GI S3 (Done) Flashcards Preview

ESA 3 Callum's Cards > GI S3 (Done) > Flashcards

Flashcards in GI S3 (Done) Deck (91)
Loading flashcards...
1
Q

Describe the basic features of the abdominal wall

A

Continuous

Subdivided into:

Anterior

Lateral walls (left and right)

Posterior wall

Lateral and anterior wall boundary is indefinite therefore the term ‘anterolateral abdominal wall’ is used to describe them together

2
Q

Describe the boundaries of the anterolateral abdominal wall

A

Superiorly:

Xiphoid process

Cartilages of the 7th - 10th ribs

Inferiorly:

Inguinal ligament

Superior margin of the pelvic girdle (iliac crests, pubic crests and pubic symphisis)

3
Q

What are the layers of the abdominal gut wall?

A

Skin

Subcutaneous tissue (superficial fascia and fat)

Muscles and their apneurosis

Deep fascia

Extraperitoneal fat

Parietal peritoneum

4
Q

Label the black boxes

A

Top to bottom, right column first:

Skin

Superficial fatty layer of subcutaneous tissue

Deep membranous layer of subcutaneous tissue

Investing (Deep) fascia - superficial, intermediate and deep

2nd Column:

External oblique

Internal oblique

Transversus abdominus

Extraperitoneal fat

Endoabdominal fascia

Parietal peritoneum

5
Q

What is the umbilicus?

A

Center of anterolateral abdominal wall

L3

6
Q

What is the Epigastric Fossa?

A

Slight depression in epigastrum

Just inferior to xiphoid process

Heartburn commonly felt at this site

7
Q

What is the linea alba?

What is a common abnormality?

A

Apneuroses of abdominal muscles

Separates the left and right rectus abdominis

Visible in lean individual

Apneuroses of right and left, Intermediate and deep layers of the gut wall interweave here

If lax then rectus abdominis spread apart on contraction (Divercation of recti)

8
Q

What is the inguinal groove?

A

Skin crease parallel and just inferior to inguinal ligament

Marks the division between abdominal wall and thigh

9
Q

What are the Semilunar lines?

A

Slightly curved, tendinous lines on either side of the rectus abdominis

10
Q

What are the tendinous intersections of the rectus abdominis?

A

Clearly visible (in lean individuals) horizontal lines through the rectus abdominis

11
Q

What are the Arcuate lines?

A

Where the inferior limit of the posterior rectus sheath ends

1/3 of the way between the umbilicus and the pubic crest

12
Q

Label the Boxes

A

Top to bottom:

1st column:

Xiphoid process

Right costal margin

Umbilicus

Iliac crest

ASIS

Inguinal ligament

Pubic tubercle

2nd Column:

Epigastric fossa

Linea alba

Semilunar lines

Pubic symphysis

3rd Column

Serratus anterior

Ext. Oblique

Rectus abdominis

Linea alba

Umbilicus

Inguinal ligament

13
Q

There are two types of muscle in the abdominal wall, what are they and what are the muscles in each category?

A

Flat:

External oblique

Internal oblique

Transversus abdominis

Vertical:

Rectus abdominis

Pyrimidalis

14
Q

What directions do the fibres of the flat muscles of the abdominal wall run?

What is the order of the flat muscles in the abdominal wall?

A

External oblique:

Posterior to anterior

Superficial

Internal oblique:

Anterior to posterior

Middle

Transversus abdominis:

Transverse

Deep

15
Q

What is the rectus sheath?

A

3 flat muscles are continued antero-medially as the the rectus sheath (apneuroses) that enclose the rectus abdominis and Pyrimidalis

16
Q

Label the boxes

A

1st Column:

Rectus sheath

Rectus abdominis

Linea alba

Rectus sheath

2nd Column:

Apneuroses of TA

Parietal peritoneum

Transversalis fascia

TA muscle

Int. Oblique

Ext. Oblique

Subcutaneous tissue

Apneuroses of Ext. Oblique

Lamina of apneuroses of Int. Oblique

Skin

Parietal peritoneum

Extraperitoneal fat

Transversalis fascia

Membranous and Fatty layers of Subcutaneous tissue

17
Q

What are the major considerations when designing a surgical abdominal insicion

A

Capable of closing

Strong and long lasting

Minimise incidence of insicional herniae

Not directly through muscle (Sutures will ‘cut out’)

