VASCULAR FINAL EXAM REVIEW Flashcards
What is an Aneurysm?
An aneurysm is a balloon-like bulge in an artery
When does An aneurysm occur?
When the pressure of blood passing through part of a weakened artery forces the vessel to bulge outward, forming somewhat ofa blister
If bulging stretches artery too far, What happens to the vessel?
vessel may burst
What are the layers of the artery from outer to inner?
Tunica Intima Internal Elastic Lamina Tunica Media External Elastic Lamina Tunica Externa
When does Aortic Dissection occur:
Aortic dissection occurs when the layers of the wall
of the aorta separate or are torn, allowing blood to flow between those layers and causing them to separate further
With aortic dissection, When the aortic wall separates, what occurs?
blood cannot flow freely, and the aortic wall may burst.
Anatomic types of dissecting aneurysms Type I
Intimal tear originates in ascending aorta
% of Debakey type I
70% of all cases
In type I Debakey Dissection involves (AVA)
Dissection involves
ascending aorta and arch
variable lengths of the descending thoracic and
abdominal aorta
Anatomic types of dissecting aneurysms• Debakey
Type II
Confined to ascending aorta
Anatomic types of dissecting aneurysms Type III Confined to
Descending thoracic aorta or extends into abdominal aorta and iliac arteries
Begins distal to the left subclavian artery
% of Debakey type III
20%
2 classifications of dissection
Stanford type A or B
Debakey Type I, II, III
Stanford Type A corresponds to Debakey
Type I and II
Stanford Type B corresponds to Debakey
Type III
Mechanisms for Aneurysm Formation (4 ways)
HADS
- HTN
- Atherosclerosis
- Syphilis
- Deceleration Injury
Aneurysms of the Ascending Thoracic Aorta: age affected
Usually middle aged
Signs & Symptoms
result of compression or stretching are a result of compression or stretching
Ascending Thoracic Aorta With aneurysm, compression of Trachea sx
Inspiratory stridor
Ascending Thoracic Aorta With aneurysm, compression of Esophagus sx
Dysphagia
With aneurysm, compression of • Laryngeal nerves sx
Hoarseness
Ascending Thoracic Aorta With aneurysm, compression of •Carotids sx
Occlusion
Ascending Thoracic Aorta With aneurysm, compression of •Coronary sx
Occlusion
Ascending Thoracic Aorta With aneurysm compression, can also get
Cardiac tamponade
Acute Aortic Regurgitation
Ascending Thoracic Aorta Diagnosis
- CXR
* Widening of mediastinum
Ascending Thoracic Aorta Treatment
M-TAFS
- Medical treatment
- Tight control of BP, HLD, and smoking cessation essential
- Avoid strenuous exercise and stimulants• Focus on ↓ expansion rate and avoiding evolution to dissection/rupture
- Surgical intervention
Replacement of Ascending Aorta with Vascular Graft: anesthesia consideration PREOP
Right radial A-line if the clamping is DISTAL to the LEFT subclavian artery)
Monitoring for patient having Ascending Aorta vascular graft
SSEP and EEG
Carotid Dopller
TEE
Replacement of Ascending Aorta with Vascular Graft:
Intra-op complications
CVA • Myocardial Infarction • Spinal cord injury
Replacement of Ascending Aorta with Vascular Graft: •POST OP Prevent
• HTN • Tachycardia • CNS Dysfunction
Aneurysm of the DESCENDING THORACIC AORTA
Classification and symptom
Debakey Type III
usually asymptomatic
Causes of DESCENDING TA
Deceleration injury
Myocardiac contusion
Treatment of DESCENDING TA
- Conservative medical management
* Surgical Intervention
Maximum thoracic aortic diameter
5.5 cm
Most Proximal part of descending aorta min and Max
5.5 and 6
Mid part of descending aorta min and max
3.5 and 4
Lower part of descending aorta min and max
3.5 and 9
Anesthesia consideration for DESCENDING : Monitoring
PA catheter
Right Radial A-line
Femoral A-line
Anesthesia consideration for DESCENDING : Monitoring
Induction double lumen (thoracotomy)
Anesthesia consideration for DESCENDING : POST OP
Neurologic Deficits
Artery of Adamkiewicz
Vessels supplying the spinal cord are
Adamkiewicz artery
Intercostal lumbar artery
Aorta
Radiculomedullary artery of Adamkiewicz
C3-C8
T3-T4
T11-T12 (Artery of Adamkiewicz)
Aortic blood supply to other organs
Basilar artery Vertebral Artery Ascending Cervical Artery Posterior spinal artery Subclavian artery Deep Certivcal artery Medial Sacral artery Radicular lumbosacral arteries Right lateral sacral artery Rignt internal iliac artery
Anterior Spinal Artery Syndrome: What causes
Cross-clamping thoracic aorta can result in ischemic
damage to spinal cord
Anterior Spinal Artery Syndrome: Frequency
40% in acute aortic dissection/rupture involving descending aorta
8% in elective thoracic aortic aneurysm repair
0.2% after elective infrarenal AAA repair
Anterior Spinal Artery Syndrome: Manifestations:
Flaccid paralysis LE, bowel/bladder dysfunction
• Sensation and proprioception spared!
