Indications for an abdomianl aortic aneurysm repair include:
A typical clinical presentation will have features like:
attend to ABCs
- insert 2 x large bore peripheral IV cannulae,
- target SBP ~90 mmHg to maintain end organ perfusion (analogous to the permissive hypotension)
- cross-match 6+ units of blood, consider activation of massive transfusion protocol
- obtain FBC, UEC, coagulation profile, VBG and ECG
provide titrated analgesia (e.g. fentanyl or morphine)
Treatment is surgical. o Endovascular Aneurysm Repair (EVAR) - Most effective for ruptured AAA - Insertion of a stent using a guidewire and angiographic guidance o Open Repair
Elective surgical repair is indicated in a male patient with an AAA >5.5cm
Management options include:
Conservative treatment involves:
o Watchful waiting
o Cardiovascular risk reduction AND
o Antiplatelet therapy
EVAR:
Open involves: Midline/ transverse incision Occlusion of vessels above and below Placement of prosthetic graft Associated risks with open: Acute renal failure Wound infection Aorto-duodenal fistulae Distal embolization Colonic ischaemia Graft infection Peri-operative bleeding
Complications can be categorise into:
Access site complications include:
Endograft complications include:
Systemic complications include: - Cardiopulmonary disease (e.g. Myocardial Infarction) - IV contrast complications Allergy Contrast nephropathy - Ischaemia – due to thrombosis, embolism, arterial dissection, obstruction related to positioning or kinking of the graft Renal Intestinal Lower limb Pelvic
Absolute contraindication is if there is asymptomatic complete occlusion on contralateral side.
Ddx include: stroke, seizures, space occupying lesion
- Lifestyle o Smoking o Obesity o Lack of exercise o Western diet - Disease o Previous TIA/stroke o Hypercoagulable state (Factor V Leiden, Protein C/S Deficiency, Antithrombin III deficiency) o Diabetes Mellitus o Hypertension o Dyslipidaemia o Other Atherosclerotic disease such as Coronary Artery Disaese or Peripheral Artery Disaese e.g. Carotid Stenosis o AF o Valvular Heart Disease
Acute mesenteric ischemia occurs mostly due to arterial compromise (embolism, thrombosis) in superior mesenteric artery. Hence, blood in stool, increase in lactate and CRP, pain
• Investigations: o FBC, UEC, VBG (done) o ECG o Erect CXR and Supine AXR o Mesenteric angiography/ CTA
• Definitive management:
- The traditional treatment of acute mesenteric arterial embolism is early surgical laparotomy with embolectomy since it provides rapid treatment and allows direct inspection of the bowel
o Endovascular therapy can also include balloon angioplasty with arterial stent placement
o Any infarcted bowel should be resected
What are you going to do?
Most likely diagnosis is acute limb ischemia.
I would take Hx, examination, investigations and plan management.
In terms of history,
O/E,
IX,
Mx:
• Contact vascular surgeon
Tx requires urgent assessment for viability of the limb + give antiplatelet, analgesia, anticoags
For viable limbs – they are revascularized using endovascular or thrombolytic method or surgical thrombectomy
For non-viable limbs – they are amputated
2.
Aetiology:
• Embolism
o Cardiac causes : AF, valvular vegetation, LV thrombus secondary to LV dysfunction,
o Non-cardiac: Atherosclerotic embolus, aneurysmal
• Thrombosis (most common for lower limb)
o Thrombosis of native vessel (atherosclerosis or aneurysm)
o Occlusion of a bypass graft
• Trauma
o Blunt
o Penetrating
• Rarer causes:
o Vasculitis
o Aortic dissection
Ix- ankle-brachial pressure index (ABPI), duplex doppler USS, CTA
• Definitive treatment:
o Thrombolysis – viable limb
o Surgical revascularisation/embolectomy – threatened limb
o Amputation – non-viable limb
What are the clinical signs that you will assess to determine whether the leg is salvageable, or that it is beyond help and needs amputation?
Likely diagnosis is acute limb ischemia.
The limb is non-viable if there are signs of tissue loss, sensory loss, nerve damage.
The limb is viable if it has none of these and artery anatomy is defined.
The clinical signs to determine are:
The main factors to consider are viability, severity, patient’s age and comorbidities.
The foot is decided whether it is viable or not by assessing the tissue necrosis, nerve damage, sensory/motor loss.
All patients should have aggressive risk factor modification
All patient with diagnosis should be started on medication
For moderate and disabling claudication patients medical therapy and exercise program are started. If this fails they are assessed for anatomy definition and surgical revascularisation.
For critical ischemic limbs, urgent revascularisation (balloon angioplasty with stenting or bypass grafting) should be done and consider amputation if required due to non-viable limb.
The level of the amputation is dictated by the extent of the disease, healing potential of the stump, and rehabilitation potential of the patient. The decision is made through physical examination and objective testing.
On physical examination, they should have arterial pulse just proximal to the level of amputation to ensure healing. Should be inspected for gangrene/ulcers, infections, pulselessness, pallor, coldness and all affected limb should be amputated.
Objective testing include, ankle pressures, toe pressures, transcutaneous oximetry, skin perfusion pressure (measurement of Skin Perfusion Pressure is with laser Doppler a non-invasive test.)
Above knee amputation (femoral)
- Bone transected 12-15cm (1/3) above knee, this is common in end stage PVD
Below knee amputation (tibial)
Through knee
- Requires wide stump, unpopular
Syme’s ankle disarticulation (malleolar)
- Only used in trauma and diabetics, prosthetic is difficult
Lisfrank or Chopart- midfoot amputation
Transmetatarsal
- For diabetics, gangrene toes
2. Ix: • Bloods: FBC, UEC, BSL, lipids, ESR/CRP, Coags • ECG • Duplex Doppler USS upper limb • CTA/ conventional angiography • Echocardiography
Most common cause for upper limb PVD is from emboli (different to LLI which is thrombosis)
- Commonly source is from cardio, after AF, valvular disease, MI, tumour (atrial myxoma)
Thrombosis
Trauma
- Blunt or penetrating trauma
Medical treatment is with Anticoagulation – UFH IV bolus + infusion
•Referral to a vascular surgeon for either: o Intra-arterial thrombolysis o Embolectomy o Angioplasty with stenting o Bypass grafting o Amputation
Acute mesenteric ischemia occurs mostly due to arterial compromise (embolism, thrombosis) in superior mesenteric artery. Hence, blood in stool, increase in lactate and CRP, pain