vascular surgery back to basics andrew b hill md facs frcs vascular and endovascular surgery the...

Vascular SurgeryBack to Basics

Andrew B Hill MD FACS FRCS

Vascular and Endovascular Surgery

The Ottawa Hospital

OUTLINE• Acute limb ischemia

• Claudication

• Critical limb ischemia

• Aortic Aneurysm

• Aortic dissection

• Varicose veins

• Chronic venous insuffciency

• Superficial thrombophlebitis

Acute Limb Ischemia

Mrs. Whitelegg

• ID:• 75 yo lady

• Active - walks her dog ~2 kms daily

• has not needed to see a doctor in the last 10 years.

Acute Limb Ischemia

Mrs. Whitelegg

• PMHx/PMSx:

• remote TAH-BSO

• social smoker quit in the 1960’s

• No: DMHTN

hyperlipidemia

Acute Limb Ischemia

Mrs. Whitelegg

• HPI:• watching TV

• sudden onset of numbness in her right leg - “like it went dead”

• Unable to walk

• constant, severe pain eventually involving the entire right leg.

• Called amblance

Acute Limb Ischemia

Mrs. Whitelegg

• What is the diagnosis?

Acute Limb Ischemia

Mrs. Whitelegg

• Acute limb Ischemia:

• abrupt cessation of arterial blood flow

• hypoperfusion of tissue

• threatened limb viability

Acute Limb Ischemia

Mrs. Whitelegg

• Vital Signs

• BP:140/90 mmHg

• HR: 150 bpm

irregularly irregular

• Afebrile

Acute Limb Ischemia

Mrs. Whitelegg

• Exam

Normal heart sounds

Chest clear IPPA

No pulsatile masses in her abdomen

No carotid, abdominal or femoral bruits

Acute Limb Ischemia

Mrs. Whitelegg

• Exam

Pulses:

Left:

+ femoral, + politeal, + DP, + PT

Right:

- femoral, - popliteal, - DP, - PT

Acute Limb Ischemia

Mrs. Whitelegg

• Exam

– Normal heart sounds

– good a/e bilat

– No pulsatile masses in her abdomen

– No carotid, abdominal or femoral bruits

– Pulses:

• L: + femoral, + politeal, + DP, + PT

• R: - femoral, - popliteal, - DP, - PT

– R foot is colder and paler than L

– Decreased sensation in R foot

– Able to move toes but difficulty with plantar and dorsi flexion

– Absence of trophic changes in her lower extremities (no hair loss, thickened nails, or thin, flaky or shiny skin)

Acute Limb Ischemia

Mrs. Whitelegg

• Exam

• R foot is colder and paler than L• Decreased sensation in R foot• Able to move toes but difficulty

with plantar and dorsi flexion• Absence of trophic changes in

her lower extremities (no hair loss, thickened nails, or thin, flaky or shiny skin)

Acute Limb Ischemia

Mrs. Whitelegg

• What are the 6 P’s of Acute Limb Ischemia

Acute Limb Ischemia

Mrs. Whitelegg

• 6 P’s of Acute Limb Ischemia

• Pain• Palor• Polar/poikilothermia• Paraesthesia• Paralysis• Pulselessness

Acute Limb Ischemia

Mrs. Whitelegg

• Classify Acute Limb Ischemia. In which category is Mrs. Witelegg?

Class Sensory deficit Motor deficit Prognosis

1 None None Not immediately threatened

2a Mild-moderate None Salvageable if treated promptly

2b Significant Mild-moderate Salvageable if immediately treated

3 Profound Profound Irreversible limb damage- likely amputation

Acute Limb Ischemia

Mrs. Whitelegg

• Your working diagnosis is acute limb ischemia.

• You order CBC, electrolytes, BUN, Cr, PTT/INR (all of which comes back normal), type and cross-match blood, and a saline infusion is started.

• CXR is unremarkable

• ECG is as follows:

Acute Limb Ischemia

Mrs. Whitelegg

• What is the most likely etiology of ALI in Mrs. Whitelegg?

• Cardiogenic embolism

Acute Limb Ischemia

Mrs. Whitelegg

• What in her history and physical supports this diagnosis?