Abdominal Aortic Aneurysms usually due to
• Usually due to atherosclerosis
Abdominal Aortic Aneurysms: Most common
Most common = infrarenal
AAA usually age and gender and family
- Usually male > 60 yrs old
* Familial tendency
AAA Signs & Symptoms
- Painless
- Pulsating abdominal mass
- Size dictates intervention
Size dictates intervention < 5cm
5% incidence of spont rupture
Size dictates intervention > 5cm
70% incidence of spont rupture
Ruptured AAA Classic triad (50%) BPH
- Hypotension
- Back pain
- Pulsatile abdominal mass
Most AAA rupture into
left retroperitoneum
AAA Anesthesia consideration : Requires consideration of monitoring of hemodynamic management that will be needed to control
hypertension during the period of aortic crossclamping:
AAA what is more important? •
Proper monitoring is more important than selection of anesthetic drugs in these patients.
Monitoring during procedures
• Systemic blood pressure
• Neurologic function
• Intravascular volume and planning the pharmacologic
interventions.
Thoracic Aortic Cross Clamping
• Cross clamping
- Severe hemodynamic + homeostatic disturbances
* Affects virtually all organ systems
Hemodynamics of cross clamping
• Hemodynamics: • ↑ systemic BP + SVR; no change in HR; Net ↓CO
With cross clamping what do you see with BP
Either ↓BF distal to clamp, ↑BF above level of occlusion
AAA cross clamping, Pharmacological interventions
• Vasodilators and what they do
Nicardipine
Nitroprusside
Nitroglycerin
ften reduce the clamp-induced decrease in cardiac output and ejection fraction
AAA, what happens to the Perfusion pressure distal to cross clamp
Perfusion pressure distal to cross clamp is ↓ and directly depends on proximal aortic pressure (pressure above the level of aortic clamping)
AAA What happens to blood flow to tissues distal to aortic occlusion
(kidneys, liver, spinal cord) occurs through collateral vessels or through a shunt
Aortic cross-clamping associated with
formation and release of hormonal factors (activation of SNS and RAAS)
and other mediators (prostaglandins, oxygen free
radicals, complement cascade).
Mediators release with cross clamping
These mediators may aggravate or blunt the harmful
effects of aortic cross-clamping and unclamping.
With cross clamping, injury to the spinal cord….
Injury to the spinal cord, lungs, kidneys, and abdominal
viscera is principally due to ischemia and subsequent
reperfusion injury caused by the aortic cross-clamp (localeffects) and/or the release of mediators from ischemic and reperfused tissues (distant effects).
