Abdominal Flashcards
Persistence of the Vitello-Intestinal Duct
Vitelline Fistual (meconium through umbilicus)
Proximal part only = Meckel’s Diverticulum
Does not communicate with ileum = Enterocystoma
Persistent umbilical portion of the duct, which forms a polypoidal raspberry-like tumour of the umbilicus = Entroteratoma
Meckel’s Diverticulum
Remnant of vitello-intestinal duct
Located on anti mesenteric border of the ileum
2% (of the population)
2 feet (proximal to the ileocecal valve)
2 inches (in length)
2 types of common ectopic tissue (gastric and pancreatic)
2 years is the most common age at clinical presentation
2:1 male:female ratio
Complications: Bleeding Obstruction Herni (Littre's) Diverticulitis Neoplastic change
Urachus
Urachus is a fibrous remnant of the allantois, a canal that drains the urinary bladder of the fetus that joins and runs within the umbilical cord.
Runs from apex of the bladder to the umbilicus
Normally obliterated
Persistence can cause:
- Discharging umbilicus sinus
- Cyst
- Urinary fistula
Umbilical Sepsis
Neonatal
Causes serious complications:
- Portal thrombophlebitis
- Liver abscess
- Jaundice
- Portal vein thrombosis
- Liver failure
Adults
Caused by retention of sebum within folds of umbilicus or from pilonidal sinus infection of umbilicus
Erythematous
Mixed staphylococcus and streptococcus growth
Haematoma of the rectus sheath
Spontaneous rupture of a branch of the inferior epigastric artery –> haematoma in rectus sheath
Presents as abdominal pain + rigidity on one side
More common in elderly people on anticoagulation
USS used to Dx
Mx: Conservative or drainage if problematic
Desmoid Tumour
Rare tumour of fibrous intra-muscular septa in the lower rectus abdominis
More common in females CBA
Associated with Gardener’s syndrome (AD polyposis with intra colic and extra colic tumours)
Mx: excised widely as high recurrence and can undergo malignant transformation (fibrosarcoma)
Littre’s Hernia
Hernia of Meckel’s Diverticulum
Richter’s Hernia
Hernia only involving part of the circumference of the bowel wall
Do not present with usual obstructive features
May present with ileum due to peritonism caused by necrotic bowel
Amyand’s Hernia
Hernia of incarcerated appendix
Sliding inguinal hernia
Herniating viscus forms part of the of the wall of the hernia sac
Pantaloon Hernia
Direct and indirect inguinal hernia
Hernias straddle inferior epigastric artery with bulges either side
Borders of the Inguinal Canal
Anterior: External oblique aponeurosis
Lateral 1/3: +Internal oblique
Floor: Inguinal ligament
Reinforced by lacunar ligament medial end
Posterior: Transversalis fascia
Roof: Internal oblique, transversis abdominis (and transversalis fascia)
Location of Deep Inguinal Ring
1cm above the Mid-point of the inguinal ligament
1/2 way along the inguinal ligament that arises at the ASIS and inserts on the pubic tubercle
Bound medially by inferior epigastric artery
Deep ring is defect in the transversalis fascia
Location of the Superficial Inguinal Ring
Just above and medial to the pubic tubercle
Defect in external oblique aponeurosis
Reinforced by medial and lateral crura
Contents of the Inguinal Canal
M: Spermatic Cord
F: Round ligament
Ilioinguinal nerve
- Doesn’t enter through the deep ring
- At -risk during hernia repair
- Sensation to external genitalia
Genital branch of the the genitofemoral nerve
- Supplies crmaster muscle
- Anterior scrotal skin / mons pubis + labia majora
Coverings of the spermatic cord
Embryologically, takes a covering from each layer of the abdominal wall
Transversalis fascia –> Internal spermatic fascia
Internal oblique –> cremasteric muscle and fascia
External oblique –> external spermatic fascia
Contents of the spermatic cord
Spermatic cord contents “3 arteries, 3 nerves, 3 other things”:
3 arteries:
- Testicular artery (branch of aorta on R, branch of renal artery L)
- Deferential artery (artery to the ductus deferens)
- Cremasteric artery (branch of inferior epigastric)
3 nerves:
- Genital branch of the genitofemoral
- Cremasteric nerve
- Autonomics.
