Colorectal surgery Flashcards
IBD
Crohn’s
Inflammatory disease which can occur anywhere in GI tract (mouth-anus), but esp. terminal ileum
Sx: diarrhoea (bloody/nonbloody), abdo pain, weight loss
Signs: perianal lesions - fistulae, absccess, clubbing
Risk fx: smokers, 20-40yrs
Complications: toxic dilatation (less common than in UC), SBO, abscess, fistula
Ix: FCB (anaemia), Bloods (CRP), B12/folate/iron, faecal-calprotectin (GI inflammation), stool culture (E. coli, C. diff)
Colonscopy
Histology: transmural (all layers), skip lesions, granulomas, fistula, ulcers
Tx:
mild: budesonide (oral)
mod: anti TNF (infliximab) + oral corticosteroid taper
severe: hospitilisation + IV pred
surgery if: abdo mass, signs of intestinal obstruction
Maintenance: Azathioprine or methotrexate
(if steroids >2/yr)
UC
Inflammatory disease of colonic mucosa, affects rectum (proctitis) to entire colon (pancolotis) - (esp rectum, sigmoid) ((sigmoid involved in most diseases of colon - colitis, volvulus, carcinoma, polyposis, diverticulitis))
Risk fx: young adults, elderly, enteric infection e.g. salmonella
smoking reduces risk
Sx: relapsing/remitting, bloody diarrhoea, cramping abdo pain, tenesmus fever, weight loss
Signs: erythema nodosum (painful, esp on shins), pyoderma gangrenosum , PSC, arthritis
Ix: FBC, CRP, Stool culture (E. coli, C.diff), LFTs (PSC - increase Alk phos) Abdo XR (toxic diliatation >6cm)
Flex Sigmoidoscopy (if acute)
Colonoscopy
Barium enema - drainpipe colon (smooth walled, cylinder shaped)
Microscopy: mucosal, psuedopolyps
Assessing severity: no. bowel motions, rectal bleeding, temp, Hb, HR, CRP
Complications: toxic dilatation (leading to perf), colon Ca., venous thromboembolism (needs prophylaxis)
Tx:
Mild (distal): PR mesalazine , extensive: oral mesalazine
SE: monitor FBC, UEs (renal impairement)
2nd line: PR hydrocortisone or oral mesalazine
Mod: oral + PR mesalazine + oral steroids
Severe (>6 motions): hospital admission+IV hydrocortisone+IV fluids
+Infliximab (resucue therapy)
2nd line: (no repsonse to steroids/infliximab) colectomy+ileo-anal pouch or ileostomy
Azathioprine (purine anti-metabolite- T cell apoptosis) - if >2 steroids/yr
- monitor TPMT level, FBC+LFT (SE: hepatitis, leucopenia, increased risk squamous cell carcinoma)
Surgery: panproctocolectomy with permanent end ileostomy
colectomy with temporary end ileostomy (later, ilestomy reversed and ileorectal anastomosis formed)
Coeliac disease
Autoimmune disease triggered by gluten in wheat, barley, rye, oats Immune activation (T cell) in small bowel causes villous atrophy and malabsorption
Risk fx: HLA DQ2, HLA DQ8
Sx: diarrohoea, steatorrhea, abdo pain, bloating
Signs: IDA (common), dermatitis herpetiformis, anguular stomatitis
Ix: FBC (IDA), serum B12/folate/iron, Anti-TTG (checl IgA), Anti-EMA (endomysial antibody), intestinal biopsy with on gluten diet:
- subtotal villous atrophy, intra-epithelial lymphocytes, crypt hyperplasia
Tx: gluten free diet+Vit D+Calcium
Complications: Anaemia, increased risk of gastric Ca., lymphoma
Bowel obstruction(small and large)
Surgical emergency where a mechanical obstruction (complete/partial) stops flow of intestinal contents
Simple obstruction (occlusion with blood supply) or strangulated (bloody supply to involved segment is cut off e.g. strangulated hernia, volvulus)
Causes:
In lumen: faecal impaction, gallstone ileus
In wall: Chron’s, carcinoma
Outside wall: strangulated hernia, volvulus, adhesions
Small bowel: Causes: previous surgery - adhesions hernia Crohn's
Large bowel: Causes: Colorectal Ca. (most common) Volvulus (sigmoid, caecal) Diverticular stricture
Sx: colicky abdop pain, vomiting, absolute constipation, abdo distention,
Signs: tympanic abdo (high pitched on percussion (due to gas)), abdo mass (carcinoma), hernia, scars
Determine simple and strangulated obstruction
Raised temp, signs of peritonitis - continuous pain, rigid abdo, raised WBCs
Ix:
initial: Abdo XR (3:6:9: small bowel >3m, large bowel: 6cm, caecum >9cm)
Small bowel: dilated loops at centre, plicae circulares which completely crosses lumen
Perforation: free air under diaphragm, thumbprinting
Definitive: CT
Large bowel Sigmoid volvulus (Inverted U shape, coffee bean, arises in left lower quadrant and extends toward right upper, no haustra) Caecal volvulus (arises in right lower quadrant extends to left upper, can see haustra, dilated small bowel with distal colon collapsed)
Biopsy: malignancy
Both:
UEs (urea raised - dehydration)
CT with gastrograffin: locate cause, distention
Tx: Drip and suck (NG tube, IV fluids), catheterise
SBO
Complete: emergency laparotomy+pre op abx
LBO