Thoracic Aortic Unclamping: RESP
PVR, and cap membrane
Pulmonary damage 2° ↑PVR, ↑pulm cap
membrane permeability, development of pulmonary
edema
Thoracic Aortic unclamping MOA
may include pulmonary hypervolemia and the effects of various vasoactive mediators
Thoracic Aortic Unclamping:Hemodynamics:
SVR, BP, CO , LVEDP , myocardial BF
↓SVR + systemic BP
CO can ↑↓ or no ∆
↓ LVEDP, ↑myocardial BF
Causes of unclamping hypotension:
Volume and hypoxia
- Central hypovolemia caused by pooling of blood in reperfused tissues
- Hypoxia-mediated vasodilation, which causes an ↑ in vascular capacitance in tissues below the level of aortic clamping
Causes of unclamping hypotension: Vasodilation and hypotension may be further
aggravated by the transient increase in carbon dioxide release and oxygen consumption in these tissues following unclamping.
Cause of unclamping hypotension: vasoactive substances
Accumulation of vasoactive and myocardial depressant metabolites in these tissues
Unclamping and hypotension
Correction of metabolic acidosis does not significantly
influence the degree of hypotension following aortic
unclamping
Peripheral Vascular Diseases
• Chronic peripheral arterial occlusive disease
(atherosclerosis)
- Distal abdominal aorta or iliac arteries
- Femoral arteries
- Subclavian steal syndrome
- Coronary-subclavian steal syndrome
PVD acute
Acute peripheral arterial occlusive disease (embolism)
What are the systemic vasculitis? (TTT WSP)
- Takayasu’s arteritis
- Thromboangiitis obliterans
- Temporal arteritis
- Wegener’s granulomatosis
- Systemic vasculitis
- Polyarteritis nodosa
Other vascular syndromes
- Raynaud’s phenomenon
* Kawasaki disease
Peripheral Arterial Occlusive Disease (PAOD) aka
(atherosclerosis)
Peripheral Arterial Occlusive Disease (PAOD) risk factors
FOSDDOH
Risk factors same as ischemic heart disease: Family Hx Older age Smoking (doubled) DM Dyslipidemia Obesity HTN
• S/S of PAOD
Most reliable.
Intermittent claudication, pain at rest,
↓/absent arterial pulses = most reliable physical finding associated with PAD
Management of Anesthesia for Surgical
Revascularization
• Principal risk and how to prevent it ? who’s at increased risk
• Choice of anesthetic
• GETA if regional contraindicated (blood thinners, dementia, long surgical time)
• Inhalation agent-induced cardiac preconditioning might help
• Benefits of regional: ↑ graft BF, postoperative analgesia, ↓ activation of
coagulation system, and fewer postoperative respiratory complications
• Intraoperative heparinization is not a contraindication for epidural anesthesia
• Risk of bleeding ↑if on multiple blood thinners
myocardial ischemia
• Perioperative HR control c/BB ↓incidence
• ↑incidence CAD in pt population
Management of Anesthesia for Surgical
Revascularization
• Principal risk and how to prevent it ? who’s at increased risk
myocardial ischemia
• Perioperative HR control c/BB ↓incidence
• ↑incidence CAD in pt population
Management of Anesthesia for Surgical Revascularization: Do this test->
• Pharmacological stress test
Management of Anesthesia for Surgical Revascularization Choice of anesthetic
• GETA if regional contraindicated (examples)
• Intraoperative heparinization is not a contraindication for epidural anesthesia
• Risk of bleeding ↑if on multiple blood thinners
(blood thinners, dementia, long surgical time)
Management of Anesthesia for Surgical Revascularization Choice of anesthetic
• GETA if regional contraindicated (examples)
(blood thinners, dementia, long surgical time)
Management of Anesthesia for Surgical Revascularization: Benefits of regional
↑ graft BF
postoperative analgesia
↓ activation of coagulation system
Fewer postoperative respiratory complications
Management of Anesthesia for Surgical Revascularization: Benefits of regional
↑ graft BF
postoperative analgesia
↓ activation of coagulation system
Fewer postoperative respiratory complications
Management of Anesthesia for Surgical Revascularization: RISK OF BLEEDING
• Risk of bleeding ↑if on multiple blood thinners
Subclavian Steal Syndrome
•
Occlusion of innominate artery proximal to the origin of the vertebral artery ➔reversal of flow through the ipsilateral vertebral artery into distal subclavian artery
• Reversal of flow diverts blood flow from brain to supply the arm (subclavian steal syndrome)
Subclavian Steal Syndrome: EXPLAIN
ORR
Occlusion of innominate artery proximal to the origin of the vertebral artery ➔
Reversal of flow through the ipsilateral vertebral artery into distal subclavian artery➔
Reversal of flow diverts blood flow from brain to supply the arm (subclavian steal syndrome)
Subclavian Steal Syndrome: Symptoms
- Vertigo
- Ataxia
- Hemiplegia
- Syncope
Coronary-Subclavian Steal Syndrome
• Requires surgical bypass grafting
Rare complication of using the internal
mammary artery for coronary revascularization
Coronary-Subclavian Steal Syndrome : when does it occur?
