Vascular Flashcards
(124 cards)
1
Q
Atherosclerosis
Stage I
A
Fatty streak
- Endothelium damaged d/t hemodynamic shear stress, oxidize LDL destruction, chronic inflammatory responses, infection, & hypercoagulability → thrombosis
- Lipoproteins enter the arterial intimal layer via endothelium, become entrapped, & promote inflammation
2
Q
Atherosclerosis
Stage II
A
Fibrous plaque
- Oxidized lipid accumulation, inflammatory cells, proliferated smooth muscle cells, connective tissue fibers, & Ca2+ deposits
- Blood flow reduction → ischemia to vital organs & extremities → thrombus risk
3
Q
Atherosclerosis
Stage III
A
Advanced lesion
- Plaque w/ expanded lipid-rich necrotic core, Ca2+ accumulation, endothelial dysfunction
- Physical disruption to plaque protective cap (ulceration rupture) exposes blood to highly thrombogenic material promoting acute thrombus formation & vasospasm
- Complete occlusion possible → MI, stroke, ischemia
4
Q
Atherosclerosis Pathophysiology
A
Generalized, progressive, chronic inflammatory disorder
Fibrous intimal plaques associated w/ endothelial dysfunction develop in the arterial tree
Compromises blood flow to all organs & extremities lead to MI, stroke, & gangreneA
5
Q
Atherosclerosis Types
A
- Enlarged plaque reduces blood vessel lumen (ischemia or stable angina) → supply vs. demand & delayed periop MI
- Plaque rupture/ulceration, embolization, & thrombus formation (unstable angina, MI, TIA/CVA) → acute occlusion & early periop MI
- Media atrophy w/ arterial wall weakening (aneurysm dilation)
6
Q
What’s the most common site for atherosclerotic lesions?
A
42% aortoiliac peripheral 32% coronary 17% aortic arch branches 6% combined 3% mesenteric renal
7
Q
What medications to continue prior to vascular surgery?
A
Aspirin - antiplatelet ↑bleeding ↓GFR Statins - check liver function Diuretics - hypovolemia & electrolyte imbalance Ca2+ channel blockers - HoTN β blockers - bronchospasm ↓HR ↓BP
8
Q
What medications to discontinue prior to vascular surgery?
A
ACE inhibitors - HoTN w/ induction & coughing
Plavix (hold 7-8 days) antiplatelet ↑bleeding risk
Hypoglycemic drugs - hypoglycemia & lactic acidosis w/ Metformin
9
Q
Bare Metal Stent
A
Do NOT stop antiplatelet therapy < 1mos
↑MI risk
10
Q
Drug-Eluting Stent
A
Do NOT stop antiplatelet therapy < 6mos
11
Q
What’s the critical period for coronary stents to endothelialize?
A
6 weeks
12
Q
Recommendations to optimize patient prior to vascular surgery:
A
Smoking cessation
Weight loss & exercise
13
Q
Culprit Lesions
A
Vulnerable plaques w/ high thrombotic complication likelihood
Often located in coronary vessels w/o critical stenosis
14
Q
Demand Ischemia
A
Predominant cause periop MI
Supply/demand mismatch
15
Q
What predicts long-term mortality associated w/ vascular surgery?