18
Q

List the major abdominal incisions

A

Midline

Transverse

Appendicectomy

Gridiron

19
Q

Breifly describe a midline surgical incision

A

Insicion through linea alba

20
Q

Briefly describe a transverse surgical incision

A

Cut through the external oblique apneuroses

21
Q

Describe an appendicectomy incison

A

Incision at McBurney’s point

2/3 the distance between umbilicus and ASIS

Through a Gidiron muscle splitting incision

22
Q

What is a Gidiron incision?

A

Separation of the muscle fibres of the flat muscles with scissors to get through to the peritoneum

23
Q

What is a ‘patent urachus’ and what is a common consequence?

What are the common causes?

A

Urachus connects the bladder and umbilicus, when patent allows urine to leak from the umbilicus

Causes:

Congenital

Benign prostatic hypertrophy in older men

24
Q

What is the vitelline duct?

What are the abnormalities that can be caused by it’s persistence?

A

A duct that connects the midgut to the yolk sac in the embryo

Abnormalities:

Meckel’s Diverticulum

Vitelline Cyst

Vitelline Fistula

Omphalocoele

Gastoschisis

25
Q

Describe a Meckel’s Diverticulum?

A

Most common GI abnormality

Cul-de-sac in the ileum

Rule of 2’s:

  • 2% of pop. affected
  • 2ft from ileocecal valve
  • 2 inches long
  • Usually detected in <2’s
  • 2:1 Male:Female

Can be asymptomatic

OR

Can contain ectopic gastric/pancreatic tissue that secretes enzymes and acid causing ulceration

26
Q

What is a vitelline cyst?

A

The vitelline duct forms a cyst connected to the lieum and abdominal wall via thin fibrous strands

27
Q

What is a vitelline fistula?

A

Direct communication between umbilicus and intestinal tract

This can result in faecal matter coming out of the umbilicus

28
Q

What is an Omphalocoele?

A

Persistence of physiological herniation

Part of the gut tube fails to return to the abdominal cavity following its normal herniation into the umbilical cord

Epithelial layer around the umbilical cord (Amnion) covers the defect

29
Q

What is Gastroschisis?

A

Failure of closure of the abdominal wall during embryo folding

Leaves the gut tube and its derivatives outside the body

There is no covering of the gut tube as they herniate directly through the abdominal wall into the amniotic cavity

30
Q

Label these 3 abnormal structures

A

Meckel’s Diverticulum

Vitelline cyst

Vitelline fistulla

31
Q

How does somatic pain become referred?

A

Noxious stimlus to proximal part of a somatic nerve is percieved in the distal dermatome

E.g. Shingles affects nerves, but is felt distally along nerve course to the infection

32
Q

How does visceral referred pain come about?

A

In the abdomen and thorax visceral afferent pain fibres follow sympathetic fibres

Course back to the same spinal cord segments that ive rise to the pre-ganglionic sympathetic fibres

CNS therefore percieves pain as coming from the somatic portion of the body supplied by the relevant spinal cord segments

33
Q

What can cause visceral pain?

A

Ischaemia

Abnormally strong muscle contraction

Stretch

ONLY

34
Q

Where in the abdomen might visceral referred pain be felt and what regions of the gut are actually producing pain in each case?

A

Epigastric region:

Foregut pain

Umbilicus region:

Midgut pain

Suprapubic region:

Hindgut pain

35
Q

Identify the source of the pain shown in the diagram

A

Gallbladder

36
Q

Identify the source of the pain shown in this diagram

A

Hepatic Pain (Liver)

37
Q

Identify the source of pain shown in this diagram

A

Splenic Pain

38
Q

Identify the possible sources of the pain shown in the diagram

A

Gastric (Stomach)

Duodenal

39
Q

Identify the source of the pain shown in this diagram

A

Oesophageal Pain

40
Q

Identify the possible sources of the pain in this diagram

Explain the distribution

A

Pancreatic

Abdominal aorta

Distribution:

Retroperitoneal structures can cause central back pain

41
Q

Identify the source of the pain shown in the diagram

Explain the change

A

Acute appendicitis

Early:

Pain begins in umbilicus because innervation of appendix enters spine at that level

Late:

Localises to lower right quadrant due to irritation of somatic nerves in the parietal peritoneum

42
Q

What is the cause of the pain shown in the diagram?

