General Surgery

Question 1

Appendicitis

Answer 1

Pathophysiology: pathogens trapped → inflammation + infx → gangrene + rupture → peritonitis

Sx:
Abdominal pain (umbilical → RIF (< 24 hrs))
Tender at McBurney’s point (1/3rd distance from ASIS to umbilicus)
Rovsing’s sign = palpation of LIF → pain in RIF
PR exam → pain in RIF
Features of general upset: anorexia + N&V + pyrexia

Diagnosis = clinical. Sx but normal inflammatory markers → diagnostic laparoscopy. Consider CT/USS to exclude other diagnoses.

Tx = urgent admission + refer surgery + prophylactic IV ABX + appendicectomy (laparoscopic)

Question 2

Complications of appendicitis

Answer 2

Appendix mass = omentum sticks to appendix → mass in RIF. Tx = supportive (with ABX) → appendectomy when acute phase resolves

Question 3

Features of peritonitis

Answer 3

Rebound tenderness in right iliac fossa + Percussion tenderness

Caused by rupture (e.g. appendix)

IX = erect CXR (shows air under diaphragm)

Question 4

Bowel obstruction

Answer 4

Small bowel intestine more commonly affected.

Pathophysiology: obstruction →↓ passage of food/fluid/gas →↑ proximal pressure → vomiting + dilation of proximal bowel (Surgical emergency) →↓ fluid absorption → hypovolaemic shock (a.k.a. third-spacing).

Causes (>90% due to below):
(1) Adhesion (small bowel) due to abdo/pelvic surgery + peritonitis + infx + endometriosis.
(2) Hernia (small bowel) – think obturator hernia
(3) Malignancy (large bowel)

Symptoms:
o Green bilious vomiting
o Abdominal distention + diffuse pain
o Absolute constipation (absence of flatulence)
o Tinkling bowel sounds (early sign)

diagnosis = AXR showing dilated bowel (small bowel >3cm or colon>6cm or caecum > 9cm)

Other Ix: ABG (metabolic alkalosis due to vomit + raised lactate) + contrast CT + erect CXR (exclude air under diaphragm)

TX = drip and suck = A-E + NBM + IV fluids with added potassium + NG tube with free drainage + pain relief.
o Stable → conservative
o Unstable → surgical therapy (e.g. emergency resection / stent)

Bowel obstruction = CI to metoclopramide

Question 5

Closed loop obstruction

Answer 5

Definition: 2 points of obstruction in bowel → middle section unable to drain → continuous dilation of middle section → ischeamia → perforation

Causes: adhesions + hernias + volvulus + single obstruction with competent ileocecal valve (ileocecal valve behaves as obstruction if there is additional obstruction in distal colon)

Treatment = emergency surgery

Question 6

Ileus

Answer 6

Definition:
o Ileus = transient loss of peristalsis in small intestine.
o Pseudo-obstruction = functional obstruction of large bowel (no mechanical cause). Less common than ileus.

Aetiology (anything that disrupts small intestine) = injury + handling of bowel in surgery + inflammation of nearby tissue (e.g. pancreatitis) + electrolyte imbalance.

Clinical features = bowel obstruction Sx + absent bowel sounds

Treat underlying cause + supportive care (NBM + NG tube + IV fluids + parenteral nutrition).

Question 7

Volvulus

Answer 7

Bowel twists arounds → closed-loop bowel obstruction → ischaemia → necrosis → perforation. 2 types:
Sigmoid volvulus = affecting sigmoid. More common. RF = chronic constipation + elderly + high fibre diet + excessive use of laxatives.
Caecal volvulus = affecting caecum. Less common. Affects younger patients.

Risk factors: neuropsychiatric disorder (e.g. Parkinson’s) + elderly + chronic constipation + high fibre diet + pregnancy + adhesion

Clinical features = bowel obstruction Sx

Ix = AXR (coffee bean sign = sigmoid) + contrast CT (diagnostic)

Tx = A-E + supportive (drip and suck).
Conservative treatment = endoscopic decompression (using flexible sigmoidoscope). Risk of reoccurrence is 60%. Only indicated in sigmoid volvulus.
Surgical = laparotomy / Hartmann’s procedure / ileocecal resection / right hemicolectomy. If bowel obstruction perform emergency laparotomy.

Question 8

Symptoms and treatment of hernia

Answer 8

Clinical features = Soft lump protruding from abdominal wall. Initially reducible. May protrude on coughing / standing. May be accompanied by aching, pulling or dragging sensation.