3 other things:
Ductus deferens
Pampiniform plexus
Lymphatics
Ilioinguinal nerve
Hernia passes above and medial to pubic tubercle
INGUINAL HERNIA
Hernia passes below and lateral to pubic tubercle
FEMORAL HERNIA
Hesselbach’s Triangle
Medial: lateral border of the rectus abdominis
Lateral: Inferior epigastric artery
Below: Inguinal ligament
(Above: Conjoint tendon)
Managemet of uncomplicated inguinal hernia
Neonate –> emergency
Children –> elective herniotomy
Symptomatic adults –> offered surgery
Indications for laparoscopic hernia repair
Bilateral hernias for repair
Recurrent hernia
Exploration of the groin when a symptomatic
hernia is suspected from
Age at which conservative management for umbilical hernia is switched to surgical management:
3 years
-95% resolve by then
Surgery to correct para-umbilical hernia
Mayo procedure
-Flap of rectus sheath and line alba above and below defect
Foramen of Winslow
foramen, between the greater sac (general cavity of the abdomen)
and the lesser sac
anterior: the free border of the lesser omentum, known as the hepatoduodenal ligament. This has two layers and within these layers are the common bile duct, hepatic artery, and hepatic portal vein. A useful mnemonic to remember these is DAVE: Duct, Artery, Vein, Epiploic foramen.
posterior: the peritoneum covering the inferior vena cava
superior: the peritoneum covering the caudate lobe of the liver
inferior: the peritoneum covering the commencement of the duodenum and the hepatic artery, the latter passing forward below the foramen before ascending between the two layers of the lesser omentum.
left lateral: gastrosplenic ligament and splenorenal ligament
Visceral referred pain from the abdominal cavity
Foregut: lower oesophagus to second part of duodenum –> Epigastric
Midgut: second part of duodenum to to splenic flexure –> Umbilicus
Hindgut: Splenic flexure to rectum –> Hypogastrium
Boas’s sign
In acute cholecystitis, pain radiates to the tip of the scapula and there is a tender area of skin just below the scapula, which is hyperaesthetic.
Causes of Raised Amylase
Pancreatic conditions
• Acute pancreatitis
• Pancreatic cancer
• Pancreatic trauma
Other intra-abdominal pathology • Perforated peptic ulcer • Acute appendicitis • Ectopic pregnancy • Intestinal infarction • Acute cholecystitis
Decreased clearance of amylase
• Renal failure
• Macroamylaseaemia
Miscellaneous
• Head injury
• Diabetic ketoacidosis
• Drugs (e.g. opiates)
Causes of free sub-diaphragmatic gas
- Perforation of an intra-abdominal viscus
- Gas-forming infection
- Pleuroperitoneal fistula
- Iatrogenic: laparoscopy, laparotomy
- Gas introduced per vaginam: post-partum
- Interposition of bowel between liver and diaphragm
Common Sites for Intra-Abdominal Abscess
Subphrenic space
Subhepatic space
Pelvis
Between loops of bowel
‘pus somewhere, pus nowhere else, pus under the diaphragm’.
