guided study pre msa Flashcards
what is the diapghram responsible for?
inspiration at rest
describe the embrylogy of the diapghram
- develops in the neck mainly from the septum transversum close to the thoracic inlet
- nerve supply C3,4,5 (phrenic nerve)
- as the lungs expand during development the diapghram is forced inferiorly through the thoracic cage dragging the nerve supply with it.
what are the 4 sources of origin of the diapghram?
1- septum transversum
2- 2 pleuro-peritoneal folds of membrane that fuse with the septum transversum
3- the oesophagus and its mesentery in the midline dorsally
4- the ingrowth from the body wall.
what are the attachments of the diapghram?
- xiphoid process
- the costal margin
- ribs 11 and 12
- posteriorly the lateral and medial arcuate ligament
they all converge onto the central tendon.
where does the right and left crura arise up to?
where does the median arcuate ligament lie?
left = L1 Aand L2
right = L1, L2 and L3
T12
what is the inferior surface of the diapghram lined with?
inferior = peritoneum (apart from the ‘bare area’ that is posterior to the liver)
how is the subphrenic intraperitoneal space made?
on the superior surface of the liver the peritoem reflects onto the diapghram to create the subphrenic intraperitoneal space where fluids can collect in the abdomen
what are the 3 opening of the diapghram and what passes through each space?
T8= right phrenic nerve and inferior vena cava
T10 = oesophagus, anterior and posterior vagal trunks, left gastric vein and oesophageal branch of the left gastric artery
T12= thoracic duct, axygos and hemiazygous, descending thoracic aorta
what is a hiatus hernia?
a condition where a small part of the stomach herniates through the diaphram into the thorax
what is the differance between a sliding and a rolling hernia?
sliding = the cardia (the normally intra-abdominal part of the gastro-oesophageal junction has managed to get above the diapghragmatic oesophageal hiatus) is now above the constrictors allowing acid to be secreted into the lower esophagus.
rolling = part of the fundus of the stomach has herniated through the diapghram but the gastro oesophageal junction is still intact (this is not the case for sliding)
what is the different symtpoms for rolling and sliding hernia?
sliding:
- severe heart burn
- dysphagia made worse by eating food or by lying down.
- others may be asymptomatic.
rolling:
- dysphagia from compression of the oesophagus
- early satiety
- inability to hold solid foods down
describe what a congenital diapghragmatic hernia is?
- condition in new born babies where there is incomplete development of the diaghram
- a large amount of the midgut structure can pass into the thorax, imparing lung function or in some cases lung development.
- babies present with cyanosis and respiratory distres.
how can you differentiate the pain from a bleeding duodenal ulcer and MI?
both will cause a sympathetic response to compensate for the inadequate perfusion of tissues = tachycardia
- MI is considerably more painful
- duodenal ulcer may have blood in stool.
The brain cannot localise visceral pain and it thinks it is coming from all over the skin.
C4 dermatome is on the shoulder (phrenic nerve is C3,4,5)
why is the pain from a sliding hernia worse after eating food?
food and fluid in the stomach will stimulate the release of gastric acid which will irritate the lower eosophagus
Midline Incision
Subcostal incision
Lanz approach to the appendix
Gridiron approach to the appendix
Pfannenstiel incision
Laparoscopic incision
Nephrectomy scar
midline incision:
uses?
advantages?
disadvantages?
uses:
- almost all abdominal operations where full access if required
advantages:
- its made of only fibrous tissue = almost a bloodless approach
- very quick access
- minimal restriction ot view
disadvantages:
- large unsightly scar
- higher risk of wound break down
- painful post op
paramedian incision:
uses?
advantages?
disadvantages?
uses:
- most operations that require good access to a specific half of the abdomen
advantages:
- provides better access to lateral structures than the midline approach
disadvantages:
- requires more time
- interrupts vessels and nerves passing from lateral to medial
transverse incision:
use?
advantages?
disadvantages?
use:
- surgery on the ascending or descending colon, duodenum, pancreas
advantages:
- less painful
- better cosmetic result
- no dernervation
- reduced chance of herniation
disadvantages:
- less exposure
- sloower access
subcostal incision:
uses?
advantages?
disadvanatges?
uses:
- biliary surgery on the right
- access to the spleen on the left
advanatages:
- good access to inferior surface of the liver
- less painful than a midline incision
disadvanatges:
- less exposure
- - must be closed in layers
Gridiron/Lanz approach to the appendix:
uses?
advantages?
disadvantages?
uses:
appendectomy
advanatges:
- layered closure of muscles provides excellent stregth to the wound
- good access to appendix and caecum
Disadvantages:
- limited and specific access
Pfannenstiel Incision:
uses?
advantages?
disadvantages?
uses:
- access to pelvic viscera
- caesarean
advantages:
- good access to pelvic cavity
- minimal scarring
- unlikely to interput nervous supply
disadvantages:
- poor access to abdominal viscera
- danger of damage to the bladder which sits just behind the abdominal wall