Treatment:
o Conservative = hernia is left. Most appropriate if wide neck hernia + not surgical candidate
o Surgical = Tension free repair = mesh placed over defect in abdominal wall (mesh acts as scaffold for new tissue to heal over). Lower rate of recurrence but high rate of complications.

Question 9

Define:
incarceration of herna
Obstruction of hernia
Strangulation of hernia

Richter’s hernia
Maydl’s hernia

Answer 9

Incarceration = irreducible = hernia cannot be pushed back into place. Bowel trapped in herniated position. The wider the neck the lower the risk of this (important to assess on exam)
Obstruction = blockage to passage of contents within bowel of hernia
Strangulation = compression at neck of irreducible hernia → ischaemia → necrosis (within hrs). Sx = significant pain at herniation site + obstruction. Surgical emergency.
Richter’s hernia = can occur with any abdominal hernia. Rare. Only part of bowel wall herniates through abdominal wall → ischaemia of bowel wall → rapid necrosis. Surgical emergency. Sx = Sx of strangulation without Sx of obstruction.
Maydl’s hernia = 2 different loops of bowel contained within same hernia

Question 10

Inguinal hernia (indirect vs. direct)

Answer 10

95% are male. Found above and medial to pubic tubercle.
 Indirect = bowel herniates through deep inguinal ring and into inguinal canal.
 Direct = bowel herniates through Hesselbach’s triangle (in abdominal wall) into inguinal canal

Examination to differentiate indirect vs. direct = reduce hernia and apply pressure at deep inguinal ring (mid-point from ASIS to pubic tubercle):
• Indirect hernia = will remain reduced with pressure at deep inguinal ring
• Direct hernia = will not remain reduced with pressure at deep inguinal ring

Strangulation is rare (~3% per year). More common in indirect hernias.

Question 11

Femoral hernia

Answer 11

Hernia through femoral ring into femoral canal

below and lateral to pubic tubercle.

High risk of obstruction/strangulation (as femoral ring is narrow). More common in women.

Tx = surgical repair required.

Question 12

Obturator hernia

Answer 12

Herniation of abdominal/pelvic organ through obturator foramen of pelvis.

RF = defect in pelvic floor (female + older age + pregnancy + vaginal delivery).

Sx = irritation of obturator nerve (→ medial thigh pain). Howship-Romberg sign = pain on inner thigh to knee during hip internal rotation (→ compression of nerve). Commonly present with bowel obstruction.

IX = CT / MRI

Question 13

Other types of hernia (Incisional + umbilical + epigastric + spigelian + diastasis recti)

Answer 13

Incisional hernia = found at site of previous surgery (due to weakness of previous incision). Difficult to repair and high recurrence (conservative Tx preferred). Seen in 10% of ops.

Umbilical hernia = herniation around umbilicus. Umbilical → symmetric bulge. Paraumbilical → asymmetric bulge. Common in neonates. Resolve spontaneously. 

Epigastric hernia = hernia in epigastric area.

Spigelian hernia = between lateral border of recuts abdominis and linea semilunaris (site of spigelian fascia which is aponeurosis between muscles of abdominal wall). Usually found in lower abdomen. Ix = USS. Narrow neck so high risk of incarceration / strangulation / obstruction.
 
Diastasis recti  = widening of linea alba between rectus muscles (not technically a hernia). Can be congenital / pregnancy / obesity. No Tx required.

Question 14

Hernias in children

Answer 14

Congenital inguinal hernia = indirect hernias resulting from patent processus vaginalis.
 Occur in 1%. RF = premature + male. 60% right sided, 10% bilaterally.
 Tx = surgical repair ASAP (risk of incarceration)

Infantile umbilical hernia = Symmetrical bulge under umbilicus.
 RF = premature + Afro-Caribbean.
 Tx = self-resolve before age of 4-5 years. Complications are rare

Question 15

Hiatus hernia

Answer 15

Definition: herniation of stomach through oesophageal hiatus . Types:
o Type 1 = sliding = stomach slides through diaphragm with gastro-oesophageal junction passing into thorax
o Type 2 = rolling = fundus of stomach folds around and enters through diaphragm
o Type 3 = combination of type 1 and 2
o Type 4 = large hernia allowing additional abdominal organs to pass through diaphragm

Risk factors = old age+ obesity + pregnancy

Sx = heartburn + Dysphagia + regurgitation + chest pain

Ix = endoscopy / barium swallow (most sensitive). Can be intermittent therefore negative investigations does not exclude.

