Vascular Emergencies Scott M Surowiec, MD Assistant Professor of Surgery Upstate Vascular and Crouse Hospital September 29, 2015 Introduction • Main vascular emergencies include • Ruptured Abdominal Aortic Aneurysm (rAAA) • Aortic Dissection • Acute Limb Ischemia • Embolism from Cardiac Source Most Common • Thrombosis of Preexisting Diseased Vessel • Thrombosis of Limb Bypass Graft • Thrombosed Dialysis Access • Native Arteriovenous Fistula • Clotted Arteriovenous Graft • Symptomatic Carotid Artery Stenosis • Symptoms range from Stroke to Amaurosis Fugax, Hemiparesis, or Speech Deficit Episodes • Vascular Trauma Abdominal Aortic Aneurysm • Abdominal Aorta with Max Diameter > 3.0 cm • Most often affect the segment of aorta below the renal arteries • Most AAA produce no symptoms • Ruptured AAA – aortic rupture is due to the weakening of the aortic wall leading to tearing of the aortic wall, allowing blood to escape outside the confines of the aorta • Symptomatic (non-ruptured) AAA – refers to any number of symptoms (eg abdominal/back/flank pain, limb ischemia) that can be attributed to the aneurysm. The presence of symptoms increases the risk for rupture Abdominal Aortic Aneurysm • PreOp Factors Predict 100% rAAA Mortality • Age > 76 (odds ratio 2.1) • PreOp Creatinine >2 mg/dL (odds ratio 3.7) • Blood pH < 7.2 (odds ratio 2.6) • SBP at any point < 70 mm Hg (odds ratio 2.7) 303 Ruptured AAA Patients • Harborview Medical Center (Seattle) • 2002 – 2013 • 30 day mortality • 54% for open repair • 22% for endovascular repair rAAA Initial Management • Classic signs and symptoms of rupture: • Hypotension • Flank/back pain • Pulsatile Mass • Hemodynamically Unstable Patients, Candidate for RepairStraight to OR • Perhaps with stop in CT scanner if endovascular repair possible • Hemodynamically Stable, Symptomatic (non-ruptured) ICU monitoring rAAA: Initial Mangement • 2 Large Bore peripheral IV • Permissive Hypotension • Indirect evidence from Trauma Population, one observational study • Allowing relatively low SBP of 80-100 may prevent further tearing of the aorta and limit blood loss • Pain Control • Keep patient comfortable, but consciousness should be maintained • In patients who remain severely hypertensive (non-ruptured AAA), short-acting IV beta-blockers (eg. esmolol) can be used • Lab Studies • 10 Units PRBC should be available for OR • FFP, PF24 rAAA • In general, without repair, rAAA is uniformly fatal • Death occurs usually within hours and certainly within a week of rupture • Some patients may be too high risk due to underlying comorbidities that comfort care is appropriate • HD unstable patients go straight to OR • HD stable patients get CT of Abdomen rAAA: Decision for Patient Transfer • rAAA patients should be treated at a facility where surgical expertise and/or the perioperative resources necessary for major aortic surgery are available • For patients who present to a facility where these are not available, transfer to a vascular center is appropriate • The number of qualified surgeons in the community experienced with open repair of ruptured AAA is declining • If transfer is chosen, the patient and their family should be informed of the potential risk for deterioration during transfer Institutional Factors for EVAR • Systems must be in place to support the endeavor: • Appropriate Hospital Personnel • Rapid Availablilty of High Quality CT • Availability of Trained support staff (RN, Scrub Tech, Radiology Tech, Anesthesia) • Stock of Available Endovascular Prosthesis • Available Vascular Surgeon trained in endovascular techniques rAAA: Decision for Comfort Care • Some patients may refuse AAA repair • Some patients already refused (ask them) • Factors associated with Increased mortality following open rAAA repair: • SBP < 80 • Age > 80 • Cardiac Arrest • Loss of Consciousness • Creatinine > 1.3 • Heart Disease • Female Gender • Hgb < 9.0 on admission • Patients who will not undergo repair are kept pain-free and allowed to expire (avg time to death 7 hours; another study median survival 2.2 hours) rAAA: Summary • Get to Major Vascular Center ASAP • Bring films (CT on CD) if possible (Endovascular Repair) • Permissive Hypotension (SBP 80-100) is OK • Ask patient if they knew about aneurysm and if they want it repaired • 2 large bore IV • Type and Cross 10 Units PRBC • 50/50 survival If patient makes it to Vascular Center • Overall 85% mortality (role of screening high risk populations) Aortic Dissection • Relatively uncommon (65% men, mean age 63) • Catastrophic • Severe chest pain and acute hemodynamic compromise • Early and accurate diagnosis and treatment are critical to survival • Primary event is a tear in the aortic intima • Degeneration of the aortic media • Blood passes into the aortic media through the