13.01.23 Vascular

Signs of arterial trauma

• • Hard

    • Pulsatile bleeding

    • Arterial thrill

    • Bruit

    • Absent distal pulses

      • But cf compression/tension

    • Expanding haematoma

  • Soft

    • Haemorrhage

    • Neurological abnormality

    • Decreased pulse compared to contralateral side

    • Proximity to bony injury or penetration

Arterial trauma

• • Vertebral artery

    • Very difficult to access surgically

    • Shut off with coils

      • Rely on collaterals

  • Aorta

    • Fixed at ligamentum arteriosum and mobile elsewhere => Tends to tear at this point

    • Fix with a stent graft

  • Stop-gap measures

    • Outcome is better if you buy time to stabilise other stuff, then fix the vasculature later

    • Shunts

  • Tamponade

    • Is generally your friend

      • e.g. In kidneys, pelvis : DON'T release the pressure!

    • Doesn't work in the thorax as the lungs are compressible

Diabetic feet

• • Factors

    • Predisposing

      • Neuropathy

    • Precipitating

      • Nail in shoe

    • Perpetuating

  • Gangrene

    • Dry will auto-amputate

    • Wet = Infection = Problem

      • Treat with aggressive ABX

  • Magic bullets?

    • Hyperbaric oxygen works well but is not used much as there's no money to be made :)

    • Larvae, PDGF, GCSF, EGF

    • Skin substitutes

Limb ischaemia

• • 3 levels - Need disease at each before you get gangrene => Hard to treat at that stage

    • Above the inguinal ligament

    • Above the knee

    • Below the knee

Intermittent claudication

• • Pain in muscle on exercise

    • Usually calf, but can also be thigh or buttock

      • => Site of stenonis, e.g. for buttock pain it must be above the bifurcation of the common iliac

  • Prognosis

    • 50% improve with exercise alone (esp. nordic walking)

    • 30% stay the same

    • 5% get worse

    • 15% will be dead from stroke or MI within 5 years

  • Intervention

    • Only 5% require intervention

    • 1% require amputation

    • Cilostazol => Vasodilatation

      • 3-type phosphodiesterase inhibitor

  • Risk factors

    • A ntiplatelet

    • B P

    • C holesterol

    • D iabetes

    • E xercise

Critical limb ischaemia

• • Definition

    • Rest pain

    • Requiring analgesia (frequently opioids)

    • Present for more than 2 weeks or with tissue loss

  • Pressure measurements

    • ABPI is useless

    • 50 mmHg at the ankle or 30 mmHg at the toe implies CLI

  • Prognosis

    • 25% require major amputation

    • 90% require intervention within a year

Acute limb ischaemia

• • All the "P"s

    • Pallor increase

    • Pulses decreased

    • Perishing cold

    • Pain

    • Paraesthesia

    • Paralysis

  • Damage

    • Nerves after 30 mins

    • Muscle after 6 hrs

    • Skin after 48 hrs

      • => Can look quite normal from the outside

  • Causes

    • Thrombosis

      • Most common cause

      • Presents acutely/sub-acutely

      • Patients tend to be claudicants

      • Other limb is often abnormal

    • Embolisation

      • Second most common cause

      • Clots can come from heart or lower down

      • Sudden onset

      • Usually no Hx of PVD

      • Opposite limb is normal

      • Often identifiable source

        • 80% AF

        • 10% post-MI

        • 10% aneurysm

    • Graft thrombosis / post-angioplasty

  • Treatment

    • Be very careful of re-plumbing!

      • Potassium load from dead cells => MI

    • Fogarty balloon catheter to withdraw clot

    • Catheter-directed lysis

      • Prevents complications of systemic thrombolysis

      • Can also visualise underlying cause

Aneurysms

• • Screening programme in place for men over 65

  • Risk factors

    • Male x4

    • Smoking x6

    • FHx x4

  • 4% of men >60 have a >3 cm AAA

  • Mortality

    • Elective repair: 1-2 % at SGH, 5-9 % nationally

    • Rupture: 80 %

Arteries of the pelvis and leg

ACCORD Trial

• • Targeting Blood Sugar to Near-Normal Levels Does Not Reduce Cardiovascular Events But Increases Mortality in Persons with Diabetes at High Risk

    • Intensive strategy group had a 22 percent higher risk of death, mostly from cardiovascular causes

    • Increased risk began emerging within 1 to 2 years

  • Results might not apply to patients who are at lower risk of cardiovascular disease than the ACCORD participants or to patients with more recently diagnosed type 2 diabetes

  • Intervention:

    • Standard strategy aimed for HbA1c 7-7.9 % (similar to what is normally achieved)

    • Intensive strategy aimed for HbA1c <6 % (similar to non-diabetic level)

  • Reason is unclear

Notes

• • Arteries spasm, veins don't => Venous bleeding is often more severe in the medium term

  • 17% of patients with a diabetic foot ulcer will be dead within a year

  • Common iliac bifurcates a bit above the inguinal ligament

  • Statins => Remodelling and plaque regression

  • Tight glucose control may be worse

  • Walking requires 50-90% more energy with an artificial limb, so patients often don't

  • Venous gangrene => Look for underlying cause (e.g. cancer)