Anatomy of the Appendix
Blind ended tube situation on the posteromedial aspect of the caecum 2cm below the ileocaecal valve
Average 6-9cm in length
Found at the convergence of the three taenia coli
Has its own mesentry - mesoappendix
Supplied by the appendicular artery which is a branch if the ileocolic artery
Appendix Mass or Abscess
Mx Non-Operative as long as no peritonitis
Antibiotics and percutaneous drainage if abscess
Colonoscopy at 6 weeks to rule out malignancy
Appendix positions
Retrocaecal
Pelvic
Subcaecal
Paracaecal
Pre-ileal
Post-ileal
Pelvic most common on laparoscopy
Retrocaecal most common on cadaveric
Stimulants for release H2 from parietal cells
Vagus nerve acetylcholine
Gastrin
Inhibition of H2 from parietal cells
Somatostatin
Gastric inhibitory peptide
Vasoactive intestinal peptide (VIP)
Pepsin Cells
Found in body and fundus of stomach
Produce Pepsinogen
–> Pepsin
Stimulated by acteylcholine from vagus nerve
Nissen Fundoplication
Hiatus hernia reduced
Crura approximated
Fundus mobilised from underside of diaphragm
Fundus wrapped posteriorly around lower oesophagus and attached to left side of proximal stomach (360 wrap)
Others:
Toupet: 270
Watson: 180
Components of lower oesophageal sphincter
Physiological high pressure area in lower oesophagus
Mucosal rosette of the cardia
Angle of oesophagus as it meets the cardia - Angle of His
Diaphragmatic sling / crura
Positive intra-abdominal pressure at lower end of oesophagus
Hiatus hernia
Sliding: 90%
Stomach slides through diaphragmatic hiatus, grastro-oesophageal junction lies in thorax
–> Lower sphincter incompetent
Rolling: 10%
Para-oesophageal
Cardia remains below diaphragm: sphincter competent
Stomach rolls up anteriorly through hiatus
(Mixed)
Ivor Lewis Oesophagectomy
Two stages
Laparotomy
Stomach fully mobilised on vascular pedicle
Left gastroepiploic and gastric artery divided
Right thoracotomy
Oesophagectomy
Bring up stomach
Anastomasois
Feeding jejunostomy
Trans-hiatal Oesophagectomy
Abdominal incision
Mobilise oesophagus through hiatus
Cervical oesophagus by left neck incision
Pharyngeal Pouch
Killian’s Dehiscence
Between thyropharyngeus and cricopharyngeus
Posterior pharyngeal pouch
Mx: Endoscopic stapling
Heller’s Myomotomy
Lower oesophageal sphincter divided 5cm above junction and 3cm below
+Anterior partial fundoplication to reduce subsequent GORD
Achalasia
Failure of relaxation of lower oesophageal sphincter and associated ineffective peristalsis
Degeneration of myenteric plexus of Auerbach
Mx
Balloon dilatation
Surgical: Heller’s
Management of diffuse oesophageal spasm
Calcium channel blockers
Sublingual GTN
PPI
Causes of peptic ulcers
H.Pylori
NSAIDs
Smoking
Zollinger-Ellison syndrome
Hyperparathyroidism –> hypercalcaemia
Blood group O
Surgical management of gastric ulcers
Failure to heal with medical therapy –> indication for surgery
Benign distal ulcers: Billroth I gastrectomy
-Distal stomach removed and proximal stump anastomosed with duodenum
Proximal ulcers: Polya-Type reconstruction
- Anastomosis of gastric remnant to jejunum
Complications of Gastrectomy
Dumping
- Early
- Late
Diarrhoea
Anaemia
Osteoporosis + Osteomalacia
Nutritional deficiencies
Carcinoma
- Reflux of bile salts
- Should be offered endoscopic surveillance
GIST
Dx: EUS
<2cm –> discharge
2-5cm –> surveillance
> 5cm –> resect
Meneteriers Disease
Gastric mucosal hypertrophy
Mucosal folds in body and fungus grossly enlarged
Leads to over-secretion of acid and mucus
Increased risk of malignancy –> prophylactic gastrectomy
Dumping
Early: True 15-30 minutes post meal Vasomotor symptoms Tachycardia Flushing Light-headedness Sweating --> Rapid emptying of hyperosmolar (mainly carbohydrates) into small bowel --> Influx of fluids down osmotic gradient
Late
4 hours
–>Reactive hypoglycaemia
Zollinger-Ellison Syndrome