A
Preop renal insufficiency or chronic renal disease → postop failure
16
Q
LE Peripheral Artery Disease
A
PAD or atherosclerotic occlusive LE disease
Insufficiency in LEs presenting w/ acute or chronic limb ischemia w/ occlusions distal to the inguinal ligament
17
Q
LE Peripheral Artery Disease Revascularization Associated Risks
A
Amputation, stroke, MI, death
Diabetes ↑risk
Assume atherosclerosis present in other areas - cardiac or cerebrovascular
18
Q
LE Peripheral Artery Disease
Revascularization Preop Considerations
A
Patients on antiplatelet & anticoagulants
- Ask when last taken
- Consult w/ surgical team about bleeding risk
- ASA, ticagrelor P2Y12 inhibitors, Rivaroxaban Xa inhibitor
- Clopidogrel 30% patients assumed pharmacogenetically resistant
Assess baseline S/S
β blockers & other chronic medications
19
Q
Peripheral Revascularization Indications
A
Acute ischemia d/t emboli, thrombus, or pseudoaneurysm postop (femoral line)
Chronic ischemia d/t atherosclerotic plaque progressively narrowing the vessels - claudication w/ eventual vessel thrombosis
20
Q
Acute Ischemia
A
Irreversible ischemia damage occurs w/in 4-6hrs
- Urgent thrombolytic therapy and/or angioplasty
- Arteriography
- Surgical intervention
21
Q
Chronic Ischemia
A
Surgery indicated when severe disabling claudication & critical limb ischemia (limb salvage)
22
Q
Peripheral Revascularization
Surgical Approach
A
Donor artery or vein w/ unobstructed blood flow exposed (common femoral, superficial femoral, or deep femoral) Target distal artery (recipient) exposed at or below the knee (dorsalis pedis or posterior tibial arteries) Tunnel created & graft passed Heparin IV (does not require reversal) Anastomosis constructed & arteriogram to conform adequate blood flow
23
Q
Peripheral Revascularization
Monitoring
A
Continuous EKG monitoring w/ ST analysis A-line CVP or PA catheter Foley to monitor I/Os (intravascular volume) Minimal blood loss & 3rd spacing Regional or general approach
24
Q
Peripheral Revascularization
Emergency Surgery Considerations
A
Monitor K+ levels Myoglobinemia Fasciotomy? Coagulation status EKG ischemia
25
Peripheral Revascularization
| Regional vs. General
Assess coagulopathy or anticoagulation therapy
Spinal best to avoid hematoma
No difference b/w regional & general based on cardiopulmonary complications
Regional 5x superior to general r/t graft occlusion complication rates
26
Graft Occlusion
Significant w/ general anesthesia approach in postop period
Hypercoagulable state
↓fibrinolysis → fibrinogen not broken down & clots form
↑Epi/NE/cortisol
Graft patency maintained w/ regional 2° ↑blood flow w/ sympathectomy
27
Peripheral Revascularization
| Anesthetic Management Intraop
AVOID vasopressors
Keep feet warm
Regional:
- L1 → L4 dermatomes
- T10 level adequate
- Epidural dosing 9-12mL including test dose (elderly patients require ↓dosing)
General:
- Balanced anesthetic w/ opioids, inhalational agent, N2O, & neuromuscular blocker
- Minimal opioids to facilitate extubation
- Deepen anesthetic during tunneling phase (3-5mcg/kg Fentanyl)
- Avoid hemodynamic extremes (β blockers often necessary)
28
Peripheral Revascularization
| Anesthetic Management Postop
```
Stress reduction & pain control
↑MI risk postop
Continuous EKG monitoring w/ ST analysis
Control HR & BP
Avoid anemia Hgb < 9g/dL
Frequent peripheral pulse checks
```
29
LE Endovascular
Less invasive procedure to deploy stent & improve artery patency
General, neuraxial, or MAC
Percutaneous procedures (often MAC sedation)
Open access (femoral stenosis) consider GA
30
Carotid Artery Disease
1° carotid artery disease cause = atherosclerosis
| Commonly occurs at the common carotid artery & internal/external carotid arteries
31
Carotid Artery Disease S/S
Fatal or debilitating stroke
TIA
Amaurosis fugax (transient monocular blindness attack)
Asymptomatic bruit
32
___ % strokes are ___
Approximately 87% strokes are ischemic (cerebral thrombosis or embolism)
< 20% strokes are preceded TIA
33
What disease accounts for up to 20% all strokes?
Extracranial atherosclerotic
34
Carotid Endarterectomy
| Indications
↓symptoms & prevent stroke
Most common peripheral vascular surgery
Symptomatic patients w/ 70-99% carotid stenosis
35
How to manage asymptomatic < 70% carotid stenosis?
