Surgical Techniques Flashcards
What are the three requisites of surgery?
Prevent infection
Haemostasis - but prevent excessive bleeding
Anaesthesia & paralysis - therefore ventilation req.
Describe conventional open repair of an AAA.
- Expose aorta via vertical or horizontal laparatomy
- Locate neck of aneurysm, give bolus of 5000U of heparin, clamp aneurysm and iliac vessels
- Open aneurysm sac and control back bleeding from lumbar/mesenteric vessels
- Sew Dacron tube/bifurcated graft into sac
- Close sac over graft
What are the complications of open repair of AAA?
- haemorrhage
- cardiac events
- resp. complications
- renal failure
- embolisation/thrombus of distal arterial tree
- cardiac ischaemia
- death (5%-10%)
- risk of infection
What are the complications of endovascular repair of AAA?
- graft migration
- fracture of supporting wires
- endoleak = blood moves around graft to keep expanding aneurysm
- infection
- dislodge thrombus with wire —> thromboembolism
What is the surgical mangement of a popliteal artery aneurysm?
Hunterian ligation Bypass surgery Endovascular stenting (across a joint, therefore risk of kinking)
What is the surgical management of carotid artery stensosis?
Carotid endartectomy (within 2wks of symptom onset)
- Expose carotid artery and bifurcation via incision ant. to sternocleidomastoid (preserve vagus and hypoglossal nerves)
- 5000U of heparin, clamp artery, and perform longitudinal arteriotomy (maintain perfusion via shunt)
- Remove atheroma and close artery (primarily or with patch)
What are the complications of a carotid endartectomy?
- wound haematoma (may req. evacuation)
- emboli (give heparin/dextran infusion to reduce risk of stroke)
- thrombosis causing stroke (2%-4%; urgent re-op req.)
What are the indications for a carotid endartectomy?
Otherwise fit patients presenting with carotid territory symptoms within past 6mnths who have an ipsilateral 50%-99% stenosis (when 75yrs
- very recent symptoms (within 2wks)
- medical comorbidities
- contralateral occlusion
What are the advantages of carotid angioplasty compared to carotid endartectomy?
- less invasive
- no neck incision
- no risk of cranial nerve injury
- ?less CVS morbidity
- shorter hospital stay
What are the disadvantages of carotid angioplasty compared to carotid endartectomy?
- ?higher initial stroke risk (disrupting clot during procedure)
- access complications
- ?higher rate of restenosis
- stent causing new clots forming (antiplatelet therapy req.)
What are the features of an ileostomy?
Right iliac fossa
Spouted mucosa (contents are irritating)
Indications: IBD, inherited polyposis coli syndrome
Contents are continous and liquid
What are the features of a colostomy?
Left-sided: transverse, desc., sigmoid
- temporary: left iliac fossa or hypochondrium
- permanent: left iliac fossa
Flat (mucosa sutured to skin)
Indications: colorectal cancer, diverticular disease
Contents are intermittent and solid
What are the features of a loop stoma?
Loop of bowl exteriorised to body surface via skin incision.
Initially supported by rod to prevent slipping back into abdomen.
Functional: allows stool and gas to pass out
Non-functional: secreted mucosa
What are the features of an end stoma?
One opening only
Anus re-sited into abdominal wall after resecting rectum/anal sphincter
What is the landmark for needle thoracocentesis?
2nd ICS, mid-clavicular line, just above 3rd rib
What is the landmark for a chest drain?
Safe triangle:
- base of axilla
- lat. edge of pectoralis major
- ant./lat. edge of latissimus dorsi
- line superior to horizontal level of nipple and an apex below the axilla (5th ICS)
5th ICS, mid/ant. axiallry line
What are some of the complications of a chest drain?
- surgical emphysema
- haemothorax
- tube misplacement
- organ perforation
- blocked tube
- empyema
Describe how a chest drain works.
Underwater seal prevents air going back in.
Swinging column: fluid changes level during breathing (indicates changes in intrathoracic pressure - indicates effective ventilation) - no swinging could mean a blocked tube
Remove once leak is repaired and breathing spontaneously (if on CPAP risk or re-rupturing due to positive airway pressure)
Should never be clamped without senior review (could cause a tension pneumothorax)
What are the borders of the triangle of Calot?
Superior = cystic artery (inf. border of the liver) Medial = common hepatic duct Lateral = cystic duct
What are the contents of the triangle of Calot? Why are they important to determine before dissection within the triangle?
- Mascagni’s/Lund’s lymph node (enlarged in cholecystitis/cholangitis)
- +/-accessory right hepatic duct
- +/- sectoral bile ducts
Identify cystic duct before dissecting (severing common bile duct —> DEATH)
What is Mirizzi’s syndrome?
Gallstone(s) impacted at gallbladder neck/Hartmann’s pouch
—> chronic inflammation/fibrosis —> obstruction/erosion of common bile duct
Describe the consequences of gallstone obstruction in different locations within the biliary system.
Hartmann’s pouch = asymptomatic gallstone
Common bile duct/cystic duct = acute cholecystitis —> obstruction to gallbladder emptying —> bile stasis —> inflammation —> infection of bile (asc. cholangitis)
Pancreatic duct/sphincter of Oddi = gallstone pancreatitis
