3.3.2. ANATOMY LAB Pertinent Embryo/Celiac Portal Circulation

Question 1

What is the peritoneal cavity and what are its divisions

Answer 1

The peritoneal cavity is a potential space between the parietal peritoneum and visceral peritoneum, that is, the two membranes that separate the organs in the abdominal cavity from the abdominal wall.

Question 2

What is the abdominopelvic cavity

Answer 2

The abdominopelvic cavity is a body cavity that consists of the abdominal cavity and the pelvic cavity. It contains the stomach, liver,pancreas, spleen, gallbladder, kidneys, and most of the small and large intestines. It also contains the urinary bladder and internal reproductive organs.

Question 3

Parietal peritoneum

Answer 3

parietal peritoneum - The outer layer, called the parietal peritoneum, is attached to the abdominal wall and the pelvic walls

Question 4

Visceral peritoneum

Answer 4

visceral peritoneum - The inner layer, the visceral peritoneum, is wrapped around the internal organs that are located inside the intraperitoneal space. It is thinner than the parietal peritoneum.

Question 5

Intraperitoneal organs

Answer 5

Intraperitoneal organs include the stomach, the first 5 centimeters and the fourth part of the duodenum, jejunum, ileum, cecum, appendix, transverse colon, sigmoid colon, and the upper third of the rectum, as well as, the liver, spleen, and the tail pancreas

Question 6

Retroperitoneal organs

Answer 6

Retro - SAD PUCKER - Suprarenal (adrenal) gland, aorta/IVC, duodenum (2nd and 3rd part), pancreas, ureters, colon (ascending and descending), kidneys, esophagus, rectum

Question 7

Peritoneal fluid? What is the most common problem with it?

Answer 7

peritoneal fluid components and volume - Peritoneal fluid is a liquid that is made in the abdominal cavity to lubricate the surface of the tissue that lines the abdominal wall and pelvic cavity and covers most of the organs in the abdomen. An increased volume of peritoneal fluid is called ascites

Question 8

Discuss what we mean by peritoneal folds/reflections.

What are the important ones?

Answer 8

peritoneal fold (reflection) - Where the peritoneum changes direction

1. The peritoneal reflection to the jejunum and ileum is termed the mesentery
2. those to the colon are each known as a mesocolon.
3. Some reflections are termed ligaments or folds, e.g., gastrohepatic ligament or rectouterine fold. Most such ligaments contain blood vessels, and most folds are raised by underlying vessels in their free edges.
4. A broad peritoneal sheet or reflection is termed an omentum (the Greek word for which is epiploon)

Question 9

What are the left and right subphrenic recesses? What divides them?

Answer 9

right and left subphrenic recesses - the recesses in the peritoneal cavity between the anterior part of the liver and the diaphragm, separated into right and left by the falciform ligament

Question 10

Hepatorenal recess: Discuss its importance and its alternative name.

What can go wrong here?

Answer 10

hepatorenal recess (Morison’s Pouch) - the space that separates the liver from the right kidney. As a potential space, the recess is not filled with fluid under normal conditions. However, fluid can collect in this space in circumstances where the abdomen fills with fluid, such as hemoperitoneum

Question 11

Where are the right and left paracolic gutters?

Answer 11

right and left paracolic gutters - The paracolic gutters (paracolic sulci,paracolic recesses) are spaces between the colon and the abdominal wall

Question 12

What is the mesentery? What’s in it?

Answer 12

mesentery (mesogastrium, mesocolon, mesoappendix) - The mesentery is a fold of membranous tissue that arises from the posterior wall of the peritoneal cavity and attaches to the intestinal tract. Within it are the arteries and veins that supply the intestine.

Question 13

Rectovesical pouch

Answer 13

Between the rectum and the bladder the peritoneal cavity forms, in the male, a pouch, the rectovesical excavation (‘rectovesical pouch)

Question 14

Vesicouterine excavation

Answer 14

In human female anatomy, the vesicouterine excavation (or uterovesical pouch of Meiring) is a second, but shallower, pouch formed from the peritoneum over the uterus and bladder, continued over the intestinal surface and fundus of the uterus onto its vesical surface, which it covers as far as the junction of the body and cervix uteri, and then to the bladder.

You know…to be brief…

Question 15

What are the gravity dependent recesses and what are we worried about with them?

Answer 15

Gravity dependent recesses of the abdominopelvic peritoneal cavity - See the two discussed directly above. Vesicouterine pouch and the rectouterine pouch are important because they are gravity dependent recesses. Pus may drain there in infection.

Question 16

What are potential spaces and what do we use them for?

