Chapter 85: Diaphragmatic Hernias Flashcards
What are the three muscular components of the diaphragm?
How much of the diaphragm is composed of the central tendinous portion?
- Pars lumbaris (right and left crus) - attach to tendons on L3-4 near psoas minor
- Pars costalis
- Pars sternalis
Central tendinous portion approx 21% of surface area
Which crus is larger?
Right crus is significantly larger
Where do the splanchnic nerves and sympathetic trunk pass through the diaphragm?
Between the lateral portion of the crus and the 13th rib on each side
What are the three major opening of the diaphragm and what passes through each?
Caval foramen
- Caudal vena cava (adventitia fuses with central tendon with no extra space around cava)
Esophageal hiatus
- Esophagus and its blood supply
- Dorsal and ventral vagal trunks
Aortic hiatus
- Aorta
- Azygous and hemi-azygous veins
- Thoracic duct
What are the foramina of Morgagni?
The sternocostal triangles
Minor opening between the costal and sternal attachments of the diaphragm which allow the egress of the cranial epigastric arteries (termination of internal thoracic arteries)
Herniation through these openings is known as a retrosternal or Morgagni hernia
What is the major source of lymphatic drainage from the peritoneal cavity?
Stomata within the diaphragmatic peritoneum
Drains to sternal LNs
Where do the phrenic nerves arise?
- Dogs: 5th, 6th and 7th cervical nerves
- Cats: 4th, 5th and 6th cervical nerves
What is reexpansion pulmonary edema?
An inflammatroy response to lung expansion that causes increased capillary permeability
Presumable due to expansion-related mechanical injury to alveolar capillary membrane and reperfusion injury
How can intra-abdominal pressure be measured?
What is considered normal?
Can be measures with an indwelling urinary catheter
- IAP 5-10 mmHg - monitored and adequately hydrated
- 11-20 mmHg - Medical treatments instituted
- Over 20 - Surgical decompression
What are the medical and surgical options for abdominal compartment syndrome?
Medical
- Analgesics
- Evacuation of intraperitoneal contents (fluid/air)
- Evaculation of intraluminal contents (urine, gastric air)
Surgical
- Surgical mesh
- Removal of spleen
- Advancement of diaphragm
- Relaxing incisions in external rectus sheath
- Leave linea unapposed
What is the blood supply to the diaphragm?
phrenic arteries from the phrenicoabdominal artery
Innervation to the diaphragm is what nerve?
Phrenic nerve
From 5, 6, 7 spinal nerves in dogs “ 5,6,7 all dogs go to heaven”