A

Small bowel colic

43
Q

What is the cause of the pain shown in the diagram?

A

Large bowel colic

44
Q

What is the cause of the pain shown in the diagram?

A

Renal/ureteric colic

45
Q

What is the cause of the pain shown in the diagram?

A

Uterine/Ovarian pain

46
Q

What is the cause of the pain shown in the diagram?

A

Bladder pain

47
Q

From what structure is the pain shown in the diagram?

Explain this and give three causes

A

Referred diaphragmatic pain

Explain:

Blood pooling in pelvis makes patient faint, liable to lie down

Blood runs up the abdomen to the diaphragm (C3/4/5 innervation) which corresponds to shoulder pain

Left shoulder only, liver prevents irritation of right hemidiaphragm

3 Causes:

Ruptured spleen

Ectopic pregnancy

Perforated Ulcer

48
Q

What is the major difference in the peritoneal cavities of men and women?

A

In men:

Completely closed to the exterior

In women:

Communication pathway to the exterior via the uterine tubes, cavity and vagina (potential pathway for infection)

49
Q

What structures secrete and absorb peritoneal fluid?

A

Secreted by the peritoneal epithelium (Simple squamous)

Absorbed by peritoneal lymphatic vessels (particularly on interior surface of diaphragm

50
Q

Describe the 2 reflections of the peritoneum

A

Parietal:

Lines the surrounding abdominal wall and structures

Served by same blood, lymph and (somatic) nerve supply as surrounding abd. wall (except central part of diaphragm)

Visceral:

Invests the viscera of the abdomen (Stomach, intestines etc)

Same blood, lymph and (visceral) nerve supply as underlying viscera

51
Q

What tissue directly underlies the parietal peritoneum and what is it’s significance?

A

Structure:

Extraperitoneal connective tissue

Significance:

Parietal peritoneum only attaches loosely to the adbominal wall via this tissue, allows for considerable expansion of bladder/rectum

Frequently contains a large amount of fat (Particulalry in obese males)

52
Q

What is mesentery?

A

A double layer of peritoneum that occurs as a result of invagination of the peritoneum

A continuity of the visceral and parietal pleura

Connects intraperitoneal structures to the body wall

53
Q

What are the Omenta?

(in general and specifics of each)

A

Omenta:

Double layered extension or fold of peritoneum that passes from the stomach and proximal duodenum to the adjacent organs in the abd. cavity

Greater:

Four layers

Hangs like an apron from the greater curve of the stomach

Attaches to the anterior surface of the transverse colon and its mesentery

Lesser:

Smaller double layered

Connects lesser curvature of stomach and the proximal part of the duodenum to the liver and stomach to portal triad

54
Q

What is a peritoneal ligament?

A

A double layer of peritoneum that connects an organ to another organ or the body wall

55
Q

What are the peritoneal ligaments that attach to the liver?

Where does each one also attach?

A

Falciform ligament

Anterior abd. wall

Hepatogastric ligament

Membranous portion of the lesser omentum

Stomach

Hepatoduodenal ligament

Thickened edge of the lesser omenta which conducts the portal triad

Duodenum

56
Q

What are the peritoneal ligaments that attach to the stomach?

A

Hepatogastric ligament

Gastrophrenic ligament

Gastrophrenic ligament

Gastrocolic ligament (Greater omentum)

57
Q

What are the functions of ‘Bare areas’ on organs?

A

Allow entry and exit of neurovascular structures

58
Q

How do we broadly classify structures associated with the peritoneum classified?

A

Infraperitoneal

Completely covered with peritoneum but not enclosed (Due to mesentery)

Retroperitoneal

Only partially covered by the parietal peritoneum

59
Q

What are the retroperitoneal structures?