```
Medical therapies (ASA)
Percutaneous angioplasty/stenting
```
36
Carotid Endarterectomy
| Preop Assessment
Ask about recent symptoms? MI or TIA
Optimize medical management
- β blocker, statins, antiplatelet therapy
- HTN control, restore intravascular volume, reset cerebral autoregulation
- Diabetes control
Coronary artery disease common (1st treat carotids d/t CABG bypass & impaired cerebral perfusion w/ carotid plaques)
- Assess coronary angiograms
37
SIGNIFICANT Coronary Artery Disease S/S
Unstable angina
Decompensated heart failure
Significant valve disease
38
Carotid Endarterectomy
| Anesthetic Management
```
Awake vs. GETA
Continue ASA & cardiac medications
Type & screen
EKG to monitor leads II & V - rhythm disturbances & ST segment changes
Cerebral oximeter
A-line
ACTs intraop
Central line rare
PIV x2
Fluid warmer
Lower body warmer
Arms tucked
```
39
Anterior Leads
V3 & V4
40
Inferior Leads
II, III, & AVF
41
Lateral Leads
I, AVL, V5, & V6
42
Septal Leads
V1 & V2
43
Carotid Endarterectomy
| Medications & Infusions
Phenylephrine 20-300mcg/min OR 0.15-0.75mcg/kg/min
Remifentanil 0.05-0.2mcg/kg/min
Clevidipine 1mg or 1-2mg/hr double every 90sec up to 32mg/hr
Nitroglycerin
β blockers (Labetalol 5mg, Esmolol 10mg or 100-300mcg/kg/min, Metoprolol 1mg)
Ephedrine 5-10mg
Heparin & Protamine
44
Carotid Endarterectomy
| MAP Goals
High-normal range especially during carotid clamping to increase collateral flow & prevent cerebral ischemia
Potential to induce HTN 10-20% above baseline during carotid clamping
Careful to prevent ↑MVO2
45
What response will be anticipated in response to carotid sinus manipulation? Why?
Bradycardia & HoTN d/t the baroreceptor reflex
46
How to treat sudden bradycardia & HoTN?
Stop surgical manipulation
| Ask surgeon to infiltrate the carotid bifurcation w/ 1% Lidocaine to prevent further episodes
47
Where are baroreceptors located?
Carotid sinuses & aortic arch
48
Carotid Endarterectomy
| Emergence
Assess neuro status - deficits require immediate attention (angiography, reoperation, or both)
HTN & tachycardia associated w/ emergence & extubation
- Consider β blocker or sedation to smooth emergence
↑pressure stresses the new suture lines
49
Awake Carotid Endarterectomy
Best way to monitor function
Patient has ball to squeeze Q5min checks
Minimal or NO sedation (Midazolam 0.5mg + Fentanyl 25mcg) to prevent interference w/ neurological assessment
Avoid Propofol
Consider Esmolol during induction/direct laryngoscopy to prevent sympathetic response
Patients potentially get hot & restless under the drapes
Uncover their legs
Prevent/treat HTN or HoTN
50
Awake Carotid Endarterectomy
| Regional Anesthesia
Cervical plexus block to C2-C4 dermatomes
↓shunts indication
Improved hemodynamic stability
Reduced costs (operative time & avoid cerebral oximetry sensors)
Requires patient cooperation*
51
Cervical Plexus Block
Identify posterior sternocleidomastoid border
Inject along the posterior border medial surface
Potential to block accessory nerve → trapezius muscle paralysis
52
GALA Trial
Multicenter RCT
Carotid endarterectomy under general or local anesthesia
Finding = anesthetic technique was not associated w/ any significant difference b/w general vs. local
53
Cerebral Autoregulation
Hypocapnia ↓CO2 → vasoconstriction ↓CBF
| Hypercapnia ↑CO2 → vasodilation ↑CBF
54
Carotid Artery Stump Pressure
| GOAL
> 50mmHg
