General Flashcards
How does an indirect inguinal hernia arise?
Failure of embryonic closure of deep inguinal ring, with hernial sac being the patent processus vaginalis
How does a direct inguinal hernia arise?
Through a weak spot in the posterior wall of inguinal canal (transversalis fascia)
Describe the relationship of indirect vs direct inguinal hernias to the inferior epigastric artery
Direct - medial to inferior epigastric
Indirect - lateral to inferior epigastric
What is Hesselbach’s triangle?
Where direct inguinal hernias occur
medial border: lateral border of rectus abdominis
Superolateral: inferior epigastric vessels
Inferior border: inguinal ligament
How can one clinically distinguish between indirect and direct inguinal hernias?
Reduce hernia by gently pushing upwards and laterally
Place index and middle fingers on deep inguinal ring surface and ask patient to cough
If direct: hernia appears medial to examiner’s two fingers
If indirect: no lump
What are the contents of the inguinal canal in males vs females?
Males - spermatic cord + ilioinguinal nerve
Females - round ligament of the uterus + ilioinguinal nerve
What are the contents of the spermatic cord?
3 arteries: cremasteric, testicular, vas deferens
3 nerves: cremasteric, genital branch of the genitofemoral nerve, autonomics
3 other things: lymphatics, ductus deferens, pampiniform plexus
What are the boundaries of the inguinal canal?
2 MALT: 2M 2A 2L 2T
Superior: 2 Muscles -internal oblique muscle, TA muscle
Anterior wall: 2 Aponeuroses
- Aponeurosis of EO
- Aponeurosis of IO
Lower wall: 2 Ligaments
- Inguinal ligament
- Lacunar ligament
Posterior wall: 2Ts
- Transversalis fascia laterally
- Conjoint tendon medially
What is the difference between the midinguinal point and the midpoint of the inguinal ligament?
Midinguinal point: midway between the ASIS and the pubic symphysis
Midpoint of the inguinal ligament: midway between the ASIS and the pubic tubercle
What is a Hartmann’s procedure and when is it indicated?
Surgical resection of the rectosigmoid colon, brining colon surface to create a colostomy, and closure of rectal stump. Colostomy can be reversed at a later time.
Indicated in sigmoid CRC or diverticulitis
List two differences in appearance between ileostomies and colostomies.
Ileostomy found in R lower quadrant, colostomy found in L lower quadrant
Ileostomy has full thickness eversion of the bowel (minimise excoriation) while colostomy made flush with skin (effluent is usually solid and thus is non-irritative)
When is a permanent end ileostomy indicated?
Permanent - after proctocolectomy for inflammatory bowel disease or familial polyposis
But development of newer sphincter-saving procedures means that it is no longer used as oftenetc.)
When is a temporary end ileostomy indicated?
In conjunction with subtotal abdominal colectomy for toxic colitis, L sided large bowel obstruction or ischaemic bowel
i.e. when anastomosis between ileum and colon/rectum risky due to ischaemia or severe sepsis etc.
When is a loop ileostomy indicated? (2)
- To protect a distal anastomosis i.e. in an ileal pouch-anal anastomosis or low colorectal anastomosis
- To divert stool from distal anorectum e.g. severe perineal trauma, perianal faecal incontinence
How does a loop ileostomy work?
Afferent (functioning) limb produces stool output
Efferent limb (defunctioned, smaller) allows passage of flatus and mucous discharge
When is a permanent end sigmoid colostomy indicated? (2)
In rectal resection
Alleviation of severe incontinence
List 7 stoma complications
- Obstruction
- Ischaemia
- Bleeding and ulceration
- Appliance leakage
- Stenosis, retraction, prolapse
- Peristomal excoriation (common around ileostomies due to irritant nature of small bowel fluid in skin)
- Dehydration due to excessive fluid loss
List 5 causes of small bowel obstruction. Which two are the most common?
Adhesions Hernias Neoplasms Strictures: Crohn's disease, ischaemia Gallstone ileus
Adhesions and hernias are most common
What are the clinical features of small bowel obstruction?
If proximal: nausea and vomiting (early presentation)
If distal: 2-3 day history of crampy abdominal pain prior to vomiting and distension and constipation
Bowel sounds initially hyperactive and high-pitched - in delayed presentation, may be decreased secondary to ileus
How should suspected SBO be investigated? (4)
- Bloodwork - FBE (increased WCC may indicate perforation), lactate (sign of ischaemia), UECs for metabolic disturbance
- Abdo x-rays: supine and erect
- erect will show if there is any perforation (free gas under diaphragm)
- supine will show dilated small bowel proximal obstruction with air-fluid levels - Contrast radiography with gastrografin - determines extent of obstruction and also has mild therapeutic effect
- CT if clinical and radio graphic findings inconclusive
How should SBO be managed? (2)
- Conservative - NBM, NGT tube insertion, IV fluid and electrolyte replacement, analgesia?
- Surgery in patients who show signs of peritonism or who are less well
What are the 3 main causes of large bowel obstruction?
Carcinoma of colon/rectum - 50% of cases
Sigmoid volvulus
Diverticular disease
In which population does a sigmoi volvulus most commonly occur?
Condition of the elderly and frail who have a long history of constipation and laxatives
What are the clinical feature of large bowel obstruction?
Abdo pain
Distension due to retention of faeces and flatus
Constpiation
Peritonism if perforation has occurred
Vomiting = late symptoms (consider competency of ileocaecal valve)