Exam 3 Vascular Surgery Flashcards
What coexisting diseases are seen in vascular surgery patients?
diabetes
HTN
smoking
Renal impairment
pulmonary disease
systemic atherosclerosis
coronary artery disease
What is the leading cause of perioperative death mortality at the time of vascular surgery?
coronary artery disease
How do you recognize a patient is having an MI under anesthesia?
arrhythmias
ST elevation
Hypotension
What is the pathology of atherosclerosis?
generalized, progressive, chronic inflammatory disorder of the arterial tree with development of fibrous intimal plaque associated with endothelial dysfunction
What are the three stages of atherosclerosis?
Stage 1: fatty streak
Stage 2: fibrous plaque
stage 3: advanced lesion
Describe stage 1 of atherosclerosis?
endothelium is damaged due to hemodynamic shear stress, oxidized LDL destruction, chronic inflammatory responses, infection, hypercoagulopathy resulting in thrombosis
What is stage 2 of atherosclerosis?
composed of oxidized lipid accumulation, inflammatory cells, proliferated smooth muscle cells, connective tissue fibers, and calcium deposits
blood flow reduction- ischemia to vital organs and extremities, thrombus risk
What is stage 3 of atherosclerosis?
plaque with expanded lipid rich necrotic ore, calcium accumulation, endothelial dysfunction
physical disruption of plaque’s protective cap (rupture or ulceration), exposes blood to highly thrombogenic material promoting acute thrombus formation and vasospasm
complete occlusion possible (stroke, MI, ischemia)
What three types of atherosclerosis cause morbidity?
enlarged plaque reduces lumen of blood vessel (limb ischemia, stable angina)
plaque rupture/ ulceration, embolization, thrombus formation (unstable angina, MI, TIA, CVA)
Atrophy of media with arterial wall weakening (aneurysm dilation)
What are the most common sites for atherosclerotic lesions?
aortoiliac peripheral 42%
coronary 32%
Arch branches 17%
combined
mesenteric/ renal
vessel bifurications, d/t shear forces
What were the goals of ACC and AHA pre-operative evaluation guidelines?
to optimize patient for surgery
best possible quality care and outcome for the patient
information obtained should be used for both the perioperative period and to inform the long term treatment plan
What are the pre-operative evaluation guidelines?
clinical history (clinical risk factors, exercise tolerance)
supplemental evaluation
perioperative therapy
surgical procedure (low, intermediate, high risk)
What is the critical period of coronary stenting?
6 weeks to endothelialize
bare mental stent- don’t stop <1 year, DES <6months
stopped too soon= MI risk
What dual therapy is need after stenting?
aspirin and plavix
What cardiac function testing is needed prior to vascular surgery? (4)
exercise/pharmacologic stress test
ECHO
Myocardial ischemia, previous MI, valve dysfunction, heart failure
duplex imaging of carotid arteries or angiography
What are pulmonary complications following vascular surgery?
atelectasis, pneumonia, respiratory failure, exacerbation of underlying chronic disease
How can pulmonary complications after vascular surgery be avoided?
incentive spirometry, steroids, regional anesthesia, antibiotics, CPAP
What predicts long term mortality in patients with symptomatic lower extremity arterial occlusive disease?
chronic renal disease
How can renal complications be avoided?
dye use, beta blockers, statins, volume status, perfusion pressures
What is lower extremity peripheral artery disease?
insufficiency in lower extremities presenting with acute or chronic limb ischemia with occlusions distal to the inguinal ligament
What disease population is at higher risk with LE PAD?
DM
What antiplatelet and anticoagulants may be used in LE PAD?
ASA, ticagrelor (P2Y12 inhibitors), rivaroxaban (Xa inhibitors)
When is surgery indications for peripheral revascularization?
severe disabling claudication
critical limb ischemia (limb salvage)
What are indications for peripheral revascularization?
acute ischemia
irreversible damage
chronic ischemia
Describe the traditional surgical approach to peripheral revascularization
donor and recipient arteries exposed, tunnel created and graft is passed
graft may be saphenous vein or prosthesis
heparin IV administered
anastomosis constructed
arteriogram to confirm adequate flow
Why is graft occlusion significant withe general anesthesia then RA?
a. Because GETA causes hypercoagulable state, fibrinolysis decreases after GA (therefore, fibrinogen do not break down=clots), NE/E/cortisol release, patency of graft maintained with RA s/c to increase blood flow with sympathectomy