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Flashcards in General Surgery - SBO + LBO Deck (92)
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1

What is a hernia? 

The protrusion of a viscus or part of a viscus through a defect of the walls of its containing cavity into an abnormal position

2

What is the difference between irreducible, obstructed, strangulated and incarcerated hernias? 

  • Irreducible: contents cannot be pushed back into place
  • Obstructed: bowel contents cannot pass—features of intestinal obstruction 
  • Strangulated: ischaemia occurs—the patient requires urgent surgery.
  • Incarceration: contents of the hernial sac are stuck inside by adhesions.

3

What is the difference between the indirect and direct hernias?

  • Direct inguinal hernia (20%)
    • Bowel enters the inguinal canal “directly” through a weakness in the posterior wall of the canal -  Hesselbach’s triangle
    • More common in older patients, often secondary to abdominal wall laxity or a significant increase in intra-abdominal pressure
    • Medial to the inferior epigastric vessels.
  • Indirect inguinal hernia (80%)
    • Bowel enters the inguinal canal via the deep inguinal ring
    • Arise from incomplete closure of the processus vaginalis, an outpouching of peritoneum allowing for embryonic testicular descent (so are seemed to be congenital in origin) - hence more common in children
    • Lateral to the inferior epigastric vessels

NB: These two types of inguinal hernia can only be reliably differentiated at the time of surgery re relation to vessels 

4

Which of the two are more dangerous?

  • Direct - less common. Reduce easily and rarely strangulate 
  • Indirect - More common. Can strangulate 

5

What are the risk factors for developing hernias?

  • Male
  • Increasing age
  • Raised intra-abdominal pressure (Chronic cough, heavy lifting, or chronic constipation)
  • Chronic 

6

What makes up the floor, roof, anterior and posterior walls of the inguinal canal?

  • Floor: Inguinal ligament and lacunar ligament medially
  • Roof: Fibres of transversalis, internal oblique
  • Anterior: External oblique aponeurosis + internal oblique
  • Posterior: Laterally, transversalis fascia; medially, conjoint tendon.

7

What are the clinical features of hernia? 

  • Lump in the groin - if reducible hernia will initially disappear with minimal pressure or when the patient lies down.
  • If incarcerated - painful, tender, and erythematous.
  • ? Clinical features of bowel obstruction -  if the bowel lumen blocked
  • ? Features of strangulation* if the blood supply becomes compromised.
  • If lump visible - ask pt to reduce it
  • Cough impulse - Remember that an irreducible hernia may not have a cough impulse
  • ? Reducible – On lying down +/- minimal pressure

8

What position do we expect to see inguinal hernias? 

  • Inguinal (superomedial to the pubic tubercle)
  • Femoral (inferolateral to the pubic tubercle)
  • This is not always clear on examination

9

How would you differentiate between an indirect and direct hernia on examination? 

  •  Reduce hernia and occlude the deep (internal) ring (midpoint of inguinal ligament) with two fingers.
  • Ask the patient to cough or stand
  • If the hernia is restrained, it is indirect; if not, it is direct.
  • Above is often unreliable. Gold standard: in surgery with relation to epigastric vessels

10

How are hernias managed? 

Surgery 

  • If symptomatic, offer surgery
  • Risk of strangulation would require urgent surgical intervention
  • Open repair - Lichtenstein technique most commonly used or 
    • Open mesh repairs - a polypropylene mesh reinforces the posterior wall - prevents reoccurence
    • Preferred for those with primary inguinal hernias  
  • Laparoscopic approach
    • Total extraperitoneal (TEP)
    • Transabdominal pre-peritoneal (TAPP)).
    • Preferred* in those with bilateral or recurrent inguinal hernias.
    • Also for certain pt with a primary unilateral hernia -  at a high risk of chronic pain (young and active, previous chronic pain, or with a predominant symptom of pain)
    • Females (due to the increased risk of the presence of a femoral hernia).
  • Post surgical:  Rest for 4wks and convalescence over 8wks with open approaches, but laparoscopic repairs may allow return to manual work (and driving) after ≤2wks if all is well

11

When are femoral hernias more common? 

  • More common in women than men (ratio 3:1), because of the wider anatomy of the female bony pelvis
  • Middle age
  • Elderly

12

How are femoral hernias repaired? 

  • Surgical repair is recommended. 
  • Herniotomy is ligation and excision of the sac
  • Herniorrhaphy is repair of the hernial defect.

13

What is the location of the femoral hernia?

 Found infero-lateral to the pubic tubercle (and medial to the femoral pulse)

14

How should femoral hernias be managed? 

Surgically, ideally within 2 weeks of presentation, due to the high risk of strangulation.

  1. Low approach – the incision is made below the inguinal ligament, which has the advantage of not interfering with the inguinal structures but does result in limited space for the removal of any compromised small bowel
  2. High approach – the incision is made above the inguinal ligament is the preferred technique in an emergency intervention due to the easy access to compromised small bowel

The operation involves reducing the hernia and then narrowing the femoral ring with sutures medially between the pectineal and inguinal ligaments or with a mesh plug .

15

What are the serious complications of hernias that require intervention? 

  • Strangulated - compression of hernia has blood supply is compromised, resulting in the bowel becoming ischaemic 
  • Irreducible - the contents of the hernia are unable to return to their original cavity 
  • Obstructed - the bowel lumen has become obstructed, leading to the clinical features of bowel obstruction

16

How is diarrhoea clasified? 