Answer 16

Potential Spaces - “Potential spaces” are locations where two anatomical layers can be separated easily – either by easy finger dissection or by a collection of blood, pus, or other fluid). They form excellent route for the surgeon to dissect in a bloodless field in order to expose the target of the operation

Question 17

Where is the retropubic space and what do we also call it?

Answer 17

Retropubic space - (Space of Retzius)

Retropubic space is the extraperitoneal space between the pubic symphysis and urinary bladder

Question 18

Is the retropubic space a space in the abdominopelvic cavity? What do we use this space for medically?

Answer 18

This space is NOT in the abdominopelvic cavity, but is a “potential space” that can be finger dissected to gain quick access to the bladder without entering the abdominopelvic cavity. You may use it to place an in-dwelling catheter to drain the bladder if the patient’s urethra is disrupted or obstructed

Question 19

What is the retrorectal space and why is it important for surgery?

Answer 19

area of loose connective tissue between the rectum anteriorly and the sacrum and upper coccyx posteriorly.

This is another potential space that is not in the abdominopelvic cavity but that is easily dissected in order to surgically mobilize the rectum for its removal (e.g., for a distal rectal cancer)

Question 20

Where are the greater and lesser omenta?

Question 21

Where and what is the greater sac?

Answer 21

First of all, phrasing.

2nd,

greater sac - In human anatomy, the greater sac, also known as the general cavity (of the abdomen) or peritoneum of the peritoneal cavity proper, is the cavity in the abdomen that is inside the peritoneum but outside of the lesser sac

Question 22

What and where is the lesser sac?

Answer 22

lesser sac - The omental bursa, also known as the lesser sac, is the cavity in the abdomen that is formed by the lesser and greater omentum

Question 23

What and where is the omentum foramen?

Answer 23

omentum foramen - In human anatomy, the omental foramen(epiploic foramen, foramen of Winslow, or uncommonly aditus; Latin: Foramen epiploicum), is the passage of communication, or foramen, between the greater sac (general cavity (of the abdomen)), and the lesser sac.

Question 25

What is the hepatoduodenal ligament and what is the portal triad?

Answer 25

hepatoduodenal ligament - Part of the lesser omentum and contains the portal triad

portal triad - common bile duct, portal vein, proper hepatic artery

Question 26

Describe the hepatogastric ligament

Answer 26

hepatogastric (gastrohepatic) ligament - part of the lesser omentum

The cranial part of the lesser omentum (omentum minus) is formed by the hepatogastric ligament (ligamentum hepatogastricum), extending between the liver and stomach

Question 27

Discuss the splenorenal ligament.

Answer 27

The splenorenal ligament (or lienorenal ligament), is derived from the peritoneum, where the wall of the general peritoneal cavity comes into contact with the omental bursa between the left kidney and the spleen; the lienal vessels (splenic artery and vein) pass between its two layers. It contains the tail of the pancreas, the only intraperitoneal portion of the pancreas, and splenic vessels

Question 28

Discuss the coronary ligament

Answer 28

coronary ligament - The coronary ligament of the liver refers to parts of the peritoneal reflections that hold the liver to the inferior surface of the diaphragm.

Question 29

Discuss the right triangular ligament

Answer 29

The right triangular ligament is situated at the right extremity of the bare area, and is a small fold which passes to the diaphragm, being formed by the apposition of the upper and lower layers of the coronary ligament.

Question 30

Discuss the left triangular ligament

Answer 30

The left triangular ligament is a fold of some considerable size, which connects the posterior part of the upper surface of the left lobe of the liver to the diaphragm; its anterior layer is continuous with the left layer of the falciform ligament.

Question 32

What is the bare area of the liver?

Answer 32

bare area of the liver - “bare” meaning that is against the diaphragm and is not coated with visceral peritoneum

Question 33

The stomach rises as a dilation, the dorsal portion of which grows faster than the ventral portion, and this dorsal portion becomes the greater curvature. It rotates 90 degrees around its longitudinal axis so that its original left wall becomes anterior, and its original right side becomes posterior (“LARP”- “Left Anterior, Right Posterior”). You can use your left hand to demonstrate this:

Answer 33

Before rotation: Place your left hand, with the digits straight, over your umbilicus with the thumb forward and the digits all pointing downward toward your feet.

Rotation: Keep the hand over your umbilicus, but rotate and swing your hand and forearm so that your thumb is now pointing upward and your fingers are now pointing to the right.

This is how the stomach rotates due to its differential rates of growth. It also explains the innervation of the anterior aspect of the stomach by the left vagus nerve and the posterior aspect by the right vagus nerve, since the rotation carries these nerves with the stomach as it rotates.

