Arterial system Flashcards
PAD d/t
Thromboembolism
Atherosclerosis (m/c)
Trauma
Chronic arterial stenosis in the LL
Intermittent claudication- Not present at rest, precipitated by walking a claudication distance, relieved on taking rest either sitting or standing for < 5 mins.
M/c Superficial femoral artery- posterior calf pain
Leriche’s syndrome- Buttock claudication, impotence
Rest pain
Pain exacerbated by elevation, better while hanging legs out of bed.
Ulceration, gangrene
Chronic Limb Threatening Ischemia (CLTI)- Rest pain +/- ulceration and gangrene
Chronic ischaemic legs- Normal sensation, red and swollen (elevation causes pallor)- sunset foot sign, warm to touch, no paralysis, CRT >10 sec.
Doppler USG
Indicates moving blood- does not mean this is sufficient for limb viability.
Ankle Brachial Pressure Index (ABPI)
Normal 0.9-1.4
<0.4- CLTI
ABPI could be normal due to formation of collaterals- Check ABPI after exercise- A drop of >20% indicative of arterial disease.
>1.4 in diabetics- due to medial sclerosis - so use Toe brachial pressure instead as diabetics seldom involve toe arteries.
TBI< 0.6 indicative of arterial disease.
Duplex doppler ultrasound
CTA MRA
CTA> DUS
MRA- claustrophobic, gadolinium contrast nephrogenic
CTA- ionising radiation, ionising contrast
Conservative management
0.1 decrease in ABPI below 0.9- 10% increase in risk of major cardiovascular event.
ABPI<0.5- 2x more chance of deteriorating further than with ABPI >0.5.
Claudication is a marker of silent coronary arterial disease.
Risk factors- Smoking, DM, hyperlipidaemia, HTN.
Exercise 2 hrs per week for 3 months
Smoking cessation, weight loss
Statins (prescribe even if lipid profile is normal as they will stabilise atherosclerotic plaques), HTN and DM medications, Aspirin 75 mg OD/ Clopidogrel 75mg OD.
Transluminal angioplasty- Percut puncture of femoral artery under LA- pushed into arterial occlusion- Balloon inflated - check angiogram done.
Long occlusions- Subintimal angioplasty- creates new lumen.
Stent.
Surgical management
In cases with CLTI/ failure of angioplasty.
AI occlusion- Aortobifemoral bypass. Unfit patients- Axillobifemoral bypass- Axillary artery subcut tunnelled
ABF- Vertical groin inscisions- femoral arteries exposed , Midline abd incision- Small bowel retracted to the right- Retroperitoneal tunnels from aorta to groin- Heparin 5000U given i.v and clamped- vertical incision over aorta, obliquely cut dacron graft end to side anastomosis done- grafts fed into the groin- end to side anastomosis done with femoral artery. Retroperitoneum closed over graft.
Superficial femoral artery- Femoropopliteal bypass.
If occlusion beyond popliteal artery into tibial artery- femorodistal bypass.
PTFE- Polytetrapolyethylene. Miller’s cuff or St Mary’s boot.
If one iliac involved- iliofemoral/ femorofemoral graft.
Gangrene
Acute Arterial Occlusion
Embolus/ thrombosis on existing plaque
Brain- TIA
Retina- Amaurosis fugax (Carotid artery to retinal arteries)
Mesenteric ischaemia
Acute limb ischemia
Sudden onset severe pain.
Sensory, motor loss. Insensate, paralysed limb.
Skin- Pale- Mottling with blanching- Fixed mottling.
Pulse absent distally. Femoral might even be thrusting-
ECG, CK MB, RFT, Imaging.
Managameny:
1. Pain Rx, i.v heparin 5000 U.
2. Embolectomy OR thrombolysis.
Thrombolysis if ischemia not very severe. Contraindicated- preg, recent CVA, bleeding disorder.
Rutherford classification of acute limb ischemia
Amputation
Indications:
Dead Limb
Gangrene
Deadly limb
Wet/ gas gangrene, spreading cellulitis
Dead loss limb
Severe rest pain, paralysis