Gastrinoma
Normally in pancreas but can be in duodenum or stomach
MEN 1: 30%
Present with diarrhoea and pain
–> Peptic ulceration
Liver surface anatomy
5th intercostal down to right costal margin
Extends to left mid-clavicle
Bilirubin level of clinical jaundice
50
Right Hepatic and Right portal vein supply
Right hemiliver
Lobes V - VIII
Left Hepatic and Left portal vein supply
Left hemiliver
I –> Caudate
II and III –> Left lobe
IV –> Quadrate
Causes of portal hypertension
Pre-Hepatic
Congenital atresia of portal vein
Portal vein thrombosis: Neonatal Sepsis, Pyelophlebitis, Trauma, Tumour
Extrinsic compression: Pancreatic, Biliary
Hepatic:
Cirrhosis
Schistosomiasis
Post-Hepatic:
Budd-Chiari syndrome
Cosntrictive pericarditis
(Increased blood flow due to arteriovenous fistula or hyperspenlism)
Hydatid Cyst
Tapeworm infection:
Echinococcus granulosus
E. Multiocularis
Adult tapeworm lives in intestine of dog
Ingested ova hatch in duodenum –> portal venous sytem
Leads to cyst with a surrounding fibrosis of the adventitial layer
Rupture can lead to anaphylaxis
Eosinophilia
Mx: Mebendazole
Pyogenic liver abscess pathogens
Strep milleri E.coli Strep faecalis Staph aureus Anaerobes
Amoebic liver abscess
Entamoeba histolytica
Intestine –> trophozoites –> portal vein –> Liver
Right lobe ascess with thin-walles
Solitary
Stool: Ameobae cysts
Mx of Acites
Spironolactone
Fluid restriction and Salt restriction
+/- LeVeen shunt for refractory ascotes
Peritoneum –> external jugular
Budd Chiari
Portal HTN
Caudate hypertrophy
Liver failure
Gross ascites
Compenents of Child Score
Encephalopathy
Ascites
Bilirubin
Albumin
Prothrombin ratio
Antibiotic prophylaxis in Varices
Ciprofloxacin 500mg BD
Diagnosis of HCC
If resection planned do NOT biopsy
Diagnosis
Two imaging modalities showing arterial hypervascularisation (regardless of AFP)
OR
Single modality showing lesion + AFP >400
OR
Histological diagnosis <2cm
Mx of HCC
Resection when possible
Chemo: Doxorubicin, 5-flurouracil,
Sorafenib: Tyrosine kinase inhibitor
Milan Criteria
Criteria for liver transplant in HCC
Sinlge tumour <5cm
3 or less tumours no bigger than 3cm
Angiosarcoma of the liver
Vinyl chloride
Thorotrost
Liver cell adenoma
Require resection as may undergo malignant change
Assoc oral contraceptive pill
Right flank pain due to haemorrhage
Solitary well encapsulated
Nearly always in F
Focal nodular hyperplasia of the liver
Do not require resection, do not undergo malignant transformation
Central fibrous scar seen on CT
F>M
Cavernous haemangioma
Commonest benign liver tumour
Pain, swelling and haemorrhage
If arteriovenous communication develops can lead to high output heart failure
Mx: Resection if large
Biliary hamartoma
Small fibrous lesion just beneath liver capsule
Biopsy usually needed to rule out HCC
Course of biliary system
Right and left hepatic ducts converge to make the common hepatic duct
Joined by the cystic duct to form common bile duct
Passes behin first part of the duodenum
Passes close to head of pancreas
Joins Pancreatic duct just prior to ampulla of vater
Post-Cholecystectomy Syndrome
Post-prandial flatulence
Fat intolerance
Epigastric and right hypochondrium discomfort
Asiatic chlangiohepatitis
Pigment stones form in the intrahepatic and extrahepatic biliary tree
Supparative cholangitis
E.Coli
Strep Faecalis
–> Deconjugation of bilirubin –> stones
Mx:
Endoscopic or percutaneous removal of stones
Ductal obsruction
- Choledoduodenostomy
- Hepatojejunostomy
Klatskin tumour
Sclerotic cholangiocarcinoma involving the confluence of the hepatic ducts
Intrahepatic duct dilataion and collapsed gallbladder
=cholangiosarcoma
obstruction above cystic duct at hepatic ducts
Biliary Atresia
1 / 20,000
Commonest cause of prolonged jaundice in infancy
Jaundice at 2-3 weeks of life
