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History

  • Longstanding ulcer on right leg
  • Vascular risk factors
  • MI
    • Ask about symptoms since then
  • Had various operations

What's missing?

  • ?Diabetes - big miss
  • ?Family history
  • ?CKD
  • ?Claudication - big miss
  • May get some information from a better peripheral vascular examination/history (e.g. arterial = put leg down to relieve symptoms; venous = leg down makes it worse)
  • ?Neurological problems - TIA and cerebrovascular disease
    • ?Peripheral neuropathy - paraesthesia, numbness
    • NB: neuropathic ulcers are often painless
  • ?Fundoscopy - retinal microvascular disease, hypertensive changes

Letter from Dr Robert Allen

  • Catheter put into left leg to look at right leg, because if we're suspecting calcification in the right femoral artery, it's a bad idea to stick a catheter in that artery:
    • Prevent vascular injury, embolus/thrombosis, dissection
  • Result: multiple pathologies in the right artery
  • He put a balloon in some right-sided arteries to make them patent -- improve arterial supply
  • Dissection possible consequences
    • Rupture
    • Occlusion (due to flap)
  • 10mm stent, but only dilates to 8mm because the stent is a springy mesh, and the vessel is pushing inwards on the lumen (vessel is calcified, and is restricting the stent to stop it expanding to its maximum extent). Then they blow up the balloon to expand the stent
    • Stretched longitudinally over catheter = narrows the stent. When you unstretch it = it dilates
  • After stent- patient needs antiplatelet agents to prevent thrombus formation (stent causes endothelial injury, can result in thrombus formation)
  • Worst complication: loss of the limb
  • Data: drive-by stenting is not beneficial - risks outweigh the benefits assuming he's asymptomatic in the left leg
    • Indication: ulcer OR claudication (any symptoms basically) - this threatens the limb
  • Ulcer still not fixed
  • Femoral popliteal bypass - pain is a bit better but the ulcer hasn't healed
    • Pain getting better - there may be an arterial component to the problem
  • But ultimately the ulcer increases in size
  • Venous hypertension --> letting the arterial flow come in causes more oedema --> venous ulcer gets worse (exacerbating venous problem, worsening oedema and worsening the ulcer)
    • Oedema worsens ulcer because it makes a bigger space between the vessel and the ulcer (so it's harder for immune system to access it)
  • Signs of infection
    • Red around the border - probably not inflammatory - it's new epithelialisation: a healthy appearance
      • Also cellulitis - radiating redness around the ulcer; has a radiating border that can
    • Lymph vessel involvement - proximally to the lesion - lymphangitis (up medial aspect of thigh)
    • Lymphadenopathy - inguinal/femoral lymph nodes involved
    • Pus - standing up will cause it to drip out of the ulcer
    • Not usually smell in ulcer - that occurs with anaerobic organisms (not very common in exposed ulcer)
    • Yellow stuff in the wound = ulcer slough: densely adherent necrotic tissue deriving from surrounding tissue and from the base of the ulcer, can include fat etc; not a marker of infection necessarily. Get a squeeze bottle with sterile water and wash - slough won't move, but pus will move.
    • Granulation tissue = red stuff near the slough (good sign)
  • Clinically this is not an infected ulcer
  • There is oedema in right leg - suggests a local cause (rather than CCF or cirrhosis)
  • Anaesthetist wants to know about possible cardiac problems (will anaesthesia kill him???)

Lower limb doppler

  • Get Ankle Brachial Index to compare pressures between upper and lower limbs
  • <0.9 is a problem
  • Right limb is good, left limb is bad - this indicates arterial insufficiency in left limb
  • To feel pulses in oedematous patient, you just keep pressing to feel the peripheral pulses
    • Maybe the technician hasn't taken the time to push the oedema out of the way
  • Doppler arterial waveform normally has 3 peaks
    • 3 components of arterial pressure wave
      1. Ventricular contraction
      2. Closure of the aortic valve
      3. Reflection of pressure wave from the periphery
  • Vessel relies on elasticity to give a good waveform (to see the tiny little perturbations in Doppler US)
  • Tibial vessels = monophasic = only ventricular spike = vessel is hardened/calcified
  • Note: all these waveforms are based on the vessel wall being able to pick up the wave or not (i.e. response to pressure - the waves will still pass through the column of blood, but won't perturb the wall)
  • ABI: symptoms below 70% and rest pain below about 50%. 30% would be very bad.

Venous incompetence duplex

  • Incompetence in the perforators
  • Incompetence in the superficial system
  • Incompetence in the deep venous system
    • This is most important
    • This is due to valvular incompetence
    • Valves damaged or destroyed due to post-DVT/superficial thrombophlebitis (past history). DVT can cause valve destruction. The main cause is genetic.

Swab

  • Penicillin-resistance Staph Aureus
  • Not tested for anaerobic (but it doesn't smell)
  • Polymorphs++
  • Colonisation rather than infection ? Mixed growth
  • Clinical appearance - didn't look infected
  • So there's no point in acting on the information (he's already on antibiotics and we'll probably withdraw them)
    • There's actually no point in ordering the test in the first place
    • NB: development of resistance in chronic antibiotic use - inevitable
  • Clinical judgement - this doesn't need antibiotics, so why do the test?

Arterial duplex

Oedema case follow up

  • In hospital management
    • Treatment with morphine analgesia, leg elevation and compression bandaging for 5 weeks, ulcer decreased in size
  • Follow up
    • Oct 2004, ulcer almost healed, placed in compression stocking, needs vein graft follow-up with duplex
      • Worry - occlude the artery too much, causing ischaemia; don't be too tight with bandage
    • Jan 2005 - vein graft duplex showed stenosis at proximal anastamosis
    • 31-01-05 angiogram confirmed stenosis
    • 4-02-05 Planned revision of vein graft on 08-02-05
    • 8-02-05 Vein graft occluded clinically, confirmed on duplex
    • July 2005 - no claudication, no recurrence of leg ulcer, compression stocking in place
  • Don't do anything now, even though the graft is occluded
  • This tells us:
    • Wasn't primarily an arterial problem
    • He has sufficient supply anyway because he has collateral formation - during the previous stenosis

Prognosis

  • MI, stroke are possible
  • Risk of death is 30% in the next 5 years due to his vascular disease
    • So we need secondary prophylaxis! Aspirin/statins are so effective because you're starting off at a low point.