Vascular Surgery Flashcards
How long can skeletal muscles tolerate ischemia?
6 h (unless acute on chronic ischemia)
Ischemia due to embolus vs thrombus
Embolus: Acute onset Prominent loss of function/sensation No Hx of claudication No atrophic changes Normal contralateral limb pulses
Thrombus:
Progressive onset or acute on chronic
Less profound loss of function/sensation(due to underlying collaterals)
May have Hx of claudication
May have atrophic changes
Decreased or absent contralateral limb pulses
Inv for acute limb ischemia
ABI ECG, troponin CBC PTT/INR Echo CT-Angio Angio
Tx of acute limb ischemia
Immediate Heparinization:
5000 bolus,
Then continuous to PTT 70-90
If impaired neurovascular status:
Emergent revascularization
If intact neurovascular status:
Time for W/U (angio, CTA…)
If embolus: embolectomy
If thrombus: thrombectomy, bypass graft, endovascular therapy
If irreversible ischemia: amputation
Treat underlying
Continue heparin, ad warfarin
Reperfusion complications
Compartment syndrome
Arrhythmia
RF, MOF due to toxic metabolites
Major RFs for lower extremity chronic ischemia
DM
Smoking
Older age
Minor RFs for lower extremity chronic ischemia
HTN Hyperlipidemia Obesity Sedentary lifestyle PMHx or FHx of CAD/CVD
Vascular claudication Sx
Pain with exertion (calf…)
Relieved by 2-5 min rest
No postural changes necessary
Reproducible
Critical limb ischemia
Rest pain
Night pain
Tissue loss
Pain most commonly over the forefoot
Wakes from sleep
Relieved by hanging the foot off bed
Ankle pressure < 40, ABI < 0.4, toe pressure < 30
Signs if chronic poor perfusion
Hair loss
Hypertrophic nails
Atrophic muscle
Ulceration
Infections
Slow capillary refill
Prolonged pallor on elevation
Prolonged rubor on dependency
Venous troughing (collapse of superficial veins)
Inv for chronic atrial insufficiency
Routine blood work
Fasting metabolic w/u
ABI
CTA/MRA (for planning intervention)
Arteriography (better than CTA/MRA, for tibial arteries
ABI interpretation
> 1.2: suspect wall calcification
> 0.95 normal
0.5 -0.8 claudication
< 0.4 critical
Tx of chronoc limb ischemia
RF modification
Exercise program (30 min x 3/w)
Foot care
Antiplatelet
Cilostazol
Indications of surgical intervention for chronic limb ischemia
Severe lifestyle impairing
Vocational impairment
Critical ischemia
Surgical interventions
Angioplasty +/- stenting
Endarterectomy
Bypass graft
Amputation, if:
Non suitable for above
Persistent serious infection, gangrene
Unremitted rest pain poorly controlled by analgesics
Mx of critical limb ischemia
If limb salvageable:
Arteriography
Duplex scanning
If not salvageable:
Amputation
(Analgesia in moribund pt)
Aortic dissection classification
Type A: involving ascending aorta
Type B: not involving ascending aorta
Acute: <2 wk
Chronic: >2 wk
What’s the most common etiology for aortic dissection?
HTN
RFs for aortic dissection
HTN
Marfan, EDS, other CTDs
Atherosclerosis
Coarctation of aorta
Bicuspid aortic valves
PDA
Cystic medial necrosis
Syphilis
Trauma
Arteritis (Takayasu)
Epidemio of AD
M> F
African-Canadian >…> asian
Peak age: 50-65 yr
If CTD: 20-40 yr
Sx of aortic dossection
Tearing pain radiating to back +
HTN (Asymmetric BP/Pulse between limbs)
Ischemic syndromes (occlusion of branches)
Unseating of aortic valve cusps ( new diastolic murmur)
Rupture into pleura, pericardium, retroperitoneum
Syncope
Inv for AD
CTA (mainstay)
ECG, troponin
CXR:
Pleural cap (pleural effusion in lung apices)
Widened mediastinum
Left pleural effusion
TEE:
Visualizes aortic valve and thoracic aorta
Lactate
Amylase
Mx of aortic dissection
Type A:
Urgent surgery
Type B: Medical Mx: IV antihypertensives Transition to oral meds ( BB, if BBs contraindicated, CCB) \+/- ACEI
Selective interventions for complications or refractory symptoms
+/- aortic stent-grafting
Aortic aneurism definition
Diameter at least x1.5 that of expected
RFs for AA
Smoking HTN PVD CAD CVD Age>70 FHx Degenerative Traumatic Mycotic (salmonella, staph) CTD Vasculitis Infectious (syphilis, fungal) Ascending thoracic aneurysms are associated with bicuspid aortic valve
Most common Sx of aorta aneurism
Asymptomatic
Most common site of AA
Abdominal
Inv for AA
CBC Lytes Urea Cr PTT,INR Type and cross
Abdominal U/S (screening, surveillance)
CT with contrast
Peripheral arterial doppler/duplex (R/O aneurisms elsewhere)
Screening for AAA
Men 65-74
Women 65 yr with cardiovascular disease and FHx of AAA
Men >50 with FHx of AAA
Indications for surgical Tx of AA
Ruptured
Symptomatic
Size > 5-5.9 cm
Ascending thoracic aorta aneurism if:
> 6cm
> 2x normal
> 4.5 cm + aortic regurgitation/marfan
RFs of carotid stenosis
For atherosclerosis: Smoking HTN DM Hyperlipidemia CVD CAD Older age
Inv for carotid stenosis
CBC
PTT/INR
Fundoscopy:
Cholesterol emboli in retinal vessels
Carotid bruit
Carotid duplex
CTA, MRA
Tx of carotid stenosis
RF modification:
Control DM, HTN, lipids
ASA +/- dipyridamole
Clopidogrel
Surgical
Indication fo carotid endarterectomy
Symptomatic and > 70% stenosis
Factors aggrevating Sx of varicose veins
Prolonged standing
PMS
Tx of varicose veins
Coservative:
Elastic compression stocking
Surgery
Indications for surgery of varicose veins
Failure of conservative treatment
Symptomatic varix:
Pain
Bleeding
Recurrent thrombophlebitis
Tissue changes:
Hyperpigmentation
Ulceration
Cosmetic
Inv for chronic venous insufficiency
Venous insufficiency and skin damage
Not required
Doppler U/S for pre-operative assessment
Tx of chronic venous insufficiency
Conservative:
Elastic compression stocking
Periodic rest/elevation
Avoid prolonged standing
Ulcer: multilayer compression bandage. ABx PRN
Surgical
Indications of surgical Tx for chronic venous insufficiency
If conservative measures fail
Recurrent large ulcers
Most common form of primary lymphedema
Lymphedema praecox
Starts in adolescence
Types of primary lymphedema
Milroy’s syndrome
Lymphedema praecox, starts in adolescence
Lymphedema tarda: starts after 35 yr
The most common cause of secondary lymphedema worldwide
Filariasis
The most common cause in north America: surgery, RT
Tx of lymphedema
Avoid limb injury
Early treatment of cellulitis
Skin hygiene:
Daily moisturizers
Early Tx of fungal/bacterial infection
Compression bandage
Compression garment
Gentle daily exercise of affected limb
Gradual increase in ROM
Must wear compression bandage when doing exercise
Massage (manual lymph drainage therapy)
