Surgery - Abdominal wall surgery

Question 1

What is the definition of a hernia?

Answer 1

Protrusion of a viscus beyond the normal coverings of the cavity in which it is normally contained
Can be acquired or congenital

Question 2

What does a hernia consist of?

Answer 2

1) sac
2) coverings
3) contents

Question 3

Name 5 types of hernia, and say which one is most likely to strangulate

Answer 3

1) Incisional
2) Epigastric
3) Inguinal (direct and indirect)
4) Umbilical
5) Femoral -> most likely to strangulate as the borders are 70% bone

Question 4

Describe hernia complications which can arise

Answer 4

1) pain/inflammation
2) irreducible (due to narrowed neck/adhesions meaning it cannot be returned to the cavity from which it originated)
3) incarcerated (irreducible, lumen is blocked but blood supply is intact i.e. not strangulated)
4) strangulated (blood supply cut off -> can lead to ischaemia and necrosis, perforation and septic shock)

Question 5

Describe the causes of a hernia

Answer 5

Increased intra abdominal pressure (exercise, coughing, straining, sneezing) and weakened abdominal wall (older age, malnutrition, muscle/nerve paralysis)

Question 6

How is a hernia investigated?

Answer 6

Examination
Herniogram (CT + contrast)
USS (for scrotal lumps, used to exclude hydrocoele)

Question 7

What are the layers of the abdominal wall?

Answer 7

1) skin
2) subcut fat
3) fascia = campers and scarpas
4) external oblique muscle (check?)
5) internal oblique muscle
6) transverse abdominus
7) transversalis fascia
8) preperineal fat
9) peritoneum

Question 8

Describe the anatomy of the inguinal canal

Answer 8

Inguinal ligament runs from ASIS -> pubic tubercle
The deep ring is found at the midpoint of the inguinal ligament
This is the path which the testes takes on descent into the scrotum
The superficial ring is found closer to the pubic tubercle
Walls:
M - superior = muscles (internal oblique and transverse abdominus)
A anterior = aponeurosis (of internal and external oblique muscles)
L = lower = ligaments (lacunar and inguinal)
T = transversalis fascia and conjoint tendon

Question 9

Describe the difference between a direct and indirect inguinal hernia and how to distinguish between the two on examination

Answer 9

Direct = passes through the abdominal wall, will still pop out when you place your finger over the patients deep ring and ask them to cough!

Indirect = passes through the inguinal canal and comes out the superficial ring, will NOT pop out when you place your finger over the patients deep ring and ask them to cough

Question 10

What are the treatment options for a hernia?

Answer 10

1) elective -> contents of hernia returned to abdomen and defect repaired with sutures/artificial mesh
- > usually laparoscopic

2) emergency = if incarcerated/strangulated, may need bowel resection

Question 11

What are the issues with using mesh for hernia repair?

Answer 11

Can increase risk of infection in incarcerated/strangulated hernias

Question 12

What common bacteria can infect surgical wounds?

Answer 12

Skin commensals

• Staph aureus
• Staph epidermis

Contaminants from other organ systems during surgery

• gut (E.coli)
• biliary tree (pseudomonas)

Question 13

How should a possibly infected surgical wound be investigated and treated?

Answer 13

Send pus -> MC & S
MRSA swab
Blood cultures
? wound aspiration
? antibiotics

Question 14

What is dihiscence of a surgical wound?

What are the risk factors for it occuring?

Answer 14

Opening go the wound, usually secondary to infection
May lead to evisceration into the abdomen

RFx: immunosuppression, malnutrition, steroids, poor surgical technique, previous surgery

Question 15

What is a stoma?

Answer 15

• An external opening within a luminated organ into the outside world
• Can be temporary or permanent

Question 16

What are the 5 most common types of stoma formed in surgery?

Answer 16

1) ileostomy -> bring out mid/distal small bowel, can be loop or end
2) colostomy -> bring out large bowel, can be loop or end
3) urostomy -> one/both ureters diverted into a short length of disconnected bowel (usually a piece of ileum)
4) gastrostomy = connection between stomach and anterior abdominal wall, for drainage or feeding
5) jejunostomy = connection made between the proximal jejunum and anterior abdominal wall, used for direct feeding

Question 17

What is the difference between and end and loop stoma and their functions

Answer 17

• Loop = often temporary
  distal bowel intact
  used to provide bowel rest and protect distal bowel anastomoses
  e.g. used after an anterior resection
• End = the bowel is divided and the proximal end is brought out as a stoma and the distal and stitched shut

Question 18

When creating a stoma, which sites should be avoided?

Answer 18

umbilicus
bony prominences
old scars/wound sites -> may have underlying adhesions
skin folds/creases/waistline

Always check the chosen site with the patient sitting and standing before surgery

Question 19

How can an ileostomy and colostomy be differentiated on examination?

Answer 19

Ileostomy - right sided, spouted with prominent mucosal folds
Colostomy - left sided, usually flat with the abdomen and flat mucosal folds

Question 20

How can a urostomy be distinguished from an ileostomy on examination?

Answer 20

A urostomy is indistinguishable from an end-ileostomy unless the output from the stoma can be seen

Question 21

Where are gastrostomies/jejunostomies usually located?

Answer 21

In the LUQ, usually fitted with indwelling tubes/access devices

Question 22

Name some early complications of stomas

Answer 22

haemorrhage
ischaemia
increased output can lead to hypokalaemia (give loperamide to sort this!)
obstruction
stoma resection

Question 23

Name some late complications of stomas

Answer 23

dermatitis at the site
obstruction
prolapse/intusseption
stenosis
parastomal hernia
fistulae
psychological