Treatment:
o Conservative (Tx of GORD
o Laparoscopic fundoplication (indicated if high risk of complications / Tx resistant Sx)

Question 16

Chronic mesenteric ischaemia (intestinal angina)

Answer 16

Atherosclerosis of mesenteric vessels → chronic ischaemia of intestines → intermittent abdo pain

RF = angina RF = age + FMH + smoking + HTN + cholesterol

Clinical features – classic triad:
Central colicky abdominal pain after eating
Weight loss (due to food avoidance)
Abdominal Bruit

Investigation = CT angiography

Tx = Tx modifiable risk factors + secondary prevention of atherosclerosis (e.g. stains + antiplatelet) + revascularisation. Options for revascularisation:
1st line = endovascular procedure (e.g. percutaneous mesenteric artery stenting)
2nd line = open surgery (e.g. endarterectomy / bypass grafting)

Question 17

Acute mesenteric ischaemia

Answer 17

thrombus/emboli → sudden occlusion of superior mesenteric artery → acute ischaemia of midgut → necrosis → perforation

Risk factors = atrial fibrillation

Clinical feature = Acute, non-specific abdominal pain (pain disproportionate to examination findings) + shock ± peritonitis ± sepsis

Ix = contrast CT. Other findings: metabolic acidosis + raised lactate (due to organ ischaemia)

Treatment = surgery (immediate laparotomy to remove necrotic bowel + thrombus in artery)

Prognosis = mortality >50%

Question 18

Define:
o Diverticulum
o Diverticulosis
o Diverticular disease
o Diverticulitis

Answer 18

o Diverticulum: pouch or pocket in bowel wall.
o Diverticulosis: presence of multiple diverticula without inflammation / infection.
o Diverticular disease: diverticulosis + symptoms.
o Diverticulitis: inflammation + infection of diverticula.

Question 19

Diverticular disease

Answer 19

Pathophysiology: weak areas of bowel wall = areas not covered by teniae coli + points where circular muscles are penetrated by blood vessels. ↑ pressure in bowel → hernia of mucosa through weak areas of walls (diverticula). Do not spread into rectum as reinforced by outer longitudinal muscle layer. Most commonly affects sigmoid colon.

Risk factors: age + low fibre + obesity + NSAIDs.

Clinical features:
Lower left abdominal pain
Constipation
Rectal bleeding

Investigations: colonoscopy / CT scan

Management (step wise).
(1) Wt loss + high fibre diet + good hydration.
(2) Bulk forming laxatives (ispaghula hulk). Avoid stimulant laxatives (senna).
(3) Surgical resection if severe symptoms

Question 20

Acute diverticulitis

Answer 20

Clinical features: severe Sx of diverticular disease (e.g. severe pain in LIF) + systemically unwell (e.g. diarrhoea / N&V) ± Palpable abdominal mass (if abscess formed).

Investigations: bloods (raised inflammatory markers) + CT scan

Management:
Uncomplicated → manage in primary care = ABX (co-amoxiclav 5 days) + liquid diet (i.e. avoid solid foods) + analgesia (avoid NSAIDs / opioids).
Severe pain / Sx > 72 hrs → admit for IV ceftriaxone + metronidazole ± surgery

Complications: Perforation / Peritonitis / Peri-diverticular abscess / Large haemorrhage / Fistula (between colon + bladder/ vagina) / Ileus / obstruction

Question 21

Haemorrhoids

Answer 21

Enlarged anal vascular cushions. Usually found at 3, 7 and 11 O’clock (with patient in lithotomy position)

RF = age, pregnancy, obesity, constipation, increased straining, increased intra-abdominal pressure (weight-lifting/ chronic coughing).

Classification:
o 1st degree = no prolapse.
o 2nd degree = prolapse when straining + return on relaxing.
o 3rd degree = do not return on relaxing but can be pushed back.
o 4th degree = prolapsed permanently.

Clinical features:
o Painless, bright red bleed (typically on toilet tissue) - blood not mixed in with stool.
o Sore/ itchy anus
o Feeling a lump around or inside anus.