Stump pressure represents the back-pressure resulting from collateral flow through the circle of Willis via contralateral carotid artery & vertebrobasilar system
55
NIRS
Near-infrared spectrophotometry
Non-invasive technique to continuously monitor regional cerebral O2 saturation
Approximates VENOUS blood O2 saturation
56
Carotid Endarterectomy
| Postop Complications
Thromboembolic & hemorrhage intracerebral events
HTN common d/t surgical carotid sinus baroreceptors denervation
HoTN common d/t baroreceptor hypersensitivity or reaction
Cerebral hyper-perfusion syndrome - abrupt ↑blood flow w/ loss autoregulation (S/S include headache, seizure, focal neurological deficits, cerebral edema, or intracerebral hemorrhage)
Cranial & cervical nerve dysfunction - RLN or SLN, hypoglossal, mandibular
- Bilateral RLN injury → bilateral vocal cord paralysis → life-threatening upper airway obstruction
Carotid body denervation - impaired ventilatory response to mild hypoxemia, central chemoreceptors impaired, worsened w/ opioid administration
Wound hematoma → requires immediate surgical intervention d/t airway impingement
57
Endovascular Carotid Artery Stenting
Percutaneous transluminal angioplasty & stenting
1. Femoral access
2. Aortic arch angiogram
3. Selective common carotid artery origin & angiogram cannulation
4. Guidewire placement into the external carotid
5. Place embolic protection device
6. Balloon angioplasty the lesion, advance stent delivery catheter across dilated lesion, deploy self-expanding stent, & stent balloon dilation
7. Complete angiogram
8. Access site management (hold pressure)
58
Aortic Diseases
Peripheral arteries - occlusive disease
Aorta & 1° branches
- Aneurysms
- Dissections
59
Aortic Aneurysm
Often medically managed
Dilation all 3 arterial layers
Occasionally produces symptoms d/t compression on surrounding areas
60
Aortic Aneurysm S/S
Asymptomatic
| Present w/ pain d/t compressing adjacent structures or vessels
61
Aortic Aneurysm Diagnosis
CXR
Echo
CT/MRI
Angiography
62
Aortic Dissection
Surgical EMERGENCY
Mortality up to 58%
Occurs when blood enters the medial layer (minutes to hours)
Initially presents w/ tear in the intima layer
63
Aortic Dissection S/S
Severe pain in the posterior chest or back pain
64
Aortic Dissection Diagnosis
Unstable - Echo
| Stable - CXR, CT/MRI, aortography, Echo
65
AAA
Abdominal aortic aneursym
Adventitial elastin degradation w/in vessels - genetic, biochemical, metabolic, infectious, mechanical, & hemodynamic factors
Concomitant aortoiliac occlusive disease present approximately 20-25% AAA patients
66
Abdominal Aortic Aneurysm
| Risk Factors
Elderly male
Smoker
Family history (genetic component)
Atherosclerosis & HTN
67
Abdominal Aortic Aneurysm S/S
Asymptomatic pulsatile abdominal mass
68
Abdominal Aortic Aneurysm
| Causes
Trauma
Mycotic infection (bacterial)
Syphilis
Marfan syndrome
69
AAA Repair
> 6cm diameter
Symptomatic < 5.5cm aneurysms
Expand > 0.5cm in 6mos period
5.5-5.9cm aneurysms are controversial, but often medically managed
70
Open Abdominal Aortic Reconstruction
More complex than CABG (no perfusionist or bypass pump)
Extensive incision & dissection
Clamping & unclamping the aorta & major branches → physiologic changes
Varying organ ischemia-reperfusion duration
Fluid shifts
Temperature fluctuations
Neurohumoral & inflammatory responses activated
71
What classifies AAA as relatively benign in terms rupture & expansion?