Hepatomegaly and splenomegaly
Mx: Early Kasai’s
If identified late –> transplant
Infections in bile
E. Coli
Klebsiella
Strep facealis
Cholechondral cysts
Cystic transformation of the biliary tree
Saccular dilatation of the common bile duct
–> often abnormal termination as the common bile duct enters pancreatic head to join pancreatic duct
Undergo malignant transformation
Mx: Excision
Complications of acute pancreatitis
Infected pancreatic necrosis
Pancreatic pseudocyst
Pancreatic abscess
Progressive jaundice
Gastrointestinal bleeding (splenic artery)
Gastrointestinal ischaemia/fistulae
Management of chronic pancreatitis
Conservative:
- Stop cause
- CREON
- Glucose control
Endoscopic:
-Stenting
Surgical
- Beger
- Frey
Pancreatic ductal adenocarcinoma (PDAC)
60% arising in the head
characterized by groups of infiltrating carcinoma cells often some distance apart, interspersed by a fibrous stroma
involvement of nerves, vessels, lymphatics and lymph nodes
Metastatic spread is most commonly to the liver and lung; 80%
Intraductal papillary mucinous neoplasm (IPMN)
Group of lesions characterized by a papillary growth of
the ductal epithelium with rich mucin production and cystic expansion of the affected duct
Two types,
1) Main duct: Definite malignant potential –> Resection
2) Branch duct: Most;ly benign, resect if >3cm or if septae/nodularity
Survival reaching 80–90% for in situ carcinoma,
and 50–70% in the presence of invasive carcinoma
Differ from cystic mucinous
- Direct communication with the Wirsung duct
- Absence of ovarian-type stroma
Mucinous cystic neoplasm
F»M
Multiloculated tumours with a characteristic dense fibrous wall and occasional calcification
Oversecretion of the mucus by the hyperplastic columnar lining of the ducts and therefore contain thickened viscous material,
Can be haemorrhagic.
These tumours should be considered potentially malignant but are classified histologically as benign, borderline, or malignant based on degree of dysplastic changes.
Serous cystic neoplasm
Serous cystic neoplasms are most commonly Microcystic
Can present in an ‘oligocystic’ or ‘macrocystic’ form when differentiation from other cystic neoplasms can be difficult.
In the presence of multiple serous cysts Von Hippel–Lindau syndrome should be considered
Present as incidental findings or with pressure symptoms or a palpable mass when large.
Dense, internal, lacelike, honeycombed matrix
composed of fibrous septae, and often a central scar.
Diagnosis preoperatively, resection is usually not required as serous cystic tumours have virtually
no malignant potential.
Acinar cell carcinoma of the pancreas
Tumour cells also may secrete pancreatic
enzymes, most commonly lipase.
Presentation may therefore be confused with acute pancreatitis
Whipples
Block resection of the:
-Head of the pancreas
- Distal half of the stomach
- Duodenum
- Gallbladder and common bile duct
Reconstruction is achieved by anastomoses of the pancreatic tail remnant to the jejunum (or stomach)
AND
Anastomosing the common hepatic duct and the stomach to the jejunum.
Tumours sited in the head of the pancreas Mx
Whipples
Tumours sited in the tail of the pancreas Mx
Distal pancreatectomy and Splenectomy
Most are unresectable
PET syndromes
MEN 1: 40%
von Hippel-Lindau 10-15%
Confusion, sweating, dizziness,
weakness, unconsciousness, relief
with eating
Insulinoma
Zollinger–Ellison syndrome or severe
peptic ulceration and diarrhoea
Gastrinoma
Necrolytic migratory erythema, weight
loss, diabetes mellitus, stomatitis,
diarrhoea
Glucagonoma
Werner–Morrison syndrome of
profuse watery diarrhoea with marked
hypokalaemia
VIPoma
Cholelithiasis; weight loss; diarrhoea
and steatorrhoea. Diabetes mellitus
Somatostatinoma
MEN-1
Hyperplasia and/or neoplasm of the parathyroid glands
Enteropancreatic NETs
Pituitary adenomas.
