Abdominal Wall Flashcards
Describe the two peritoneum
Peritoneum is a serous membrane that lines the abdominopelvic cavity and invests visceral organs
Visceral peritoneum: area of membrane that touches the visceral organs
Parietal peritoneum: area of membrane that lines the abdominal walls
What is the peritoneal cavity?
The space between the visceral and parietal membrane that contains only enough extracellular fluid to lubricate the membranes
What is present in the Right upper quadrant? (RUQ)
Liver: right lobe
gallbladder
stomach: pylorus
Duodenum: parts 1-3
Pancreas: Head
Right suprarenal gland
Right kidney
Right colic (hepatic) flexure
Ascending colon: superior part
Transverse colon: Right half
What is present in the Left Upper Quadrant? (LUQ)
Liver: left lobe
spleen
stomach
jejunum and proximal ileum
Pancreas: body and tail
left kidney
left suprarenal gland
left colic (splenic) flexure
Transverse colon: Left half
descending colon: superior part
What is present in the Right Lower Quadrant? (RLQ)
Cecum
appendix
most of ileum
ascending colon: inferior part
right ovary
right uterine tube
right ureter: abdominal part
right spermatic cord: abdominal part
uterus (if enlarged)
urinary bladder (if very full)
What is present in the Left Lower Quadrant? (LLQ)
sigmoid colon
descending colon: inferior part
left ovary
left uterine tube
left ureter: abdominal part
left spermatic cord: abdominal part
Uterus (if enlarged)
urinary bladder (if very full)
What special function does the Linea Alba serve?
Runs from xiphoid process to pubic symphysis
Allows small vessels and nerves to pass to the skin
Has umbilical ring where blood vessels used to run to the placenta
What special function does the Umbilicus serve/used to serve?
All layers at abdominal wall fuse at the umbilicus
Used to be the site of the umbilical cord for nutrients while in the womb
Where does the neurovascular plane live in the anterolateral abdominal wall?
Between the internal oblique and Transverse abdominis
What lives in the neurovascular plane in the anterolateral abdominal wall?
Nerves and blood vessels that supply the anterolateral wall of the abdominal cavity
Where do most of the nerves and blood vessels supplying the anterior part of the abdominal wall live?
They leave the neurovascular plane and lie in the subcutaneous tissue
How is the layout of the neurovascular plane in the anterolateral abdominal wall similar to that of the thoracic wall?
Layout is similar to how the intercostal spaces are in the thoracic cage
Nerves and blood vessels are present in intercostal spaces the same as the neurovascular plane
What other actions can the abdominal muscles do individually or combined?
Increase intra-abdominal pressure resulting in:
forced expiration
defecation
micturition (urination)
vomiting
child birth
heavy lifting
Trunk movements/pelvis tilting
What is the difference between a Dermatome and a peripheral nerve?
Dermatome: carried by a spinal nerve in a segmental distribution to supply an area of skin
Peripheral: fibers carried usually by a plexus and have specific names
What are the sensory nerves of the anterolateral abdominal wall?
Thoraco-abdominal nerves (T7-T11)
Subcostal nerve (T12)
L1 splits into two named nerves
- iliohypogastric
- ilio-Inguinal
Describe the Thoraco-abdominal nerves (T7-T11) and what they supply (dermatomes)
Continuation of intercostal nerves
Anterior/lateral cutaneous branches
- T9 above umbilicus
-T10 around umbilicus
What does the Subcostal nerve ( T12) supply?
supplies skin inferior to the umbilicus
Where does the iliohypogastric nerve supply?
supplies skin over iliac crest and hypogastric regions
Also the Internal oblique and Transverse abdominis
Where does the ilio-inguinal nerve supply?
supplies skin of inguinal region, external perineum, and adjacent thigh
Also the Internal oblique and Transverse abdominis
Pathway of a sensory nerve from the spinal cord to the skin
From ventral ramus -> neurovascular plane -> branch off to either lateral cutaneous branch or anterior cutaneous branch -> skin of those two regions
How is the arterial supply to the anterolateral abdominal wall similar to the nerve supply?
The arteries follow the same path as the nerves in the neurovascular plane and distribution follows the muscles
How are the vessels different when it comes to the anterolateral vessels compared to the anterior vessels?
Anterolateral vessels seem to flow more in a circumferential pattern (wrap around)
Anterior vessels seem to flow more in a vertical patter in rectus sheath
Describe the pathway of an Inguinal Hernia
Pass through the inguinal canal into the scrotum in males and the labia majus in females
What is the most common inguinal hernia?
indirect inguinal hernias
List the contents of the spermatic cord
Ductus Deferens (Vas Deferens)
Arteries
venous plexus
lymphatic vessels
sympathetic nerves to arteries and ductus deferens
genital branch of genitofemoral nerve
Clinical significance of the internal oblique and transverse abdominis muscles attaching to the throacolumbar fascia
Lumbar stabilization
when contracted, they pull bilaterally on the transverse processes which help to lift and stabilize the lumbar vertebrae
Describe the difference between the two layers of peritoneum
Parietal peritoneum - lines internal wall
sensitive to pressure, pain, heat, cold, and laceration
well localized pain
Visceral peritoneum - lines organs
insensitive to pain BUT sensitve to stretching and chemical irritation
Pain referred to dermatomes (spinal ganglia)
Intraperitoneal
completely covered with visceral peritoneum
similar to how lungs are
Extraperitoneal
completely outside peritoneum
Retroperitoneal
partially covered/outside
EX: kidneys
Subperitoneal
under peritoneum
urinary bladder only touches parietal peritoneum superiorly
What is a hernia?