< 4cm diameter
72
LaPlace
↑diameter ↑wall tension (even when arterial pressure remains constant)
Systemic HTN enhances aneurysm enlargement
73
Ruptured AAA
Periop mortality ≈50%
74
Ruptured AAA Clinical Presentation
Classic triad:
1. Hypotension
2. Back pain
3. Pulsatile abdominal mass (not always present after aneurysm ruptures)
75
EVAR
Endovascular abdominal aortic aneurysm repair
Less invasive
Reduced morbidity & mortality
↓hospital LOS
Now most common technique to repair AAA
76
EVAR Anesthetic Considerations
MAC sedation w/ local or regional vs. general
Patient able to lay supine, co-morbidities, aneurysm complexity, & surgical urgency (full stomach → RSI)
Steering guide sheaths require L arm arterial cut down
Hemodynamic management
Preserve organ perfusion
Blood loss & intravascular volume
Temperature
Radiation safety (fluroscopy)
77
Spinal Cord Blood Supply
Extensive collateral circulation
Anterior artery x1 (supplies ≈75%)
- Artery of Adamkiewics AKA originates off the descending aorta b/w T9-T12 & supplies lower 2/3 spinal cord 1°
Posterior arteries x2 (supplies ≈25%)
78
Early EVAR Complications
```
Paraplegia
Stroke
Acute renal injury
Aneurysm rupture
Pelvic hematoma
```
79
Late EVAR Complications
```
Endoleaks
Aneurysm rupture
Device migration
Limb occlusion
Graft infection
```
80
Endoleaks Treatment
Balloon angioplasty to the proximal attachment site to obtain to desired seal via remodeling the stent-graft
Type II - transarterial embolization via iliac arteries or retrograde embolization through the superior mesenteric or inferior mesenteric arteries
Last resort = open surgical treatment
81
CIN
Contrast induced nephropathy
PRESERVE trial
1. Contrast load
2. Pre-existing kidney disease
Limit contrast load & ensure adequate hydration to ↓iodine-based dyes viscosity
82
Aortoiliac Occlusive Disease
Most common sites chronic atherosclerosis = infrarenal aorta & iliac arteries
Surgical intervention only when patients are symptomatic
83
AORTIC CROSS-CLAMP
| Factors to Consider
Pathophysiological changes are complex & depend on the following factors:
- Clamp level
- L ventricle status
- Degree periaortic collateralization
- Intravascular blood volume & distribution
- SNS activation
- Anesthetic drugs & techniques
- Heparinization
84
AORTIC CROSS-CLAMP
| Complications
Arterial HTN above the clamp & HoTN below the clamp
| ISCHEMIA → renal failure, hepatic ischemia, coagulopathy, bowel infarction, paraplegia
85
Aortic Cross-Clamp
| Left Ventricle
↑LV volume & pressure
Healthy heart no significant ventricular distention or dysfunction
Impaired or stiff heart w/ ↓myocardial contractility & coronary reserve → ventricular distention → acute LV dysfunction & myocardial ischemia
86
Baroreceptor response to aortic cross-clamp:
↑aortic pressure
| ↓HR/contractility/vascular tone
87
Aortic Cross-Clamp
| Metabolic Effects
↓O2 consumption 50%
Blood flow via tissues & organ below the aortic occlusion remains dependent on perfusion pressure
Independent from cardiac output
88
Physiological changes associated w/ aortic cross-clamp
```
HEMODYNAMIC
Acute ↑SVR ↓CO
↑arterial BP above the clamp
↓arterial BP below the clamp
↑segmental wall abnormalities
↑LV wall tension
↓ejection fraction
↑pulmonary occlusion pressure
↑central venous pressure & coronary blood flow
↓renal blood flow
METABOLIC
↓total body O2 consumption & CO2 production
↑mixed venous O2 saturation
↓total body O2 extraction
↑Epi/NE