PPP
11q13 gene
Familial MEN-1: First degree relative with at least one of the Ps tumour
For PETs, 90% have multiple which is juxtaposed to sporadic-type tumours that tend to be solitary
It is recommended that carriers of MEN-1 mutation are screened biochemically every 1–3 years for hyperparathyroidism, prolactinoma, gastrinoma, insulinoma, and other enteropancreatic
tumours.
Indications for splenectomy
Trauma
Blunt / penetrating trauma
Iatrogenic intraoperative / endoscopic trauma
Haematological The purpuras Haemolytic anaemia Hypersplenism Proliferative disease
Misc Distal pancreatectomy (for benign or malignant disease) Proximal gastrectomy Splenorenal shunt
Post-splenectomy immunization
Pneumococcal vac repeat
Influenza immunization
Life long antibiotics are phenoxymethylpenicillin or erythromycin
If not previously immunized:
Haemophilus influenza type b
Meningococcal group C conjugate vaccine
Elective splenectomy should be preceded by the
administration of vaccines 2–3weeks prior to surgery
True rectum
Coalescence of the taeniae coli of the sigmoid colon
to form a continuous outer muscular tube
Faecal calprotectin
Nonspecific test of intestinal inflammation that can be used to monitor inflammatory bowel disease activity
Trotter’s triad
Diagnosis of nasopharyngeal carcinoma
- Unilateral conductive hearing loss
- Ipsilateral facial & ear pain
- Ipsilateral paralysis of soft palate
Tumours of the appendix
Carcinoid
-Appendicectomy sufficient unless >2cm or invokves caecum –> R hemicolectomy
Adenocarcinoma
-R hemicolectomy +/- chemo
Pseudomyxoma peritonei
-Seeding from cystadenoma of appendix
Indications for surgery Crohn’s
Elective
• Chronic subacute obstruction due to fibrotic strictures,
adhesions or refractory disease
• Symptomatic disease unresponsive to, or poorly
controlled by medical management
• Chronic relapsing disease on discontinuation of medical
management and steroid dependency
• Complications of medical management (e.g. osteoporosis)
• Concerns about long-term immunosuppression, risk of
malignancy and viral/atypical infections
• Perianal sepsis and fistula
• Enterocutaneous fistula
• Onset of malignancy, including colorectal
adenocarcinoma and small bowel lymphoma
• Rarely, control of debilitating extra-colonic manifestations such as iritis and sacroiliitis.
Emergency • Fulminant colitis or acute small bowel relapse unresponsive to medical management • Acute bowel obstruction • Life-threatening haemorrhage • Abscess or free perforation • Perianal abscess.
Indications for surgery UC
Elective
• Symptomatic disease unresponsive to, or poorly
controlled by, medical management
• Chronic relapsing disease on discontinuation of medical management and steroid dependency
• Complications of medical management
• Concerns about long-term immunosuppression, risk of
malignancy and viral/atypical infections
• Severe dysplasia on surveillance biopsies of colorectal
epithelium
• Onset of colorectal adenocarcinoma
• Rarely, control of debilitating extra-colonic manifestations such as iritis and sacroiliitis.
Emergency
• Fulminant colitis unresponsive to maximal medical
management
• Toxic megacolon
• Free perforation
• Life-threatening haemorrhage
• Acute complications of medical management.
