Colorectal surgery Flashcards
Most common anal cancer
SSC
Borders of anal canal
Anorectal junction
Anal margin
Where do anal margin tumours spread
inguinal lymph nodes
Where to more proximal anal tumours spread
Pelvic lymph nodes
RF for anal cancer
HPV
Anal intercourse
MM sex
HIV
Presentation of anal cancer
Perianal pain
Perianal bleeding
A palpable lesion
Faecal incontinence
Presentation of anal fissure
painful, bright red, rectal bleeding
Where do 90% of anal fissures occur
Posterior midline
Alternative location ? consider underlying cause (e.g. crohns)
RF for anal fissures
- constipation
- inflammatory bowel disease
- sexually transmitted infections e.g. HIV, syphilis, herpes
Acute fissure management (<1wk)
- Dietary advice: high-fibre diet with high fluid intake
- Bulk-forming laxatives are first-line - if not tolerated then lactulose should be tried
- Lubricants such as petroleum jelly may be tried before defecation
- Topical anaesthetics
- Analgesia
Chronic fissure management
topical glyceryl trinitrate (GTN) is first-line treatment for a chronic anal fissure
How are haemorrhoids classified ?
- 1st degree: no prolapse
- 2nd degree: prolapse when straining and return on relaxing
- 3rd degree: prolapse when straining, do not return on relaxing, but can be pushed back
- 4th degree: prolapsed permanently
Common presentation of haemorrhoids
-> Painless, bright red bleeding. Typically on the toilet tissue.
-> Sore / itchy
-> Feeling a lump around or inside the anus
Treatment for haemorrhoids
- Increase fibre and fluids
- Topical : anusol
- Non surgical : rubber band ligation, injection sclerotherapy
- Surgical : haemorrhoidal artery ligation, haemorrhoidectoimy
How can haemorrhoids be prevented
- Increasing the amount of fibre in the diet
- Maintaining a good fluid intake
- Using laxatives where required
- Consciously avoiding straining when opening their bowels
Screening for colorectal cancer
- Faecal immunochemical test testing every 2 yrs for anyone aged 60-74
- Detects and quantifies amount of human blood in single stool sample
Presentation of colorectal cancer
- Rectal bleeding
- Chnage in bowel habit
- Abdo pain and discomfort
- Unexplained weight loss
- Anaemia
- Bowel obstruction
tumour marker for colorectal cancer
Carcinoembryonic antigen
Colorectal cancer of caecal, ascending or proximal transverse colon
Right hemicolectomy with ileo-colic anastomosos
cancer of Distal transverse, descending colon
Left hemicolectomy with Colo-colon anastomosis
Cancer of sigmoid colon
High anterior resection with colo-rectal anastomosis
Cancer of upper rectum
Anterior resection with colo-rectal anastomosis
Cancer of low rectum
Anterior resection with colo-rectal anastomosis (+/- defunctionin stoma)
RF for colon cancer
- FHx
- Familial adenomatous polyposis (AD)
- Hereditary nonpolyposis colorectal cancer (AD)
- IBD
- Obesity
- Smoking
- Alcohol
What is diverticular disease
herniation of colonic mucosa through muscular wall of colon
Risk factors for diverticulosis
- Increased age
- Low fibre diet
- Obesity
- Use of NSAIDs
Presentation of diverticulosis
- Lower left abdominal pain
- Constipation
- Rectal bleeding
Management of diverticulosis
- Increased fibre diet
- Bulk forming laxatives
Presentation of acute diverticulitis (7)
- Pain and tenderness in the left iliac fossa / lower left abdomen
- Fever
- Diarrhoea
- Nausea and vomiting
- Rectal bleeding
- Palpable abdominal mass (if an abscess has formed)
- Raised inflammatory markers (e.g., CRP) and white blood cells
Management of uncomplicated acute diverticulitis in primary care (4)
- Oral co-amoxiclav (at least 5 days)
- Analgesia (avoiding NSAIDs and opiates, if possible)
- Only taking clear liquids (avoiding solid food) until symptoms improve (usually 2-3 days)
- Follow-up within 2 days to review symptoms
Complications of diverticulitis
- Perforation
- Peritonitis
- Peridiverticular abscess
- Large haemorrhage requiring blood transfusions
- Fistula (e.g., between the colon and the bladder or vagina)
- Ileus / obstruction
Explain Duke’s classification for colorectal cancer
A : confined to mucosa
B : invades bowel wall
C : lymph node mets
D : distant mets
Define ischaemic colitis
transient comprimise of blood flow to large bowel
define acute mesenteric ischaemia
Embolism occluding artery suplying small bowel (e.g. superior mesenteric)
Presentatio of acute mesenteric ischaemia
often AF Hx
Abdo pain severe, sudden and out of keeping with physical exam findings
Mx of acute mesenteric ischaemia
Immediate laparotomy
3 causes of large bowel obstruction
- tumour
- volvulus
- Diverticular diease
Large bowel obstruction present ?
- Absence of passing flatus or stool
- Abdominal pain
- Abdominal distention
- Nausea and vomiting are late symptoms that may suggest a more proximal lesion
Diagnosis and key finding of bowel obstruction
- X ray = distended loops of bowel
what will be seen on bloods in bowel obstruction and why ?
- Electrolyte imbalances
- Metabolic alkalosis due to vomiting (VBG)
- Raised lactate (bowel ischaemia)
Initial management of bowel obstruction
” Drip and suck “
- Nil by mouth (don’t put food or fluids in if there is a blockage)
- IV fluids to hydrate the patient and correct electrolyte imbalances
- NG tube with free drainage to allow stomach contents to freely drain and reduce the risk of vomiting and aspiration
RF for volvulous
Neuropsychiatric disorders (e.g., Parkinson’s)
Nursing home residents
Chronic constipation
High fibre diet
Pregnancy
Adhesions
Investigation of choice for volvulus
Contrast CT
Finding on abdominal x-ray in sigmoid volvulus
” Coffee bean “
Features of perianal abscess
- Pain around the anus, which may be worse on sitting;
- Hardened tissue in the anal region;
- There may be pus-like discharge from the anus;
- If the abscess is longstanding, the patient may have features of systemic infection.
Tx of perianal abscess
- Incision and drainage
What operation is done for colorectal cancer if they present with perforation
Hartmann’s -> resection of sigmpid colon and end colostomy fashioned
Most common histiological subtype of colorectal cancer
Adenocarcinoma
Surgery for anal verge cancer (tumour of low rectum with a projection inferior to within 1cm of dentate line)
abdomino-perineal excision of rectum
Location, appearance and ouput of ileostomy
- RIF
- Spouted
- Liquid contents
Location, appearance and output of colostomy
- Varies, often left side
- Flush with skin
- Solid
why are small bowel stomas often spouted and colonic ones are not ?
- Small bowel is spouted as the content is more irritant and so does not want to be in contact with skin
- Colonic content is more alkaline and so can be flush with skin