A

Aorta and IVC

Oesophagus

Duodenum (Except for proximal part)

Most of the Pancreas

Ascending and descending colon + rectum

60
Q

Label the regions (in columns)

A

1st column:

Right Hypochondriac region

Right lumbar region

Right Iliac region

ASIS

2nd column:

Epigastric region

Umbilical region

Hypogastric/suprapubic region

3rd column:

Left hypochondriac region

Left Lumbar region

Left Iliac region

61
Q

What lines divide the 9 sections of the surface abdomen?

A

Divided Vertically by:

Midclavicular lines

Divided Horizontally by:

Subcostal line

Transtubecular line

62
Q

What is the transverse mesocolon and its significance?

A

Mesentery of the transverse colon

Significance:

Divides the peritoneal cavity into the supracolic and infracolic compartments

Supracolic:

Stomach, Liver, Spleen

Infracolic:

Small intestine and ascending + descending colon

Further divided into left and right by the small intestine mesentery

63
Q

What allows free communcation between supra and infracolic compartments of the peritoneal cavity?

A

Paracolic gutters lateral to ascending and descending colon

64
Q

What makes up the Greater sac?

A

Infra and supracolic compartments

65
Q

Describe the lesser sac

Hint: Sections, borders and function

A

Found behind the liver and stomach

Superior recess:

Posterior to liver

Bounded superiorly by the diaphragm and posterior layers of the liver’s coronary ligament

Inferior recess:

Behind the stomach

Bounded anteriorly by stomach and greater omentum

Bounded posteriorly by the pancreas, transverse mesocolon and the transverse colon

Function:

Allows free movement of the stomach on the structures posterior and inferior because its anterior and posterior walls slide smoothly over each other

66
Q

Describe the communication of the greater and lesser sacs

A

Epiploic foramen

Location:

Opening located posterior to the free edge of the lesser omentum (hepatoduodenal ligament)

Can be located by running a finger along the gall bladder to free the edge of the lesser omentum

67
Q

Label the boxes

What spaces are represented in red, blue and green?

A

Boxes, top to bottom:

Superior recess of the lesser sac

Lung

Lesser omentum

Falciform ligament

Subhepatic space

Pancreas

Duodenum

Transverse mesocolon

Transverse colon

Inferior recess of lesser sac

Mesentery of S. intestine

Greater omentum

Rectovesical pouch

Urinary bladder

Red:

Infracolic compartment

Blue:

Lesser sac (supracolic)

Green:

Greater sac (Supracolic)

68
Q

Label the black boxes clockwise from top left

Label the red box

A

Black:

Transverse colon

Supracolic compartment

Transverse mesocolon

Phrenicocolic lagament

Left colic flexure

Tenia coli

Root of S. Intestine mesentery

Descending colon

Left paracolic gutter

Left infracolic space

Right infracolic space

Right paracolic gutter

Ascending colon

Right colic flexure

Red:

Infracolic compartment

69
Q

What are the key features of the subphrenic spaces?

A

Right:

Lies between diaphragm superiorly and superior, anterior and lateral surfaces of the the right lob of the liver inferiorly

To the right of the falciform ligament

Common site for fluid collection post right sided abd. inflammation

Left:

Lies between the diaphragm superiorly and the left lob of the diaphragm inferiorly

To the left of the falciform ligament

Common site for fluid collection, particularly after a splenectomy

Substantially larger than the right space (Liver is on right)

70
Q

What is the recto-uterine pouch?

A

Small peritoneal reflection in females between the rectum and the posterior cervix and uterine fundus forming a small pouch

71
Q

What is the vesico-uterine pouch?

A

Shallow pouch in females between the anterior surface of the uterine fundus and the upper surface of the bladder

72
Q

What is the rectovesical pouch?

A

Shallow pouch found in males.

Formed where the peritoneum leaves the rectum at the junction of the middle and lower 1/3s then passes over the seminal vesicles and the superior aspect of the bladder

73
Q

Describe the mesentery of the small instestine

A

Broad, fan shaped fold

Connects ileum and jejunum to posterior abd. wall

Carries blood, lymph and nerves

Allows free movement of S.intestine

Root:

15cm from the duodenojejunal flexure on the left side at L2 to the ileocecal junction

74
Q

What is the sigmoid mesocolon?