GIST
Bengin and malignant
C-kit = malignant
–>imatinib
Peritoneal coverings of the rectum
Upper third: Anterior and sides covered in peritoneum
Middle third: Peritoneum anteriorly
Lower thid: Extraperitoneal
Superior rectal artery
Continuation of Inferior mesenteric artery
Communicates with middle and lower rectal arteries which are an extension of internal iliac artery
Drainage of inferior mesenteric vein
Drains into splenic vein
Lymph drainage of rectum
Drains upwards to Superior rectal and inferior mesenteric lymph nodes
Lymph drainage of anal canal
Drains to inguinal nodes
Position of the appendix
Medial wall of caecum
2cm below ileocaecal valve
Taenia coli converge at appendix
Management of bile salt diarrhoea
Seen in crohns
Cholestyramine
5-aminosalicylic acid agents
Mesalazine
Olsalazine
Used for maintenance therapy for people with colonic IBD
Indications for surgery in Crohns disease (4)
- Complications of luminal disease: fulminant colitis, life-threatening haemorrhage, obstruction, abscess, sepsis, perforation, fistulation
- Acute on chronic medical therapy failure / complications of medical therapy
- Treatment or prophylaxis of malignancy
- Peri-anal disease
Communication between superior mesentric artery and ceolicac axis
Pancreaticoduodenal arcade
Communication between superior mesenteric artery and inferior mesenteric artery
Marginal artery
Cells of the small bowel
Columnar glandular epithelium
APUD: Amine precursor uptake decarboxylation
Paneth cells
Test for bacterial overgrowth
C-Xylose
C-Glucochelote
Breath test
Tumour of APUD cells
Carcinoid
Most common sit eis appendix
Appendectomy
-if >2cm, nodal involvement or involves caecum –> R Hemicolectomy
Appendix adenocarcinoma
Assoc with Lynch syndrome
Mucin-secreting cyst adenoma
Pseudomyxoma peritoni
Truelove and Witts
Mild, Moderare Severe
Severe Stools / day: >6 Pulse: >90 Temp: >37.8 Hb <105 ESR >30 CRP >30
c-kit in GIST
=malignant
imatinib mesylate
Tyrosine kinase inhibitor
Used in GIST
Urinary 5-HIAA
Carcinoid tumour
Competent ileocaecal valve and large bowel obstruction
–> Caecal perforation
Largest diamter, Laplace law
Small bowel most susceptible to readiation enteritis
Jejunum
Typical electrolyte abnormalities causing ileus
Hypokalaemia
Hyponatraemia
Uraemia
DKA
Drugs that cause a paralytic ileus
Tricyclic antidepressants
Lithium
Excess opiates
Management of pseudo obstruction
Management is conservative and involves stimulant enemas.
Colonoscopic deflation may be required in cases where caecal distension
Intravenous erythromycin has been shown to stimulate motility by binding to colonic motilin receptors.
Intravenous neostigmine
Commonest site of diverticulosis
Sigmoid
Solitary diverticulum of caecum
Arise from medial wall close to ileocaecal valve
Rare
Can extend upwards retroperitoneally
If becomes obstructed and inflammed, clinically same as appendicitis
Management of uncomplicated diverticulitis
High fibre diet
Supplemented by bran or a bulk laxative such as
methylcellulose
Stimulant laxatives and purgatives are to be avoided.
Antispasmodics, such as propantheline or
mebeverine
NSAIDs increase complications - AVOID
Hinchley Grade
Severity of diverticulitis
I: localised para-colic abscess
II: distant abscess e.g. pelvis or sub-diaphragmatic
III: Peritonitis
IV: Faecal peritonitis
RET gene mutations
Associated with Hirschsprung’s disease
MEN II
DUKES: Spread to involve lymph nodes
Dukes C
DUKES: Spread through full thickness
of bowel wall
Dukes B
DUKES: Metastatic
Dukes D
DUKES: Spread into, but not beyond,
muscularis propria
Dukes A
Indications for radiotherapy for rectal carcinoma
High-risk tumours
Risk factors include
- Low tumour
- Bulky fixed lesion
- Anterior lesion
- Evidence of T3 or T4 stage and/or involved lymph nodes on imaging.