PR findings:
o External (prolapsed) haemorrhoids = visible on inspection as swellings covered in mucosa.
o Internal haemorrhoids = felt upon PR exam / appear when bearing down (grade 2/3)

Investigations = proctoscopy (required for visualisation) + consider testing for anaemia

Management:
o Soften stools: increase dietary fibre and fluid intake
o Topical local anaesthetics + steroids may be used to help symptoms
o Outpatient Tx = rubber band ligation (1st line) / injection sclerotherapy (2nd line)
o Surgery = large symptomatic haemorrhoids which do not respond to outpatient Tx
o Newer treatments = Doppler guided haemorrhoidal artery ligation, stapled haemorrhoidopexy

Question 22

Thrombosed haemorrhoids

Answer 22

strangulation / thrombosis at base of external haemorrhoids → very painful, tender + purplish, odematous swollen lumps around anus.

PR exam impossible due to pain. Will resolve (can take weeks).

Tx:
< 72hrs since Sx onset → surgery.
> 72 hrs → ice pack + analgesia + stool softeners

Question 23

Anal fissure

Answer 23

Tear in squamous lining of distal anal canal. Acute = <6 wks. Chronic = >6wks.

90% found in posterior midline – alternative location consider underlying cause (e.g. Crohn’s) and are red flag for bowel cancer (2WW)

RF = constipation + IBD + STI

Sx = painful bright red rectal bleed

Treatment:
Acute = soft stools = diet + bulk forming laxatives ± lubricant / topical anaesthetic
Chronic = topical GTN (1st line). GTN not effective <8wks → refer surgery (sphincterotomy / botulinum toxin)

Question 24

Perianal abscess

Answer 24

Collection of pus in subcut tissue of anus. Infx may or may not be present (due to E.coli / staph aureus).

Associations = Crohn’s

Sx = pain around anus (worse on sitting) ± pus like discharge

Ix = Clinical diagnosis. Consider trans-perineal USS (gold standard) .

Tx = incision + drainage (1st line). Wound should be left open/packed (heals in 3-4wks).

Question 25

Anal fistula

Answer 25

Abnormal connection between epithelium of skin and anal canal due to previous ano-rectal abscess.

Sx = persisting discharge after ano-rectal abscess.

Goodsall’s rule determines location.

Ix =MRI.

Tx: lay open (uncomplicated) or insert seton (if complex).

Question 26

Types of abdominal incision:
• Midline
• Paramedian (+ Battle)
• Kocher’s
• Gable
o Lanz
o Gridiron
• Pfannenstiel’s
• McEvedy’s
• Rutherford Morrison

Answer 26

• Midline = most common. Divides linea alba + transversalis fascia + extraperitoneal fat + peritoneum
• Paramedian = parallel to midline + rectus abdominis retracted (Battle = paramedian incision but rectus displaced medially (causing denervation). Rarely used)
• Kocher’s = under right subcostal margin (usually open cholecystectomy)
• Gable = roof top incision (i.e. along both subcostal margins)

Used for appendectomy:
o Lanz = right iliac fossa (1st line)
o Gridiron = oblique incision over McBurney’s point (less cosmetically acceptable)

• Pfannenstiel’s = transverse suprapubic (used for pelvic organs, e.g. C-section)
• McEvedy’s = groin incision
• Rutherford Morrison = extraperitoneal approach to iliac vessels (used in renal transplant). Leaves hockey stick scar.

Question 27

Abdominal wound dehiscence

Answer 27

Definition: separation of abdominal wound allowing protrusion of viscera.

Risk factors: Malnutrition + Vitamin deficiencies + jaundice + Steroid use + Major wound contamination (e.g. faecal peritonitis) + Poor surgical technique

Treatment:
o Cover wound with saline impregnated gauze
o IV ABX + fluids + analgesia
o Immediate return to theatre

Question 28

Splenectomy (indications / complications / ongoing treatment)

Answer 28

Indications:
o Trauma
o Spontaneous rupture secondary to EBV
o Hypersplenism – think haemolytic anaemia
o Malignancy – lymphoma / luekaemia
o Other: splenic cyst / hydatid cyst / splenic abscess

Complications:
o Increased risk of infx/sepsis due to: pneumococcus + haemophilus + meningococcus + capnocytophaga canimorsus (think dog bites)
o Blood film changes = Howell-Jolly bodies + target cells + pappenheimer bodies
o Other: haemorrhage / pancreatic fistula / thrombocytosis

Prophylactic Tx required after splenectomy:
o Vaccinations (required 2 wks before elective splenectomy) = Hib + Men ACWY + annual influenza + pneumococcal every 5 yrs
o Penicillin V (at least 2 yrs some require for life)
o Aspirin (treat thrombocytosis)