• lack of atherosclerotic risk factors

• no previous claudication (she walked her dog 2 km/day)

• atrial fibrillation

• normal left extremity pulses

Acute Limb Ischemia

Mrs. Whitelegg

• Based on her physical examination, what is the highest point of obstruction of arterial flow?

• R ileo-femoral region

Acute Limb Ischemia

Mrs. Whitelegg

• How long can a limb be without blood flow before irreversible tissue damage ensues?

• 4-6 hrs

Acute Limb Ischemia

Mrs. Witelegg

• What is the surgical management of this condition?

• R femoral embolectomy

• Can we proceed to the OR without any imaging studies? If not what studies can be perfomed?

• Because of the classic history and physical findings, and because of the presence of class 2b ischemia, immediate surgery is indicated without delay for imaging.

• Angiography can be performed in certain conditions of ALI– when the suspected etiology is arterial thrombosis (i.e.

in preparation for bypass surgery)– when the patient has class 1 or 2a ischemia

Acute Limb Ischemia

Mrs. Witelegg

• What medical therpay is available for ALI and when is it indicated?

• Lytic therapy (i.e. with t-PA) is used to dissolve the clot. It is a good option in the setting of acute arterial or graft thrombosis. It is not indicated in the setting of trauma or when the patient can not wait more than 24-48 hrs, as the therapy requires that period of time for clot dissolution. ( i.e. class 1 or early 2a ischemia)

• IV Heparin will not dissolve the clot but will prevent further propagation, and is only indicated if there is a delay to surgery

Acute Limb Ischemia

Mrs. Witelegg

• The patient is booked for emergency embolectomy

• Under local anaesthesia, a small incision is made over the R groin. The femoral artery is exposed and controlled with vessel loops. A small arteriotomy is made and the clot is removed proximally and distally using a fogarty balloon embolectomy catheter.

• The arteriotomy is repaired and the foots “pinks up” after blood flow is returned. There is a palpable DP and PT pulse.

• The patient is returned to the recovery room.

Acute Limb Ischemia

Mrs. Witelegg

• At 3 am you get paged by the recovery room nurse. Mrs. W is complaining of significant pain in her leg, it is more swollen and the DP and PT are no longer palpable.

• In addition, her urine output has diminished and she is peeing out dark urine which tested positive for “blood” on the urine dipstick.

Acute Limb Ischemia

Mrs. Witelegg

• What is happening to Mrs. W?

– Reperfusion syndrome: occurs as a result of blood flow going back into previously damaged tissue, causing rhabdomyolysis and compartment syndrome..

• Rhabdomyolysis: Liberated myoglobin from dead muscle cells enters the blood stream resulting in renal tubular obstruction and direct nephrotoxicity causing renal failure. Myoglobinuria is a false positive on the urine dipstick test for blood.

• Compartment syndrome: Free oxygen radicals are created with reperfusion. These result in increased tissue edema, with in the limited facial compartments of the lower leg, this further decreases capillary blood flow and worsens the ischemia and tissue damage, causing further edema. Pain out of proportion, pain on passive stretch and high pressures in the compartments suggests compartment syndrome.

Acute Limb Ischemia

Mrs. Witelegg

• How should reperfusion syndrome be managed?

– Compartment syndrome is a surgical emergency and is managed by 4-compartment fasciotomies.

– Rhabdomyolysis should be managed with aggressive IV fluids, diuresis and alkalinization of urine.

Acute Limb Ischemia

AORTIC DISSECTION

Definition

• spontaneous tear in aortic intima allowing blood to be driven between the aortic intima and media

– acute < 2 weeks– chronic > 2 weeks

Aortic Dissection

Classification

• DeBakey

• Type I - involves ascending and descending aorta

• Type II - ascending aorta only

• Type IIIA - descending thoracic aorta

• Type IIIB - Type IIIA plus abdominal aorta

• Standford

• Type A - ascending aorta and aortic arch; emergency

• Type B - aorta distal to subclavian artery; emergency surgery if complications of dissection

Aortic Dissection

Etiology

• HYPERTENSION, usually uncontrolled

• TRAUMA, usually deceleration injury (falls, MVAs)

• other: cystic medial necrosis, atherosclerosis, connective tissue disease (Marfan’s syndrome, Ehlers-Danlos syndromes), congenital conditions (coarctation of aorta, bicuspid aortic valves, PDA), infection, arteritis (Takayasu’s)

Aortic Dissection

Epidemiology

• incidence 5.2 in 1,000,000• male:female = 3:1• small increased incidence in African-Canadians (related to

higher incidence of hypertension)• lowest incidence in Asians

Aortic Dissection

Clinical Features

• SUDDEN ONSET SEVERE CHEST PAIN RADIATION TO THE BACK (INTERSCAPULAR) +/-....