Bulging of tissue through an abnormal hole or opening
usually occurs through fossae
Mesentary
-double layer of peritoneum
-surrounds organs and connects to the body wall
-usually named for organs they surround
-provides a pathway for neurovascular structures to communicate between organ and body wall
Omentum
-double layer of peritoneum
-from stomach and duodenum to organs
What are the two parts of the omentum?
Greater omentum - 4 layers and hangs like an apron from stomach and duodenum
Lesser omentum - 2 layers that connect stomach and duodenum to the liver
Peritoneal ligament
-double layer of peritoneum
-attaches an organ to the abdominal wall OR an organ to another organ
What passes through the Caval opening?
Inferior vena cava
Right phrenic nerve
Lymphatic vessels going to the liver
What happens to the Caval opening when the diaphragm contracts?
This widens the opening, dilating the IVC for greater blood flow to the heart
What passes through the Esophageal Hiatus?
Esophagus
Vagal trunk
Gastric vessels
Lymphatic vessels
What does the right crus do when crossing the Esophageal Hiatus?
This forms a sphincter around the esophagus when the diaphragm contracts constricting the Hiatus
What passes through the Aortic Hiatus?
Descending aorta
Thoracic duct
Azygos & Hemi-azygos veins
What passes through the Medial Arcuate Ligament?
Psoas major
What passes through the Lateral Arcuate Ligament?
Quadratus Lumborum (QL)
What arteries are unpaired Visceral branches from the abdominal aorta?
Celiac artery
superior and inferior mesentaric arteries
What arteries are paired visceral branches of the abdominal aorta?
Suprarenal arteries
Renal arteries
Gonadal arteries
What arteries are paired parietal branches of the abdominal aorta?
Phrenic arteries
subcostal arteries
lumbar arteries
What artery is unpaired parietal branch of the abdominal aorta?
Median sacral artery
What veins drain into the IVC from the abdominopelvic region?
Hepatic portal vein
Right suprarenal vein
Right/left renal vein
Right gonadal vein
Right/left common iliac vein
Right/left inferior phrenic vein
What is special about the left renal vein?
Multiple veins branch off of it including:
-left suprarenal vein
-left gonadal vein
Flow of lymph from the abdominopelvic region to the venous system
Internal/External iliac lymph nodes -> Common iliac nodes -> pre-aortic lymph nodes -> intestinal lymphatic trunks -> intestinal lymphatic trunks + lumbar lymphatic trunks + thoracic lymphatic trunks -> cisterna chyli -> Thoracic duct -> left subclavian + internal jugular -> left venous angle
What is a Hiatal Hernia?
This protrudes into the thorax through the esophageal Hiatus
Types of Hiatal Hernias?
Para-esophageal
Sliding
What is a para-esophageal hernia?
-less common
-through the fundus and pouch of peritoneum
-usually no regurgitation because cardia of stomach stays in place
What is a sliding hernia?
-more common
-abdominal esophagus, cardia, and fundus slide superiorly through hiatus when lying down/bending over
-Regurgitation is possible due to right crus being weak
What are abdominal Hernias?
structure pierces through abdominal wall tissue
What is an Epigastric Hernia?
-protrudes through linea alba
-usually fat lobules in hernia
-painful if nerve is compressed
What is an Umbilical Hernia?
-weakness from incomplete closure of umbilical ring
-common in neonates
-mostly common in women and obese
What is an Inguinal Hernia?
A hernia that passes through/around the inguinal canal
What gender usually has more inguinal hernias?
Males
What is a Direct Inguinal Hernia?
-passes through or around inguinal canal
-medial portion of inguinal canal
-lateral to spermatic cord
-RARELY enter the scrotum
-palpable at the superficial inguinal ring
What is an Indirect Inguinal Hernia?
-more common
-Transverses entire inguinal canal
-inside the spermatic cord
-enter the scrotum (or labia majus)
-palpable at superficial & deep inguinal rings
What are the two Gridiron incisions?
McBurney
Suprapubic
What is a McBurney incision?
-muscle splitting
-usually for appendix surgery
-2.5cm superomedial to ASIS
-spares muscles of the anterolateral abdominal wall
What is a Suprapubic incision?
-“bikini” incision
-C-Sections
-Horizontal incision
-spares the Rectus abdominis muscle
What is Peritonitis?
-inflammation of peritoneum
-usually from bacterial contamination from surgery or a traumatic penetration or rupture
-symptoms: pain in overlying skin, increased muscle tone, and tenderness, fever, and constipation
What is General Peritonitis?
-widespread peritonitis in the peritoneal cavity
-dangerous and lethal because peritoneal surfaces absorb material RAPIDLY
What is Ascites?
-excess fluid in peritoneal cavity
-distended abdomen
-usually from mechanical damage (internal bleeding) or portal hypertension, starvation, or metastasis of cancer cells
What are Peritoneal Adhesions?
-scar tissue
-becomes sticky from fibrin (usually associated with damage to peritoneum)
-limits visceral movement
-forms between visceral peritoneum and organs AND between visceral and parietal peritoneum
What are hiccups?
-involuntary spasms of diaphragm
-sudden inhalation
-sound is from the epiglottis closing
-usually from indigestion, diaphragm irritation, alcoholism
Where is diaphragmatic pain referred to?
-Phrenic nerve (C3-C5) is usually to the shoulder region
-Inferior intercostal nerves is usually referred to the costal margins
What is an abdominal aortic aneurysm (AAA)?
-abnormal and excessive dilation or ballooning of abdominal aorta
-usually congenital or weakness in aortic wall causes this
-90% fatal if ruptured
-will be severe back or abdominal pain