Question 34

What is the esophagogastric junction also called?

Answer 34

Z line

Question 35

Discuss the trunks of the vagus nerve

Answer 35

The anterior vagal trunk is a branch of the vagus nerve which contributes to the esophageal plexus. It consists primarily of fibers from the left vagus, but also contains a few fibers from the right vagus nerve.

The posterior vagal trunk is a branch of the vagus nerve which contributes to the esophageal plexus. It consists primarily of fibers from the right vagus, but also contains a few fibers from the left vagus

Question 36

What is the cardiac orifice and what is it also called?

Answer 36

Cardial (cardiac) orifice - the trumpet-shaped opening of the esophagus into the stomach.

Question 37

What is the cardiac notch?

Question 38

Where is the angular incisure?

Question 39

Where are the lesser and greater curvatures, the body, and the fundus?

Question 40

What does pylorus mean?

Where are the pyloric antrum and canal, and pyloric orifice?

Answer 40

greek for gatekeeper

Question 41

What are gastric rugae?

Answer 41

gastric rugae - folds in the tissue that allow the stomach to expand…I’m looking at you Kate.

Question 42

What is a sliding hiatal hernia?

Answer 42

In a sliding hiatal hernia, the stomach and the section of the esophagus that joins the stomach slide up into the chest through the hiatus. This is the more common type of hernia

Question 43

What is the paraesophageal hernia?

Answer 43

The paraesophageal hernia is less common, but is more cause for concern. The esophagus and stomach stay in their normal locations, but part of the stomach squeezes through the hiatus, landing it next to the esophagus. Although you can have this type of hernia without any symptoms, the danger is that the stomach can become “strangled,” or have its blood supply shut off.

Question 44

Discuss congenital hypertrophic pyloric stenosis. How do we treat it and how does it present?

Answer 44

Congenital hypertrophic pyloric stenosis (also called pyloric stenosis) can cause inability of an infant to feed, with the baby vomiting immediately after taking formula.

Characteristically, the emesis (vomit contents) is “clear” and contains no (greenish colored) bile – since nothing that is eaten can get past the blocked pylorus and thus there is no “reflux” of bile-stained liquids from the duodenum retrograde into the stomach.

Fortunately, this is easily corrected by surgery: cutting through the thick muscle to release the stenosis.

Question 45

Discuss the parts of the duodenum

Question 46

Where is the ligament of treitz and why is it important?

Answer 46

Ligament of Treitz - the suspensory muscle of the duodenum.

The ligament of Treitz is actually formed by slips of muscle from the diaphragm and from the duodenum. It facilitates peristalsis and holds the important duodenojejunal junction in position – thus preventing abnormal twisting of the bowel (which could be fatal).

Question 47

Why do surgeons like the ligament of treitz?

Question 48

What is a paraduodenal hernia?

Answer 48

Paraduodenal hernia - Paraduodenal hernias are a type of internal hernia whereby an abdominal organ passes through a defect into another compartment within the abdominal cavity

Question 51

What is an annular pancreas

Answer 51

Annular pancreas is a rare condition in which the second part of the duodenum is surrounded by a ring of pancreatic tissue continuous with the head of the pancreas.

Question 52

What is a pancreatic pseudocyst?

Answer 52

A pancreatic pseudocyst is a circumscribed collection of fluid rich in pancreatic enzymes,blood, and necrotic tissue, typically located in the lesser sac of the abdomen

Question 53

When do we see pancreatic pseudocysts and what should we do and why?

Answer 53

Such a cyst is serious and must be drained (usually into the stomach) to avoid activation of the powerful pancreatic enzymes in the fluid that could digest the retroperitoneal tissues and vessels (a fatal condition). Such a cyst is sometimes seen after a stab wound or GSW (gunshot wound) that penetrates through the stomach and injures the pancreas (which is right “behind” the stomach)

Question 54

Why do many pancreatic cancers cause jaundice?

Answer 54

Jaundice is a yellowing of the skin and eyes caused by excess bilirubin (a component of bile) in the blood. A tumor in the head of the pancreas can cause narrowing of the bile duct and block the bile flowing from the gallbladder into the small intestine

Question 55

Why do pancreatic cancers cause severe pain

Answer 55

Cancers that start in the body or tail of the pancreas can grow fairly large and start to press on other nearby organs, causing pain. The cancer may also spread to the nerves surrounding the pancreas, which often causes back pain.

Question 56

In a car accident, why do we worry about the pancreas?