  • Diarrhoea: 3 or more loose stools or stools with increased liquid per day (as defined by the WHO)
  • Acute diarrhoea: < 14 days
  • Chronic diarrhoea: > 14 days
  • Dysentery: Gastroenteritis characterised by loose stools with blood and mucus
  • Travellers’ diarrhoea: More than 3 loose stools commencing within 24 hours of foreign travel, with or without cramps, nausea, fever, or vomiting

17

What are the clinical fx of gastroenteritis? 

  • Cramp-like abdominal pain
  • Diarrhoea (with or without blood or mucus)
  • Associated vomiting
  • Night sweats
  • Weight loss 
  • On examination, the patient will often be dehydrated (of varying  severity) with potential pyrexia.

18

What are some of the viral and bacterial causes of gastroenteritis? 

  • Viral: adenovirus, norovirus, adenovirus
  • Bacteria (all are gram -ve bacillus)
    • Campylobacter - the most common cause of food poisoning 
    • E. Coli – Gram -ve bacillus, typically transmitted through contaminated foodstuffs. 
      • Enterotoxigenic E. coli (ETEC) is the most common cause of Travellers’ diarrhoea
    • Salmonella – Gram -ve flagellated bacillus (two serotypes most commonly associated with gastroenteritis, S. typhimurium and S. enteritidis), transmitted through undercooked poultry or raw eggs; results in fever, vomiting, abdominal cramps, and bloody diarrhoea

    • Shigella – Gram -ve bacillus, from contaminated dairy products and water; presents with fever, abdominal pain, or bloody diarrhoea

19

What is more likely to be the causative organism of travellers diarrhoa and can you provide any examples? 

  • Parasites: Cryptosporidium, Entamoeba histolytica, Giardia intestinalis, Schistosoma

20

What is the main pathogen for hospital acquired gastroenteritis? 

How does this happen?

  • C. difficile, a Gram positive organism
  • Develops following the use of broad-spectrum antibiotics, disrupting the normal microbiota of the bowel
  • C. difficile bacteria excessively overgrows and then produces large amounts of exotoxins A & B
  • Exotoxins A+B -> inflammatory exudate on the colonic mucosa -> severe bloody diarrhoea, which can turn into toxic megacolon

21

How do you investigate and treat C.Diff? 

  • Investigation: stool culture and C. difficile Toxin (CDT) testing*.
  • Treatment: IV fluid rehydration and oral metronidazole; Vancomycin -  severe disease or if no improvement is seen after 72 hours.

22

What is angiodysplasia? 

  • Most common vascular abnormality of the gastrointestinal tract
  • It is caused by the formation of arteriovenous malformations between previously healthy blood vessels, most commonly in the caecum and ascending colon.
  • Second commonest cause of rectal bleeding in those >60yrs; it is the most common cause for bleeding from the small bowel.

23

How does angiodysplasia present? 

  • rectal bleeding and anaemia. 
  • Assymptomatic 
  • Painless occult PR bleeding (majority of case)
  • Acute haemorrhage

24

How would you investigate angiodysplasia? 

  • Blood tests: FBC*, U&Es, LFTs, and clotting. Group and Save or Crossmatch (if need for transfusion), haematinics (iron deficiency anaemia) 
  • Imaging:
    • Exclude any malignancy - OGD/ colonoscopy/ FOB (depending on the suspected site of bleeding)
    • Wireless capsule endoscopy: for small bowel bleeds 
    • Mesenteric angiography - to confirm location of a lesion in order to plan for intervention as necessary. 
    • Angiography + radionuclide scanning, CT scanning, or MRI scanning to image the GI tract vascular supply after the injection of a radio-opaque contrast agent into the vessels.

25

How do you manage angiodysplasia?

  • Conservative: bed-rest and IV fluid support, tranexamic acid
  • Medical:
    • Endoscopy: argon plasma coagulation - treat bleeding vessel with electrical current
    • Other endoscopic techniques: monopolar electrocautery, laser photoablation, sclerotherapy, and band ligation.
  • Mesenteric angiography
    • Used for small bowel lesions that cannot be treated endoscopically.
    • Contrast dye is used to identify the bleeding vessel then super-selective catheterisation and embolization of it
  • Surgical: bowel resection and anastomoses of an affected section

26

How does acute appendicitis present?

  • Classically periumbilical pain that moves to the rif.
  • Pain over McBurneys point
  • Tachycardia
  • Fever
  • Peritonism with guarding and rebound or percussion tenderness in RIF
  • Lying still + shallow breathing
  • Pain on right during PR examination suggests an inflammed, low-lying pelvic appendix.
  • Anorexia!
  • Constipation
  • Possible diarrhoea

27

What three specific tests (on examination) suggest appendicitis?

  • Rovsing’s sign (pain > in rif than lif when the lif is pressed)
  • Psoas sign (pain on extending hip if retrocaecal appendix)
  • Cope sign (pain on flexion and internal rotation of right hip if appendix in close relation to obturator internus).

28

What investigations should you perform for acute appendicitis? 

  • Bedside: urine dipstick, pregnancy test 
  • Blood tests: FBC: neutrophil leucocytosis, UE, CRP (elevated)
  • 1st line imaging: USS 
  • 2nd line: CT 

29

What risk stratification scores are used for appendicitis? 

  • Men – Appendicitis Inflammatory Response Score
  • Women – Adult Appendicitis Score
  • Children – Shera score

30

How do you manage appendicitis? 

  • Laparoscopic appendicectomy
    • Appendix should be sent to histopathology 
  • ABx: Piperacillin/tazobactam 4.5g/8h, 1-3 doses iv starting 1h pre-op, reduces wound infections. Give a longer course if perforated