Indications for chemotherapy for colorectal cancer
Post-operative chemotherapy for Dukes C and D
Combine capecitabine with oxaliplatin
New Abs
Cetuximab: monoclonal antibody against epidermal growth factor receptor
Bevacizumab: monoclonal antibody to vascular endothelial growth factor
Position of anorectal cushions
3, 7, and 11 oclock
Corrospond to three terminal branches of superior rectal artery
Left
Right posterior
Right anterior
Cell lining below dentate line
Keratinised squamous cell
Cell lining transition zone of anal canal
Non-keratinised squamous cell
Cell lining anal canal above transition zone
Columnar epithelium
Structures maintaining faecal continence
Intact anorectal and pelvic floor sensation
Intact anal sphincters and levator ani
Preservation of the anorectal angle
The bulk provided by the anal haemorrhoidal ‘cushions’.
Staging of haemorrhoids
First-degree piles are those that bleed, are visible on
proctoscopy but do not prolapse
Second-degree piles are those that prolapse during
defaecation but reduce spontaneously
Third-degree piles are prolapsed constantly but can be reduced manually
Fourth-degree piles are irreducibly prolapsed.
Sites of ano-rectal abscess
Peri-anal: common, simple drainage
Intersphincteric: common
Ischiorectal: can become bilateral as no fascial planes - usually require drainage and antibioitcs
High-intermuscular: more complex, can become circumferential
Pelvirectal: more complex, can become circumferential
Goodsall’s Rule
Anterior opening of fistula on perianal skin: Radial tracking of fistula directly into anal canal
Posterior opening: Line can be drawn between
3 o’clock and 9 o’clock positions
then the tract usually passes circumferentially backwards and enters the anal canal in the midline (6 o’clock position)
Management of fistulas-in-ano
Low fistulae should be laid open
Complex high fistulae require repair and/or seton insertion
- Advancement flap
- +/- defunctioning
Types of fistula-in-ano
Low intersphinteric
Trans-sphinteric
Supra-sphincteric
Ischiorectal fistula
Causes of fistula-in-ano
Common • Idiopathic (cryptoglandular) due to blockage of anal gland duct • Crohn's disease • Anorectal trauma • Iatrogenic (surgical) • Anorectal carcinoma
Rare causes
• Ulcerative colitis
• Tuberculosis
• Actinomycosis
Mx of anal warts
Topical podophyllin
Anal verge cancer lymph spread
Inguinal lymph nodes
Anal canal lymph spread
Proximal to mesorectal nodes or internal iliac nodes via the middle rectal lymph nodes
Management of anal cancer
T1N0 lesions: Local surgical excision only
T2, T3, or T4 lesions: Chemoradiotherapy
- external beam radiotherapy
- capecitabine and mitomycin / capecitabine and cisplatinum
Abdominoperineal resection is reserved for failures of
chemoradiation.
Management of rectal prolapse
Childhood rectal prolapse
- Conservative
- Regular bowel habits and reduction of the prolapse
Mucosal prolapse
- submucosal injection of sclerosant, by photocoagulation or by applying Barron’s bands to the prolapsed area
- resistant cases: limited excision of the area or stapled anorectal rectopexy
Full-thickness Perianal Approach -Delorme's procedure -Perianal rectosigmoidectomy -Altmeier procedure
Abdominal approach
-Laparoscopic rectopexy and resection of the redundant sigmoid colon
Solitary rectal ulcer syndrome
Inordinate amount of time in the toilet attempting
to defaecate
Diagnosis: Anterior ulcer in the low rectum, and biopsy shows submucosal fibrosis, hypertrophy of the muscularis mucosae and overlying ulceration
Mx
Stool softners and psych
Traumatic cause of anal incontinence
Obstetric sphincter injury
Trauma
Surgical / iatrogenic (drainage or perianal abscess, fistula opening, haemorrhoidectomy)
Perianal sepsis
Congenital causes of anal incontinence
Anorectal atresia
Spina bifida
Neurological causes of anal incontince
Denervation of pelvic floor following childbirth
Multiple sclerosis
Low spinal or sacral tumour
Spinal trauma
Dementia
Treatment of idiopathic faecal incontinence
Avoiding dietary stimulants
Fybogel + loperamide
Treatment of rectal irritability
Amitriptyline 25mg ON