Answer 56

Pancreas in a car accident - Note that the pancreas lies “draped” over the vertebral column and can “break in half” in an auto accident if the patient sustains a strong blow to the anterior abdominal wall (such as with a steering wheel injury or a seatbelt compression injury). If this occurs, pancreatic juice can leak out, become activated, and begin to digest the patient’s own tissues

Question 57

Rule about pancreas when it comes to surgeries:

Answer 57

How the pancreas relates to your entire life - the pancreas is a very important organ that doesn’t take well to manipulation or injury. Surgery residents often warn new interns and med students of the three main rules that they need to follow in order to succeed on the surgery rotation: “Eat when you can. Sleep when you can. And DON’T fool* with the pancreas!” *Unfortunately, other words are often substituted for “fool”

Question 59

Division of the liver into right and left sides by what?

Question 60

What is so important surgically about the divisions of the liver?

Answer 60

The major blood vessels and bile ducts follow these major lobar divisions - as well as the subdivisions.This anatomical feature has important advantages when, as a surgeon, you are trying to control hemorrhage from a liver wound or if you are removing segments of the liver (e.g., for cancer, trauma, infection, congenital aberrations, etc.)

Question 61

Describe blood flow through the liver. (Long card, but once you know it, you can describe it quickly enough)

Answer 61

The liver gets a dual blood supply from the hepatic portal vein and hepatic arteries. Supplying approximately 75% of the liver’s blood supply, the hepatic portal vein carries venous blood drained from the spleen, gastrointestinal tract, and its associated organs. The hepatic arteries supply arterial blood to the liver, accounting for the remainder of its blood flow. Oxygen is provided from both sources; approximately half of the liver’s oxygen demand is met by the hepatic portal vein, and half is met by the hepatic arteries.

Blood flows through the liver sinusoids and empties into the central vein of each lobule. The central veins coalesce into hepatic veins, which leave the liver.

Question 62

What is hepatomegaly?

Answer 62

Hepatomegaly - Hepatomegaly is swelling of the liver beyond its normal size. If both the liver and spleen are enlarged, it is called hepatosplenomegaly.

Question 64

What is cirrhosis?

Answer 64

Cirrhosis - Cirrhosis is scarring of the liver and poor liver function. It is the final phase of chronic liver disease.

Question 65

Discuss Portal Hypertension and Varices

Answer 65

Portal Hypertension and Varices - If the vessels in the liver are blocked due to liver damage, blood cannot flow properly through the liver. As a result, high pressure in the portal system develops. This increased pressure in the portal vein may lead to the development of large, swollen veins (varices) within the esophagus, stomach, rectum, or umbilical area (belly button). Varices can rupture and bleed

Question 66

What is caput medusae?

Answer 66

Caput Medusae - Caput medusae, also known as palm tree sign, is the appearance of distended and engorged paraumbilical veins, which are seen radiating from the umbilicus across the abdomen to join systemic veins

Question 69

Spiral valve within the cystic duct?

Answer 69

spiral fold (valve) within the cystic duct - Spiral valves of Heister are undulating folds or valves in the proximal mucosa of the cystic duct. The cystic duct attaches the gallbladder to the common bile duct.

Question 70

What is the importance of the cystic artery?

Answer 70

cystic artery - The cystic artery supplies oxygenated blood to the gallbladder and cystic duct.

Question 71

How does the common bile duct relate to cancer and jaundice?

Answer 71

Clinical Note - If the common bile duct becomes anatomically obstructed (by a gallstone or a pancreatic cancer), it is life threatening. Jaundice is an important symptom and its etiology (its cause) is often life-threatening. Note that the common bile duct (CBD) passes right through the pancreas. Thus cancer of the head of the pancreas often obstructs the CBD and causes jaundice. It can also obstruct the portal vein and superior mesenteric vein. This can make the cancer inoperable

Question 72

What is a Meckel’s diverticulum?

Answer 72

A Meckel’s diverticulum is a pouch on the wall of the lower part of the intestine that is present at birth (congenital). The diverticulum may contain tissue that is the same as tissue of the stomach or pancreas.

Question 73

What are arterial arcades?

Answer 73

The arterial arcades (intermesenteric arterial anastomoses or Riolan arcades[1]) are loops of arteries around the jejunum and ileum.

Question 74

What are vasa recta?

Answer 74

Nearest the duodenum, the vasa recta are long and regular in distribution, and the translucent spaces (lunettes) are extensive. Vasa recta are straight arteries coming off from arcades in the mesentery of the jejunum and ileum, and heading toward the intestines.

Question 75

What are circular folds?

Answer 75

The circular folds (valves of Kerckring) (also, plicae circulares / valvulae conniventes) are large valvular flaps projecting into the lumen of the small intestine.