• hypertension• asymmetric BP’s and pulses between arms• ischemic syndromes due to occlusion of aortic branches:

coronary (MI), carotid (stroke, Horner’s syndrome), splanchnic (ischemic gut), renal (kidney failure)

• “unseating” of aortic valve cusps (new diastolic murmur)• rupture into pleura (dyspnea, hemoptysis) or peritoneum

(hypotension, shock) or pericardium (tamponade)• lower limb ischemia (cold legs)

Aortic Dissection

Investigations

• CT scan is gold standard

• CXR

• pleural cap

• widened mediastinum

• left pleural effusion with extravasation of blood

• TEE

• ECG: LVH (90%), +/- MI, pericarditis, heart block

• aortography, MRI

Aortic Dissection

Treatment

• Type A• EMERGENCY CARDIAC SURGERY

• may require putting patient on pump, hypothermic circulatory arrest, valve replacement, coronary re-implantation of aortic root

• resection of intimal tear, reconstitution of flow through true lumen, replacement of the affected aorta with graft

• Type B• MEDICAL MANAGEMENT

• very rarely urgent operation for complications (expansion, rupture, gut/leg/renal ischemia, ongoing pain

Aortic Dissection

AORTIC ANEURYSM

Definition

• localized dilation of an artery that is 2 x its normal diameter

• true aneurysm: involving all vessel wall layers

• false aneurysm: disruption of aortic wall with containment of blood by some layers of the aorta or a fibrous capsule made of surrounding tissue

Aortic Aneurysm

Aortic Aneurysm

Aortic Aneurysm

Etiology

• DEGENERATIVE (matrix metalloproteinases)

• atherosclerosis association• infection• cystic medial necrosis• trauma• vascultitis• connective tissue disease (Marfan syndrome, Ehlers-Danlos)

Aortic Aneurysm

Epidemiology

• incidence 5 to 32 per 100,000 for AAA

• high risk groups:• 65 years and older• male:female = 4:1• smokers• peripheral vascular disease, CAD, CVD• family history of AAA

Aortic Aneurysm

Clinical Features

• Vast majority ASYMPTOMATIC• • RUPTURE

• back pain• hypotension/syncope• pulsatile abdominal mass• ~100% mortality if untreated

Aortic Aneurysm

Investigations

• abdominal US (100% sensitive)

• CT

• Aortogram (false negative normal lumen size due to thrombus formation)

Aortic Aneurysm

Treatment

• Risk of rupture depends on size• <5 cm <5% / yr• 5-6 cm 10% / yr• 6-7 cm 15-20% / yr• >7 cm >20% / yr

• Risk of dying from aneurysm surgery = ~5%

Aortic Aneurysm

Treatment

• Operate when

• AAA reaches 5.5 cm in an otherwise healthy individual

• >5 mm expansion in 6 months• symptomatic AAA• Rupture

• contraindications: life expectancy < 1 year, terminal disease (cancer), significant co-morbidities (recent MI, unstable angina), severe dementia, advanced age

Aortic Aneurysm

Treatment: Surgical

• Surgical options:

• open surgery with graft replacement

• Endovascular aneurysm repair

Aortic Aneurysm

Ruptured Aortic Aneurysm

• EMERGENCY

• clinical diagnosis class diagnostic triad (50% cases)

• sudden onset back pain

• shock (syncope/hypotension)

• pulsatile mass

• U/S in emerg or CT if stable

• IV access, start fluid resuscitation, cross and match

• EMERGENCY LAPAROTOMY and CLAMP AORTA

• Prognosis

• 100% mortality untreated, OR mortality rate 50%; 90% total mortality

Aortic Aneurysm

CLAUDICATION

Clinical Features - Claudication

• Pain with exertion (usually calves)

• relieved by short rest - two to five minutes

• reproducible

• P/E• hair loss, hypertrophic

nails, atrophic muscle• pulses may be absent

at some locations

Etiology

• blockages in arteries to lower extremities due to atherosclerosis

• Risk factors• smoking• DM• HTN• hyperlipidemia• family history• obesity• sedentary• male gender

