1. Present by Ri 張志富 Ri 戴君芙 Ri 陳婉瑜 Supervise by CR 劉治民
Endarterectomy
Present by Ri 張志富
Ri 戴君芙
Ri 陳婉瑜
Supervise by CR 劉治民
2018/11/11

2. Carotid artery stenosis
Atherosclerosis
TIA & stroke Tx
Antiplatelet (Aspirin)
Endarterectomy
Stent

3. Endarterectomy Indication (level I) Symptomatic, stenosis> 70 %
Asymptomatic, stenosis>60%
Guideline for carotid endarterectomy. A statement for healthcare professionals from a special writing group of the stroke council, American Heart Association. Stroke. 1998;

4. Preoperative evaluation
CAD
Common in P’t with carotid stenosis
AMI is leading mortality
Staged or combined approach
CEA first: cardiac morbidity ↑
Coronary first: stroke risk ↑
Combine in unstable CAD with severe carotid stenosis
Brown KR: Treatment of concomitant carotid and coronary artery disease:
Decision-making regarding surgical options. J Cardiovasc Surg (Torino) 44:395–399, 2003.

5. General Anesthesia Unpredictable BP response Induced hypertension:
10~20% above baseline
Increase brain perfusion
Myocardial ischemia

6. Regional Anesthesia 1 Allows continuous neurologic assessment
Reduced need for shunting
Greater stability of blood pressure and decreased vasopressor requirements
No absolute contradiction to regional anesthesia

7. Regional Anesthesia 2 Disadvantage
No pharmacologic cerebral protection
patient panic, or seizure
airway inadequate in conversion

8. General or regional ?
No differences in perioperative stroke or death rate
RA: fewer nonneurological, nonfatal complications
Papavasiliou AK, Magnadottir HB, Gonda T, et al: Clinical outcomes after carotid
endarterectomy: Comparison of the use of regional and general anesthetics.
J Neurosurg 92:291–296, 2000.

9. Intraoperative management of hemodynamic change
Bradycardia and Hypotension
Tachycardia
Hypertension
Cerebral intraoperative protection
Monitoring for the need of carotid shunt
Awake patients
EEG
Stump pressure
Cerebral oximetry
Others

10. Intraoperative management of hemodynamic change
Bradycardia and Hypotension
Carotid sinus manipulation
Vagus tone↑
Myocardial infarct, neurological deficits
Management
local anesthetics
temporary venous pacemakers
intravenous atropine
vasopressor

11. Local anesthetics 1% Lignocaine 2ml
Effect of lignocaine injection in carotid sinus on baroreceptor sensitivity during carotid endarterectomy
20 patients undergoing elective CEA
intraluminal stretch simulation of the carotid baroreceptors (rub test)
Effect of lignocaine injection in carotid sinus on baroreceptor sensitivity during carotid endarterectomy
Journal of Vascular Surgery Volume 39, Issue 6 , June 2004, Pages

12. Temporary venous pacemakers
37 balloon-assisted angioplasty and stent procedures
The pacemakers captured and maintained a rhythm in 23 (62%) of the 37 procedures and prevented symptomatic bradycardia and hypotension from occurring in all of the patients.
reduced the incidence of bradycardia and hypotension to only 3 (9%), as compared with the rate of 40 to 100% reported in the literature
Pacemakers were set to capture a heart rate decrease below 60 beats per minute
Prevention of carotid angioplasty-induced bradycardia and hypotension with temporary venous pacemakers. Neurosurgery Oct;49(4):814-20; discussion  

13. Intravenous atropine
treated selectively with atropine only after symptomatic bradycardia developed (nonprophylactic group)
routine prophylactic atropine administration (0.5–1 mg) before balloon inflation or stent deployment (prophylactic group).
Carotid angioplasty and stent-induced bradycardia and hypotension: Impact of prophylactic atropine administration and prior carotid endarterectomy. J Vasc Surg Jun;41(6)

14. Intraoperative management of hemodynamic change
Tachycardia
Stress, pain, catecholamine release
Underlying CAD
Myocardial infarct
Management
Short-acting βblocker (eg. esmolol)

15. A double-blind, randomised, controlled trial of 40 patients
Prevention of tachycardia with atenolol pretreatment for carotid endarterectomy under cervical plexus blockade.
A double-blind, randomised, controlled trial of 40 patients
20 for placebo; 20 for 50 mg of atenolol two hours prior to surgery
Tachycardia: 13/20 in the placebo group and 2/20 in the atenolol group (P < 0.01).
Tachycardia (heart rate greater than 90 beats per minute for more than three minutes)
Anaesth Intensive Care May;20(2):161-4.