tear Aortic Dissection: Clinical Manifestations • Severe, sharp, “tearing” posterior chest of back pain, or anterior chest pain • Painless dissection is relatively uncommon • Syncope is associated with worse outcome (due to cardiac tamponade and stroke) • Hypertension more common in those with a distal (type B) Dissection • Pulse deficit present in 19-30% of Type A Dissections and 9-21% of Type B Dissections Aortic Dissection • Propagation of the dissection can occur both proximal and distal • Can lead to: • Coronary Ischemia • Stroke • Spinal Ischemia • Visceral Ischemia • Aortic Regurgitation • Cardiac Tamponade Aortic Dissection • Risk Factors • Hypertension • Atherosclerosis • Aortic Aneurysm (esp Ascending Aorta) • Inflammatory diseases that cause a vasculitis • Giant cell arteritis • Takayasu arteritis • Rheumatoid arthritis • Syphilitic aortitis • Collagen Disorders • Marfan Syndrome • Ehlers-Danlos Syndrome • Others (bicuspid aortic valve, aortic coarct, CABG, trauma, crack cocaine) Aortic Dissection: Types • Stanford Type A • Intimal Tear Without Dissection: Involves Hematoma Ascending Aorta • Aortic Intramural Hematoma • Stanford Type B • Penetrating Atherosclerotic Dissection: All other Ulcer dissections • Ascending dissections are twice as common as Descending Dissections Aortic Dissection: Diagnosis • Abrupt onset of pain with sharp, tearing, or ripping character • Mediastinal widening on CXR • A variation in pulse and/or BP between arms • CTA of Chest most commonly used study Aortic Dissection: Chest CTA Aortic Dissection: Acute Management • Pain Control (morphine) • BP Management (get BP to 100-120) • IV Beta Blocker (esmolol) to get HR < 60 ; SBP < 120 • Avoid Hydralazine as it can increase aortic shear stress • Evaluate hypotension (blood loss, tamponade, valve dysfunction, LV Systolic Dysfunction • If unstablebedside TEE • If stableCTA Chest Abd Pelvis Aortic Dissection: Definitive Management • Type A Dissection: Emergent OR • Concurrent hemorrhagic stroke relative contraindication • Type B Dissection: Medical Treatment with OR for complications • Spontaneous healing of the dissection is uncommon • Occlusion of major branch vessel • Persistent hypertension or pain • Propagation of dissection • Aneurysmal Expansion • Aortic Rupture Acute Limb Ischemia: Etiology • Arterial Emboli • Paradoxical Embolism • Arterial Thrombosis • Arterial Trauma Acute Limb Ischemia: Risk Factors • Atrial Fibrillation • Recent Myocardial Infarction • Aortic Atherosclerosis • Large vessel aneurysm disease • Prior lower extremity revascularization • Risk factors for aortic dissectin • Arterial trauma • DVT (paradoxical embolism) Acute Limb Ischemia: Presentation • Without underlying vascular disease: • No collaterals • Rapid onset of symptoms • 6 “P’s”: paresthesia, pain, pallor, pulselessness, poikilothermia, paralysis • With occlusive vascular disease: • Slower onset • Gradually increasing symptoms in a patient with a history of chronic ischemia is indicative of arterial thrombosis • Sudden return of symptoms similar to those prior to revascularization Acute Limb Ischemia: Blue Toe Syndrome • Small vessel occlusion • Embolic occlusion of digital arteries • Sudden appearance of cool, painful, cyanotic toe(s) • Identification and eradication of embolic source • Presence of strong pedal pulses • Bilateral disease indicates disease above aortic bifurcation Acute Limb Ischemia: Clinical Categories • Viable Limb • Irreversible Ischemia • No sensory loss or muscle weakness • Major tissue loss • Arterial and venous doppler signals are audible • Permanent nerve damage • Marginally viable • No arterial or venous doppler • No or minimal sensory loss signals • No muscle weakness • Will require major amputation • Arterial doppler signals frequently inaudible • Revascularization may be • Salvageable if treated promptly needed to permit healing of • Immediately Threatened amputation • Have sensory loss • Rest pain • Muscle Weakness • Salvageable with immediate revascularization Acute Limb Ischemia: Initial Management • Anticoagulation • Immediate intravenous heparin bolus followed by a continuous heparin infusion • Prevents further propagation of thrombus and inhibits distal thrombosis • Time is crucial • Do not delay while waiting for diagnostic procedures to be performed Acute Limb Ischemia: Definitive Management • Viable Extremity: • Intraarterial Thrombolysis • Embolectomy for proximal embolus • Threatened Extremity • Emergent surgical revascularization • Majority of these patients have had an embolic event • The time to successfully dissolve embolus is usually too long • Fasciotomy may be required to prevent compartment syndrome • Oral anticoagulation used to prevent recurrent embolism • Nonviable Extremity • Prompt Amputation