscison
High fistulae that involves continence muscles of anus require a seton suture- tightened over time to maintain continence
Low fistulae are left open to heal naturally (secondary intention)
What is an anal fissure?
Painful tear in the squamous lining of the lower anal canal
Often, if chronic, with sentinel pile or mucosal tag at external spectrum
(females > males, 90% are posterior)
Aetiology of anal fissures?
Hard faeces
Parturition causes anterior fissures
Rare causes: Syphilis, Herpes, Trauma, Crohn’s, Anal cancer, Psoriasis
Anal spasms may constrict the inferior anal artery, what are the effects of this?
Ischaemia, makes healing difficult and perpetuates the problem
Treatment for anal fissures?
Lidocaine ointment+ GTN ointment or topical diazepam
Increase dietary fibre and fluids +- stool softener
2nd line= bo tox injection
Surgical option= lateral sphincteotomy
How does lidocaine work?
Common local anaesthetic
Uncommonly anti-arrhythmic drug
Enters cells and blocks voltage gated sodium channel
Blocks nerve fibres—> anaesthesia
In heart lidocaine increases refractory period and slows heart rate
SEs: stinging when administered, neurological effects
What is a peri- anal abscess?
Anal abscess is a painful condition in which a collection of puss develops near the anus
Usually caused by gut organisms
More common in females
Treatment for perianal abscess?
Incise and drain under anaesthetic