Occurs when proximal stenosis in the left subclavian artery produces reversal of blood flow through the patent internal mammary artery graft
Coronary-Subclavian Steal Syndrome Symptoms
• Symptoms
• Angina pectoris
• Signs of central nervous system ischemia
• 20-mm Hg or more decrease in systolic blood
pressure in the ipsilateral arm
Coronary-Subclavian Steal Syndrome : Requires
• Requires surgical bypass grafting
Thromboangiitis Obliterans: what is it?
Inflammatory and occlusive disease of the arteries and veins
Thromboangiitis Obliterans: men vs women
• Greatest incidence in men
Thromboangiitis Obliterans• worsens condition
Smoking
Thromboangiitis Obliterans• Exacerbated by
cold and trauma
Thromboangiitis Obliterans: S/S
- Migratory thrombophlebitis
* Intermittent claudication
Thromboangiitis Obliterans Treatment:
- Stop smoking
- Avoid trauma
- Avoid cold
Thromboangiitis Obliterans Anesthesia Considerations
- Positioning
- Temperature
- No Aline
- Increase FiO2
- General
- Regional
Thromboangiitis Obliterans Anesthesia Considerations: NO _____
A-line
Thromboangiitis Obliterans Avoid this vasopressor
• Avoid epinephrine
Wegeners Granulomatosis
Formation of granulomas in the vicinity of inflammed
vessels-> This leads to infiltration bynecrotizing granulomas
Wegeners Granulomatosis Respiratory tract
- Nose
* Sinusitis
Wegeners Granulomatosis Respiratory tract• Larynx
- Narrowing of the glottic opening
* Destructive lesions of the epiglottis common
Wegeners Granulomatosis Respiratory tract• ALSO AFFECTS
Maxillary sinus
Hard palate
Wegeners Granulomatosis Pulmonary vessels
Lead to occlusion with V/Q mismatch
Wegeners Granulomatosis Upper trachea
- Pneumonia
* Hemoptysis
Wegeners Granulomatosis Signs & Symptoms
CV system
• Infarction of tips of digits
Wegeners Granulomatosis Signs & Symptoms• Nervous system
- CVA
- Peripheral neuropathy
- Skeletal muscle wasting
Wegeners Granulomatosis Kidneys
CHAP
Complete destruction of the renal glomeruli
• Hematuria
• Azotemia
• Progressive renal failure = mostcommon cause of death
Wegeners Granulomatosis Kidneys most common cause of death
Progressive renal Failure
Treatment of Wegeners Granulomatosis : Medication
Cyclophosphamide
Corticosteroids
Reaction to Cyclophosphamide (LHD)
- Leukopenia
- Hemolytic anemia
- Decreases activity of plasma cholinesterase
Wegeners Granulomatosis and Succ
Variable responses to Succinylcholine
PE Manifestations PANTA RTFH
Pleuritic Chest pain Accentuation of Pulmonary Valve closure sound (P2) Nonproductive Cough Tachypnea Acute dyspnea
Rales
Tachycardia
Fever
Hemoptysis
Pathophysiology of PE (BID PATARAA)
Bronchospasm Increase in alveolar dead space Decrease in surfactant Pulmonary Compliance decreases Atelectasis Tissue Necrosis Acute increase in PVR RV failure occur Arterial hypoxemia Airway resistance increases
PE ECG manifestations
S1
Q3
T3
Deep, Precordial T-wave inversions
PE signs during Anesthesia HATBD
Hypotension Arterial Hypoxemia Tachycardia Bronchospasm Decrease in ETCO2