Investigations

• Ankle Brachial Index

• Angiogram

Ankle Brachial Index (ABI)

• Measure brachial pressure

• Measure ankle pressure

• Divide ankle by brachial pressure

• (example 80/160 = 0.5)

• Normal = > 0.9

Acute Limb Ischemia

Treatment

• CONSERVATIVE

• risk factor modification• exercise program • cilostazol • anti platelet (ECASA, clopidrogel) for MI / stroke risk

• surgical• indications: claudication interfering with lifestyle• options: endovascular, PTA, arterial bypass grafts

CRITICAL LIMB ISCHEMIA

CRITICAL LIMB ISCHEMIA

night painrest pain

tissue ischemia

Clinical Features - Critical limb ischemia

• Pain at rest in foot, worse at night

• relieved by short rest - two to five minutes

• reproducible

• pulses may be absent at some locations

• P/E

• hair loss, hypertrophic nails, atrophic muscle

• ruborous foot

• ulcers

• gangrene

Etiology

• blockages in arteries to lower extremities due to atherosclerosis

• Risk factors• smoking• DM• HTN• hyperlipidemia• family history• obesity• sedentary• male gender

Investigations

• Ankle Brachial Index

• Duplex ultrasound

• Angiogram

Treatment

• Surgical

– bypass

– gortex vs vein

• Endovascular balloon angioplasty

– limited durability

– less morbid

Venous disease

Varicose veins

Definition

• distended torturous superficial veins due to incompetent valves in the deep, superficial or perforator systems

• distribution: greater saphenous vein and tributaries

Etiology

• primary• main factor: inherited structural

weakness of valves• contributing factors: age, female,

OCP use, occupations requiring long hours of standing, pregnancy, obesity

• secondary• deep vein thrombosis

• congenital anomalies • arteriovenous fistula

Epidemiology

• 10 - 20% of the population

• >50% over the age of 50

Clinical Features

• History

• Ankle ache

• Fatigued legs

• swelling around the ankles

• aggravated by prolongued standing (end of day)

• P/E

• dilated and tortuous superfical veins

• Brodie-Trendelendberg test

• raise leg and compress saphenous vein at thigh; have patient stand; if vein fills quickly from top down then incompetent valves; use mulitple tourniquets to localize incompetent veins

Complications

• Usually benign natural history

• Most are cosmetic concerns

• recurrent superficial thrombophlebitis

• hemorrhage: external or subcutaneous

Investigations

• Duplex ultrasound to assess...

• reflux of blood at sapheno-femoral junction

Treatment

• Compression stocking therapy

• Saphenous vein stripping surgery • disabling symptoms

• Laser vein ablation

Chronic Venous Insufficiency

Definition

• chronic elevation of deep venous pressure and blood pooling in lower extremities

Etiology

• valvular incompetence usually due to a previous DVT many years ago

• chronic venous obstruction

• calf muscle pump dysfunction

Clinical Features

• ankle ache and edema - relieved by foot elevation

• hyperpigmentation (hemosiderin deposits)

• ulceration– shallow and irregular– above medial malleolus– painless

Investigations

• duplex ultrasound to assess

• Reflux at sapheno-femoral junction

• Deep system incompetence

• chronic occlusion from an old DVT/trauma

• Venogram

Treatment

• CONSERVATIVE

• compression stockings/layered compression bandages• leg elevation, avoid prolonged standing

• surgical• surgical ligation of perforators in region of ulcer, greater

saphenous vein stripping if incompetent

Superficial Thrombophlebitis

Definition

• inflammation secondary to acute thrombosis of a superficial vein usually the greater saphenous vein

Etiology

• varicose veins

• migratory superficial thrombophlebitis• hematologic: hypercoag state, polycythemia, thrombocytosis• neoplastic: occult malignancy (especially pancreas)• idiopathic

Clinical Features

• Usually involves GSV and its branches

• pain

• swelling along course of involved vein

• erythema

• warmth

Investigations

• Ultrasound to exclude associated DVT (5 - 10%)

Treatment

• CONSERVATIVE

• moist heat, compression bandages• anti-inflammatory and anti-platelet (ASA)