A

Peritoneal fold attaching the sigmoid colon to the pelvic wall

75
Q

What are the chief sites of hernias?

Why these sites?

A

Inguinal Canal

Femoral Ring

Umbilicus

All sites of potential weakness

76
Q

Describe the inguinal canal, it’s contents and associations

A

Canal and associations:

Oblique passage extending downward and medial

From deep to superficial inguinal ring (~4cm)

Between muscles of anterior abdominal wall:

  • Transversalis apneurosis posterior
    • External oblique and Internal oblique (lateral 1/3 only) anteriorly*

Parallel and superior to inguinal ligament (**Floor)

Inferior to the medial crus of the external oblique apneurosis (**Roof)

Contents:

Spermatic cord in men

Round ligament in women

Ilioinguinal nerve in both sexes

77
Q

Label the black boxes from top center clockwise

A

Apneurosis of ext. oblique

Deep inguinal ring

Femoral vein

Superficial inguinal ring

Lacunar ligament

Pectineal ligament

Pectineus

Femoral canal

Femoral sheath

AIIS (anterior inferior iliac spine)

Femoral artery

Femoral nerve

Inguinal ligament

Iliopsoas

78
Q

Label the boxes top to bottom

A

Superfcal inguinal ring

Spermatic cord and ilioinguinal nerve

79
Q

What is an inguinal hernia?

A

A protrusion of the abdominal cavity contents throught the inguinal canal

Very common (Men 27%, Women 3% lifetime risk)

80
Q

Describe the two types of Inguinal hernia

A

Direct:

Protrudes into the inguinal canal through a weakened area in the transversalis fascia near the medial inguinal fossa within Hesselbach’s triangle

Indirect:

Protrudes through the deep inguinal ring within the diverging arms of the transversalis fascial sling

Result of failure of embryonic closure of the deep inguinal ring after the testicle has passed through it

81
Q

What are the borders of Hesselbach’s Triangle?

A

Inferior:

Medial half of the inguinal ligament

Medially:

Lower lateral border of the rectus abdominus

Laterally:

Inferior epigastric artery

82
Q

What is an epigastric hernia?

What are the primary risk factors?

A

Occur in the epigastric region

Between xiphoid process and Linea alba

Risk factors:

Obesity

Pregnancy

83
Q

What is an umbilical hernia?

Describe the two types

A

Occur throught the umbilical ring

Usually small

Congenital:

Result from increased intraabdominal pressure + Weakeness/incomplete closure of abd. wall post umbilical cord ligation at birth

Acquired:

Common in women and obese people

84
Q
A
85
Q

Where do femoral hernias occur?

How do they present clinically?

A

A protrusion of abd. viscera into the femoral canal through the femoral ring

Present as a small tender mass in the femoral triangle

86
Q

What is the effect of a femoral hernia on the surrounding tissues?

What structures are found laterally and medially of femoral hernias?

A

Compress contents of the femoral canal:

  • Loose connective tissue
  • Fat
  • Lymphatics

Lateral:

Femoral vein

Medial:

Lacunar ligament

87
Q

Describe briefly the differences in size of a femoral hernia that may occur

A

Initially:

Small, contained within canal

Later:

Canenlarge by passing through the saphenous opening into the subcutaneous tissue of the thigh

88
Q

In who are femoral hernias more common?

What is the major clinical complication? Why is this of particular concern in femoral hernias?

A

More common in women (Still less common than Inguinal hernias)

Strangulation:

Sharp, rigid boundaries of the femoral ring increase risk

89
Q

What are the two major complications of hernias?

A

Strangulation:

Constriction of blood vessels preventing flow of blood to hernia (Ischaemia/necrosis)

Incarceration:

Hernia cannot be reduced (pushed back into place) without very much external effort

90
Q

Label the boxes

A

Top left anticlockwise:

Inguinal ligament

Adductor longus

Sartorius

Femoral hernia

Saphenous opening

Great saphenous vein

Femoral hernia

Femoral sheath

Femoral ring

Intestine

91
Q

Label the boxes

A

Top right anticlockwise:

Epigastric hernia

Incisional hernia

Umbilical hernia

Indirect inguinal hernia

Direct inguinal hernia

Femoral hernia