Respiratory alkalosis & metabolic acidosis
```
89
Aortic Cross-Clamp
| Anesthetic Management
Vasodilators ↓afterload, wall stress, & MVO2 (Nitroprusside, NTG, Nicardipine, & Clevidipine)
Avoid long-acting medications
Perfusion to distal organs dependent on collateral circulation that originates proximal to the clamp or shunts
90
Aortic Cross-Clamp
| Placement
Higher the clamp level → more significant impact on perfusion to vital organs
Thoracic > supraceliac > infrarenal
91
Aortic Cross-Clamp
| Renal Effects
Aortic cross-clamping ABOVE the renal arteries ↓renal blood flow
Renal sympathetic blockade w/ epidural anesthesia to T6 level does not prevent or modify the severe impairment in renal perfusion & function
92
Renal failure after AAA repair
*Pre-existing renal dysfunction*
Ischemia during cross-clamp time
Thrombus or embolus interrupts RBF
Hypovolemia or HoTN
93
Renal Protection
Mannitol, loop diuretics, methylprednisolone, & low-dose Dopamine 1-3mcg/kg/min are used clinically to preserve renal function during aortic surgery
94
Mannitol
Renal protection
12.5g per 70kg
Improves renal cortical blood flow during infrarenal aortic cross-clamping & reduces ischemia-induced renal vascular endothelial cell edema & vascular congestion
*Also acts to scavenge free radicals, ↓renin secretion, & ↑renal prostaglandin synthesis
95
What patients are most vulnerable to the stress imposed on the cardiovascular system during aortic cross-clamping?
Patients w/ pre-existing impaired ventricular function & reduced coronary reserve
96
Pre-existing cardiac impaired ventricular function & reduced coronary reserve goals during aortic cross-clamping:
1. Reduce afterload (Nitroprusside or Clevidipine)
2. Maintain normal preload (IV fluids)
3. Maintain CO (inotropes & MAP goals)
97
How to prepare prior to aortic UNclamping
↓volatile anesthetics
↓vasodilators or discontinue
↑fluid administration (volume)
↑vasoconstrictors
Severe HoTN unresponsive to interventions notify surgeon to reapply the cross-clamp
Consider Mannitol or NaHCO3
97
Open AAA
| Anesthetic Considerations
```
Central line
PIV x2
A-line
Cross-matched blood
*Rapid blood loss possible
TEE
Cerebral oximetry
Esmolol, Nitroprusside, NTG, Clevidipine, Phenylephrine
Heparin 100-300u/kg + Protamine to reverse
Monitor ACTs
Postop pain consider epidural
Forced upper air warmer
Fluid warms
Do NOT warm the lower body during cross-clamp ↑injury to ischemia distal tissues d/t ↑metabolic demand (MVO2)
```
98
Aneurysm Hemodynamic Management
Avoid HTN d/t acute stress on the aneurysm → rupture
Maintain HR at or below baseline to prevent myocardial ischemia
Defer euvolemic resuscitation until aortic rupture surgically controlled ↑volume ↑pressure ↑bleeding
99
AAA
| Postop Considerations
Aggressively control HTN & tachycardia
Achieve hemodynamic, metabolic, & temperature homeostasis prior to extubation
LOS variable
Pain - epidural vs. PCA
100
AAA Complications
```
Myocardial infarction
Pneumonia (pulmonary edema)
Sepsis
Renal failure
↓tissue perfusion
Hypothermia
```
101
Thoracic Aortic Aneurysm
Associated w/ known genetic syndromes
- Marfan syndrome
- Ehlers-Danlos syndrome
- Bicuspid aortic valve
- Non-syndromic familial aortic dissection
102
Marfan Syndrome
Caused by mutations in the fibrillin-1 gene
103
Ehlers-Danlos Syndrome
Connective tissue disorder
| 19 different genetic manifestations
104
Bicuspid Aortic Valve