Question 76

What is an ileus?

Answer 76

“Sympathetic stimulation reduces peristaltic and secretory activity of the intestine…” This reduction in secretory and peristaltic activity is called an ileus – and it occurs any time there is an inflammation or disturbance of the peritoneal cavity (for example, when a surgeon operates on a structure inside the peritoneal cavity)

Question 77

What can cause an ileus?

Answer 77

Merely opening the peritoneal cavity can cause an ileus. Unfortunately, it can last for days on end and can be life-threatening – depending on how severe the disturbance is to the peritoneal cavity or bowel

Question 78

Discuss the bowel in terms of what causes it to hurt and what will not hurt it

Answer 78

note that the bowel is insensitive to cutting or burning (e.g., in surgery: cutting through the bowel wall or burning a bleeding vessel on the bowel wall with electrocautery) – but it is exquisitely sensitive to distention! That’s why gas pains can be so painful – but cutting or stabbing the bowel is not! However, after a stab wound, the bowel leaks – and that IS painful, since it causes peritonitis

Question 80

What is the root of the mesentery?

Question 81

Discuss the blood flow of the mesentery?

Answer 81

the blood supply to the entire small bowel and proximal half of the colon is from the Superior Mesenteric Artery (SMA) and its branches. The SMA runs within the leaves of peritoneum that comprise this “root of the mesentery”

Question 82

What is somatic pain?

Answer 82

Somatic pain comes from the skin and deep tissues, while visceral pain comes from the internal organs. Somatic pain is generally described as musculoskeletal pain. Because many nerves supply the muscles, bones and other soft tissues, somatic pain is usually easier to locate than visceral pain.

Question 83

Discuss visceral pain?

Answer 83

Visceral pain is internal pain. It comes from the organs or the blood vessels, which are not as extensively innervated, or supplied by, sensory nerves. Unlike somatic pain, visceral pain may feel dull and vague, and may be harder to pinpoint.

Question 85

What do we worry about in the transverse mesocolon during surgery?

Answer 85

The transverse mesocolon contains the middle colic artery, which is vulnerable to injury when one is moving the mesocolon out of the way in order to get to other intra-abdominal organs – especially when mobilizing the omentum from the colon. If this artery is injured, the transverse colon can become ischemic (starved of blood) and could necrose (die).

Question 87

What is a colonic volvulus?

Answer 87

The term volvulus is derived from the Latin word volvere (“to twist”). A colonic volvulus occurs when a part of the colon twists on its mesentery, resulting in acute, subacute, or chronic colonic obstruction. The main types of colonic volvulus are sigmoid volvulus and cecal volvulus

Question 89

What is a laparotomy?

Question 90

Peritonitis?

Answer 90

peritonitis - Peritonitis is an inflammation (irritation) of the peritoneum, the thin tissue that lines the inner wall of the abdomen and covers most of the abdominal organs

Question 91

What are peritoneal adhesions?

Answer 91

peritoneal adhesions - Adhesions are fibrous bands that form between tissues and organs, often as a result of injury during surgery. They may be thought of as internal scar tissue that connects tissues not normally connected

Question 92

What is abdominal paracentesis?

Answer 92

abdominal paracentesis - Paracentesis is a procedure to take out fluid that has collected in the belly (peritoneal fluid).

Question 93

What is carcinoma of the stomach?

Answer 93

Carcinoma of the stomach - Stomach cancer, also called gastric cancer, is a malignant tumor arising from the lining of the stomach

Question 94

Distinguish between gastric, peptic, and duodenal ulcers?

Answer 94

gastric ulcers - When the ulcer is in the stomach, it is called a gastric ulcer.

peptic ulcers - An ulcer in the lining of the stomach or duodenum is referred to as a peptic ulcer

duodenal ulcers - When the ulcer is in the duodenum, it is called a duodenal ulcer

Question 95

Fecalith

Answer 95

Fecalith: A hard stony mass of feces in the intestinal tract. A fecalithcan obstruct the appendix, leading to appendicitis. Fecaliths can also obstruct diverticuli. Also known as coprolith and stercolith.

Question 96

Diverticulosis

Answer 96

diverticulosis - presence of diverticuli, or pouches, in the large intestine. Can cause pain and irritation if it progresses to diverticulitis

Question 97

What are the three segments of the gut and what supplies them from the aorta?

Answer 97

The gut consists of three segments, each of which has an unpaired visceral branch of the aorta to provide its blood supply

Foregut (caudal) - Celiac artery (Celiac Trunk)

Midgut - Superior Mesenteric artery

Hindgut - Inferior Mesenteric Artery