Sigmoid: sigmoid decompression + flatus tube
2nd line: Hartman’s (indications: compression failed, perforation)
Caecal: laparotomy (ileocaecal resection)
Ano-rectal sepsis
Fissure in ano: Tear at anal margin. Acute anal pain, esp after passage stool. Tx: lidocaine + GTN ointment
Abscess: infection of soft tissue around anus. Perianal: infected hair follicle Submucous: infected fissure Ischioanal: infected anal gland Sx: fever, signs sepsis Signs: perianal mass Tx: surgical drainage
Fistula in ano:
Abnormal communication between two epithelial surfaces
Causes: abscess, Crohn’s
Sx: abscess, discharge (mucus, blood), opening on perineum
Goodall’s rule (if external opening anterior to transverse anal line - fistula will follow straight course to anal canal, if external opening posterior to transvere anal line - follow curved course)
Ix: proctoscopy, MRI
Tx: surgery
Haemorrhoids
Abnormal swelling of anal cushoins (Normal vascular rich connective-tissue cushions in anal canal) causing symptoms
Due to straining, increase intra-abdo pressure e.g. pregnancy
Sx: painless rectal bleeding, perianal pain+palpable lesion
Ix: protoscopy
sigmoidoscopy/colonscopy (exclude malignancy)
Tx: high fibre diet, laxatives
rubber band ligation
haemorroidectomy
Hernias
Inguinal
Indirect: enters inguinal ring and passes canal
Direct: pushes through post. wall of inguinal canal
Risk fx: chronic cough, obese, pregnancy, constipation
Sx: asymptomatic. Pain in groin, constipation
M (sup): internal oblique m, transverse abdominus m.
Anterior: Internal and external oblique aponeurosis
Lateral: inguinal, lacunar ligament
T (bottom): conjoint tendon, transversalis fascia
Deep ring: midpoint between inguinal ligament
Superficial ring: superior and medial to pubic tubercle
Indirect: Common (80%), Passes through internal ring, lat. to inferior epigastric vessels
Can be congenital, acquired, high risk strangulation, extends down scrotum, rarely reduces on lying
Direct: 20%, Passes through post. wall, medial to inf. epigastric vessels, always acquired (rare in child), low risk strangulation, rarely extends into scrotum, can reduce on lying
Indirect: lateral to inferior epigastric vessels
Direct: medial to inferior epigastric vessels
Ix: clinical
Distinguish between direct/indirect:
Press on deep ring, ask pt to cough, if hernia still protrudes then direct
Complications: strangulation, bowel obstruction
Tx: open (Lichenstein technique) or laprascopic (transabdominal preperitoneal or total extra-peritoneal)
(mesh used to strengthen both both)
Complications: damage vas deferns or testicular vessels, chronic pain
Femoral:
Bowel protrudes through femoral canal
NAVY (femoral nerve, artery, vein, Y of groin) lat-medial
Femoral canal medial to femoral vein, and lateral to pubic tubercle (Femoral vein - femoral canal - pubic tubercle)
Canal contains fatty tissue, lymph node (LN of Cloquet)
Femoral hernia: inferior lateral to pubic tubercle
Inguinal hernia: super-medial to pubic tubercle
Risk fx: female, pregnancy, constipation
High risk strangulation due to rigidity of canal’s borders
Tx: surgery
DDx: inguinal hernia, enlarged, LN of Cloquet, lipoma
Incisional
Protrusion of contents of cavity through previously made incision
Risk fx: emergency surgery high BMI midline incision wound infection
Sx: non-pulsatile, reducible soft swelling near or at side of incision
Ix: clinical
Tx: sutures, laprascopic/open mesh
Layers of abdo wall
Skin Subcuteanous tissue Superficial fascia Ex oblique Internal oblique Transverse abdominus Trasnversalis fascia Peritoneum
Surgical wounds
Heal by primary intention (wound edges close together) with end result, return to normal with minimal scarring
Haemostasis, inflammation, proliferation, remodelling
Factors affect wound healing:
Blood supply
Infection
Co-morbidties i.e diabetes
Stoma
Colostomy: Left iliac fossa, flush (no spout)
Loop colostomy: loop of colon bought to surface, rod used to stop bowel from falling back in
Temp divert faeces (to protect distal anastomosis), easily reversed e..g anterior resection
End colostomy: bowel divided, proximal end bought to surface, distal can be:
resected (abdominoperineal resection: no anus)
closed and left in (Hartmann’s)
Illeostomies: Right iliac fossa, has sprout (as emits enzymes which damages skin)
Loop illeostomy: defunction colon e.g. perianal Crohn’s
End illeostomy: total/subtotal colectomy e.g. UC (illeo-anal anastomosis (ileum attached to anterior rectum)
Urostomies:
After total cystectomy
Brings urine from ureters to abdominal wall
Complications:
Early: haemorrhage, high output (lead to hypokalaemia)
Late: obstruction, parastomal hernia, pyschological problems
