Vascular Surgery Flashcards
Definition/Epidemiology/Pathophysiology of an Abdominal Aortic Aneurysm (AAA)?
Presentation of Abdominal Aortic Aneurisms?
~ 75% of aortic aneurysms are asymptomatic and are discovered incidentally either as a pulsatile abdominal mass on physical examination or on abdominal imaging done for another reason.
A small proportion will present with symptoms related to pressure on adjacent structures:
- Back/flank pain
- Ureteric compression
- Caval compression (tachycardia, diaphoresis, nausea, vomiting, pallor, weakness, lightheadedness, and dizziness)
Most of the clinical symptoms due to aortic aneurysm are related to aneurysm rupture or embolism of mural thrombus
Risk Factors for Abdominal Aortic Aneurisms?
Complications of AAA?
Investigations for AAA?
Surveillance of Asymptomatic AAA?
Types of Operation and Indications for AAA Repair?
Open Surgical Repair (OSR) or Endovascular Aneurysm Repair (EVAR)
- Elective: when the aneurysm size is exceeding the 5.5 cm threshold or when the rate of growth is >1cm per year
- Emergency: Rupture/Symptomatic
Method/Complications of OSR of AAA?
Open Surgical Repair (OSR) is done through midline incision (laparotomy) with mortality around 5%. The aneurysm is replaced with a synthetic graft
Method/Complications of EVAR of AAA?
In Endovascular Aneurysm Repair (EVAR) a stent graft is delivered through groin incisions to exclude the aneurysm. Done using radiation and nephrotoxic contrast is used. No Aortic clamping is needed, less early postoperative mortality than OSR, but higher re-intervention rate due to endoleak which requires lifelong surveillance with US or CTA
What is the principle of Permissive Hypotension
Following aortic rupture, systolic BP is kept between 70-80 mmHg to maintain vital organs perfusion.
Stroke vs. TIA?
~ 80% of strokes are _______ and 20% ______
~ 80% of ischaemic strokes affect the _____________. The main cause of which is _____________________.
~ 80% of strokes are ischaemic and 20% hemorrhagic (intracerebral/subarachnoid)
~ 80% of ischaemic strokes affect the carotid territory the main cause of which is thromboembolism of the internal carotid artery (ICA)
Risk Factors for Stroke?
Clinical Presentation of a Stroke?
80% of strokes are ischaemic of which 80% are in the carotid territory.
Carotid territory classical symptoms:
- Hemimotor/hemisensory signs
- Monocular visual loss (Amaurosis Fugax: sudden, short-term, painless loss of vision in one eye)
- Higher cortical dysfunction (dysphasia, visuospatial neglect etc.)
General:
- Facial drooping
- Arm weakness
- Speech difficulties
- Time to call emergency services.
Investigations for Stroke?
Medical Treatment of Asymptomatic Stroke
Asprin
clopidogrel
Statins
Smoking Cessation
Control of BP/Diabetes
Surgical/Endovascular Treatment of Stroke
- Complications?
- Contraindications?
What is Acute Lower Limb Ischemia?
Sudden decrease in limb perfusion that threatens limb viability
Acute lower limb ischaemia is associated with high risk of limb loss, up to 30-50% at 30 days.
Causes of Acute Lower Limb Ischemis
Clinical Features of Acute Lower Limb Ischemia?
6 P’S
- Pain
- Pallor
- Pulselessness
- Perishing Cold
- Paresthsia
- Paralysis
Classification of Acute Lower Limb Ischemia?
Rutherford’s CLassification
Initial Management of Acute Lower Limb Ischemia?
- If there is clear evidence of acute ischemia on history and exam, do not delay definitive treatment and give IV heparin 5000 units bolus
- Give O2
- IV access and fluids if dehydrated
- Bloods – FBC, U&E, coagulation profile, troponin, glucose, group & save
Management Options for Category III Lower Limb Iscehmia?
III Irreversible Leg Ischemia
Resuscitate and stabilize before considering amputation
Management Options for Category IIb Lower Limb Ischemia?
IIb Immediately Threatened
Start initial management with urgent Computed Tomography Angiography (CTA) followed by urgent revascularization with surgery (thromboembolectomy +/- bypass surgery)
Management Options for Category I/IIa Lower Limb Ischemia?
Category IIa (threatened) and Category I (viable) limb
Revascularization options include endovascular catheter-directed thrombolysis in addition to open surgical thromboembolectomy and bypass.
Complications of Reperfusion and their treatments
Mostly occur after delayed revascularization