16. Intraoperative management of hemodynamic change
Hypertension
Stress, pain, carotid body manipulation
Sympathetic tone ↑
Underlying CAD, Myocardial infarct, cerebral hemorrhage
Management
Nitroglycerin
Sodium nitroprusside
Crossclamping後血壓稍微上昇以便增加collateral circulation是可接受的
不過SBP>160要治療
Unclamping後HTN也要治療
Crossclamping後血壓會稍微上升以便增加collateral circulation是可接受的
但Hypertension: SBP>160

17. Cerebral intraoperative protection
Carotid shunt
Blood bypass from common to internal carotid artery
Complication:
Intimal flap arterial dissection
Plaque emboli or air embolism

18. Cerebral intraoperative protection
Monitoring
Awake patients
Under regional anesthesia
Eye movement, speech, grasping, consciousness

19. Cerebral intraoperative protection
Monitoring
EEG
Theta and delta waves or disorganized rhythm
Routine use of EEG was associated with apparent complete elimination of intraoperative strokes and less than 1% risk of perioperative strokes.
Carotid endarterectomy with routine electroencephalography and selective shunting: Influence of contralateral internal carotid artery occlusion and utility in prevention of perioperative strokes. J Vasc Surg Jun;35(6):
Comparison of simultaneous electroencephalographic and mental status monitoring during carotid endarterectomy with regional anesthesia
Journal of Vascular Surgery Volume 28, Issue 6 , December 1998, Pages

20. Cerebral intraoperative protection
Monitoring
Stump pressure
Circle of Willis ↔ ICA
Threshold: mmHg
Correlation of carotid artery stump pressure and neurologic changes during 474 carotid endarterectomies performed in awake patients.
Using 40 mm Hg systolic as a threshold, the need for shunting (15%) and the false-negative rate (1.0%) for SP in our series were equivalent to the results of EEG monitoring during CEA reported in the literature.
J Vasc Surg Oct;42(4):684-9.

21. Cerebral intraoperative protection
Monitoring
Cerebral oximetry
Regional cerebral oxygen saturation
Could not identify a threshold that can be used alone to predict the need for shunt placement
After San Raffaele Hospital Ethical Committee Approval and written informed consent were obtained, 50 ASA physical status II and III adults, aged 51 to 90 years and undergoing elective CEA with regional anesthesia, were prospectively studied.
A clinical evaluation of near-infrared cerebral oximetry in the awake patient to monitor cerebral perfusion during carotid endarterectomy. J Clin Anesth Sep;17(6):
P=0.01

22. Cerebral intraoperative protection
Others
Arterial blood pressure
Preoperative level or slightly higher
Normocapnia
Hypothermia
Volatile anesthetics and barbiturates
Avoid nitrous oxide: ↑postoperative myocardial ischemia
Induction drugs
Sodium thiopental
Propofol
Etomidate

23. SSEP The response of the sensory cortex
Able to detect subcortical sensory pathway ischemia
Decreased regional cerebral blood flow
(< 12 mL/100 g of brain tissue per minute)
No specific physiologic marker influenced amplitude
Not been definitively established
Canadian Journal of Anesthesia 51: (2004)

24. Transcranial Doppler (TCD)
Continuous measurement of blood flow
Detection of microembolic events
Peri-op: shunt function, malfunction, and incidence of emboli during shunt insertion
Post-op: early postoperative embolization, hyperperfusion syndrome
Technical difficulties
Outcome has not been reported
Annals of Vascular Surgery Inc. 2005,11 January

25. Postoperative Considerations
Postoperative stroke
Postoperative hypertension & hypotension
Hyperperfusion syndrome
Others

26. Postoperative stroke Cause Plaque emboli Platelet aggregates
Poor cerebral protection
Relative hypotension

27. Evaluation and treatment
Recovery room or intraoperative ultrasound
The optimal time to heparinize ?
Percutaneous transluminal carotid angioplasty with stenting
Thrombolytic therapy

28. Postoperative hypertension
Poorly controlled preoperative hypertension
Surgical denervation of the carotid sinus baroreceptors
General anesthesia > Regional anesthesia
Neurologic and cardiac complications

29. Postoperative hypotension
As frequently as hypertension
Carotid sinus baroreceptor hypersensitivity or reactivation
Regional anesthesia > General anesthesia
Myocardial and cerebral ischemia
Fluids and vasopressors

30. Hyperperfusion syndrome
Abrupt increase in blood flow with loss of autoregulation
Occurs several days after sugery
Moderate (20 to 44 %) increases in ipsilateral cerebral blood flow (by PWI)
Absence of increases in middle cerebral artery flow velocity (by TCD)

31. Risk Factors High-grade (>80%) carotid stenosis
Recent cerebral infarction
Reduced CBF or cerebral vasoreactivity
Severe postoperative hypertension

32. Symptoms and Signs Headache Focal motor seizures Focal neuralogic sign
Intracerebral hemorrhage
Brain edema

33. Treatment Strict control of postoperative hypertension
(SBP<150mmHg)
Intravenous labetalol, nitroprusside, and nitroglycerin
Most postoperative BP lability resolves in the first 24 hours

34. Others Nerve injury Wound hematoma Respiratory distress Infection
Parotitis

35. Prognosis Predictors of mortality Age Male sex Diabetes mellitus
Systemic hypertension
Cigarette smoking

36. References Miller: Miller's Anesthesia, 6th ed
Anesthesiology Clinics of North America Volume 22 • Number 2 • June 2004
James P Greelish, Emile R Mohler, III, Ronald M Fairman, for carotid endarterectomy (Cochrane review). The Cochrane Library. Issue 2 Oxford: Update Software; 2006.

37. Thank you for your attention