Most common congenital anomaly resulting in aortic dilation/dissection
Occurs in 1% population
105
TAA Repair Approach
Descending aorta - L posterolateral thoracotomy w/ one-lung ventilation
Ascending aorta - supine w/ median sternotomy
Full or partial cardiopulmonary bypass
106
Thoracic Aortic Aneurysm
| S/S
Typically reflects impingement on nearby structures
- Hoarseness d/t L RLN stretch
- Stridor d/t trachea compression
- Dysphagia d/t esophagus compression
- Dyspnea d/t lung compression
- Edema d/t superior vena cava compression
107
Thoracic Aortic Dissection
MI presentation
Acute, severe sharp pain in the anterior chest/neck or b/w the shoulder blades
Diminished or absent peripheral pulses
108
TAA Crawford Classification
| Type I
Aneurysm involving descending thoracic & upper abdominal aorta
109
TAA Crawford Classification
| Type II
Descending thoracic & most abdominal aorta
| *Most difficult to repair
110
TAA Crawford Classification
| Type III
Lower thoracic aorta & most abdominal aorta
| *Most difficult to repair
111
TAA Crawford Classification
| Type IV
Most or all abdominal aorta
112
DeBakey Classification
Dissection Aortic Aneurysms
Type I
Ascending aortic tear w/ dissection down entire aorta
113
DeBakey Classification
Dissection Aortic Aneurysms
Type II
Tear in the ascending aorta w/ dissection limited to only the ascending aorta
114
DeBakey Classification
Dissection Aortic Aneurysms
Type III
Tear in the proximal descending thoracic aorta w/ dissection from thoracic aorta to abdominal aorta
115
What cross-clamp timeframe correlates w/ minimal paraplegia risk?
< 30minutes
116
Artery or Adamkiewics
Anterior radicular artery
Exits the spinal cord at T9-T12
Supplies 1° blood flow to lower 2/3 spinal cord
117
Anterior Spinal Artery Syndrome
LE flaccid paralysis & bowel/bladder dysfunction
| Sensation & proprioception are spared
118
Spinal Cord Protection
Limit cross-clamp time < 30min
Distal aortic perfusion (extracorporeal support)
CSF drainage ↓spinal cord perfusion pressure (CSF pressure ↑10-15mmHg w/ cross-clamping)
Intrathecal papaverine
Mild hypothermia ↓O2 requirements 5% each 1°C
Do NOT actively warm the LE d/t ↑metabolic requirements, acidosis, & ischemic injury
Barbiturates & corticosteroids
Avoid hyperglycemia
119
When to extubate after aneurysm repair?
Patient fully awake
Consider extubating in ICU d/t intraop fluid shifts
Notify ICU team when paralytic not reversed
120
Ruptured Aneurysm
| EMERGENCY
Open or endovascular approach
Awake intubation vs. RSI w/ Etomidate 0.1mg/kg
14-16G PIVs
PRBCs
Rapid-infuser
Maintain normothermia
Dopamine, Epi/NE, Vasopressin
Place A-line, central line, & PA catheter after induction
TEE to assess ventricular function & filling pressures
121
Induction Medications
Fentanyl 10-15mcg/kg or Sufentanil 1-2mcg/kg
Etomidate 0.1-0.3mg/kg
Esmolol 100-500mcg/kg or Sodium nitroprusside 25-50mcg or Nitroglycerin 0.5-3mcg/kg
Lidocaine 1.5mg/kg
Rocuronium 1-2mg/kg
Hemodynamically stable patients Scopolamine 400mcg (amnesia)
122
Maintenance Medications
Narcotic/benzodiazepine
Low-dose volatile anesthetic Iso 0.3-0.5% or Sevo 0.5-1%
Epidural Morphine 2-4mg or Hydromorphone 0.5-0.8mg
Remifentanil 0.05-0.2mcg/kg/min
123
Cross-Clamp Medications
```
BEFORE:
- Mannitol 0.25-0.5g/kg & Furosemide 20-40mg
- Heparin 100-300units/kg
DURING:
- Nitroglycerin 0.5-2mcg/kg/min and/or 100mcg bolus
- Sodium nitroprusside 0.5-2mcg/kg/min
- Esmolol 50-300mcg/kg/min
AFTER:
- Volume
```
