Transcranial Doppler Monitoring after Carotid Endarterectomy
Section snippets
INTRODUCTION
The North American Symptomatic Carotid Endarterectomy Trial and European Carotid Surgery Trial have both shown that the risk of recurrent stroke is significantly reduced by carotid endarterectomy (CEA) in patients with severe (70–99%) internal carotid artery stenosis.1, 2 However, the overall benefits of CEA are dependent on perioperative morbidity and mortality. The pathogenesis of ischemic stroke during or shortly after surgery seems to be thromboembolic, but occlusion of the operated artery
METHODS
In our hospital approximately 200 CAEs are performed each years and for the present study 50% of these patients underwent TCD monitoring during the second hour after surgery. Patients were considered for inclusion in this study if they had a symptomatic or asymptomatic carotid artery stenosis and were to undergo CEA. Only patients in whom continuous TCD monitoring was possible were included in this prospective, nonrandomized cohort study. For logistical reasons, only the first two patients of
RESULTS
Postoperative TCD monitoring was well tolerated and could be performed in 102 patients without significant interruptions. The mean patient age was 67 years (range, 48–85 years), and 75 patients (74%) were male. Seventy-six of 102 patients (75%) had neurological symptoms prior to CEA, 26 patients were asymptomatic. During CEA, 25 patients (25%) were selectively treated with intraarterial shunting. A saphenous vein patch was used, in 45 patients (44%), and a Dacron patch (HemaCarotid,
DISCUSSION
In this study, the median number of TCD-detected microemboli during the second hour after CEA was low and decreased in most patients. Preprocedural patient characteristics and the use of a patch were not statistically significantly associated with the postoperative number of microemboli. Patients who were operated on without a shunt showed significantly more microemboli than patients treated with a shunt (p = 0.02). Three patients had a procedure-related cerebral complication (3%; 95% CI =
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Cited by (29)
Non-Invasive Cerebral Autoregulation Monitoring During Awake Carotid Endarterectomy Identifies Clinically Significant Brain Ischaemia
2020, European Journal of Vascular and Endovascular SurgeryImpact of external carotid artery occlusion at declamping of the external and common carotid arteries during carotid endarterectomy on development of new postoperative ischemic cerebral lesions
2019, Journal of Vascular SurgeryCitation Excerpt :Several investigators demonstrated that MESs that develop during exposure of the carotid arteries are significantly correlated with the postoperative development of new ischemic cerebral events, including ischemic lesions on DWI and neurologic deficits, immediately after CEA.6,8-10 Hemodynamic cerebral ischemia due to hemispheric cerebral hypoperfusion during ICA clamping also plays a significant role in the development of new ischemic cerebral events after CEA.22,23 Intraoperative EEG monitoring is the most widely used and best documented method for the detection of hemispheric cerebral hypoperfusion due to carotid clamping.21
Transcranial Doppler Ultrasound Detection of Microemboli as a Predictor of Cerebral Events in Patients with Symptomatic and Asymptomatic Carotid Disease: A Systematic Review and Meta-Analysis
2016, European Journal of Vascular and Endovascular SurgeryCitation Excerpt :The differences between subgroups were found to be significant with a chi-square value of less than 0.001 derived from the differences in log likelihood ratios. Eight studies, with a total of 1,414 individual patients, reported stroke or TIA as an outcome along with data for TCD recording of microembolic signals with high MES counts defined as positive.13,17–19,21,32,33,35 The sensitivity and specificity were 52.38 (95% CI 30.59–73.29) and 90.07 (95% CI 83.72–94.12, p < .05), respectively.
Carotid artery disease: stenting vs endarterectomy
2010, British Journal of AnaesthesiaCitation Excerpt :In contrast to conventional EEG, SSEPs monitor the cortex and the subcortical pathways in the internal capsule, an area not reflected in cortical EEG.82 Transcranial Doppler (TCD) can be used to measure blood flow velocity in the middle cerebral artery during CEA and followed as an indicator of CBF.83–90 Ischaemia is considered severe if mean velocity after clamping is 0–15% of pre-clamp value, mild if 16–40%, and absent if >40%.82
OCCLUSIVE CEREBROVASCULAR DISEASE
2010, Cottrell and Young's Neuroanesthesia: Fifth Edition