Anesthetic considerations for intraoperative management of cerebrovascular disease in neurovascular surgical procedures

Improved rates of postoperative ischemia, completeness of aneurysm occlusion and neurological deficits in elective clipping of anterior circulation aneurysms over the past 20 years - association with technical improvements

BACKGROUND/PURPOSE

Several periprocedural adjuncts for elective surgical aneurysm treatment have been introduced over the last 20 years to increase safety and efficacy. Besides the introduction of IONM in the late-1990s, ICG-videoangiography (ICG-VAG) since the mid-2000s and intraoperative CT-angiography/-perfusion (iCT-A/-P) since the mid-2010s are available. We aimed to clarify whether the introduction of ICG-VAG and iCT-A/-P resulted in our department in a stepwise improvement in the rate of radiologically detected postoperative ischemia, complete aneurysm occlusion and postoperative new deficits.

METHODS

Patients undergoing microsurgical clip occlusion for unruptured anterior circulation aneurysms between 2000 and 2019 were included, with ICG-VAG since 2009 and iCT-A/-P (for selected cases) since 2016. Baseline characteristics and treatment-related morbidity/outcome focusing on differences between the three distinct cohorts (cohort-I: pre-ICG-VAG-era, cohort-II: ICG-VAG-era, cohort-III: ICG-VAG&iCT-A/-P-era) were analyzed.

RESULTS

1391 patients were enrolled (n = 74 were excluded), 779 patients were interventionally treated, 538 patients were surgically clipped by a specialized vascular team (cohort-I n = 167, cohort-II n = 284, cohort-III n = 87). Aneurysm size was larger in cohort-I (8.9 vs. 7.5/6.8 mm; p < 0.01) without differences concerning age (mean:55years), gender distribution (m: f = 1:2.6) and aneurysm location (MCA:61%, ICA:18%, ACA/AcomA:21%). There was a stepwise improvement in the rate of radiologically detected postoperative ischemia (16.2vs.12.0vs.8.0%; p = 0.161), complete aneurysm occlusion (68.3vs.83.6vs.91.0%; p < 0.01) and postoperative new deficits (10.8vs.7.7vs.5.7%; p = 0.335) from cohort-I to -III. After a mean follow-up of 12months, a median modified Rankin scale of 0 was achieved in all cohorts.

DISCUSSION

Associated with periprocedural technical achievements, surgical outcome in elective anterior circulation aneurysm surgery has improved in our service during the past 20 years.

Anesthesia for Neurosurgical Emergencies

Neurosurgical procedures are unique in that the best monitoring modality is the neurologic examination and the most important sign includes an intact mental status. Anesthesiologists play a vital role in medical management of neurosurgical emergencies. The authors discuss the important management strategies for these emergencies, including increased intracranial pressure and impending brain herniation, acute alteration of mental status, status epilepticus, and trauma to cervical spine. The key is to maintain cerebral and spinal cord perfusion pressure at all times to salvage neuronal recovery.

Prospective factors of temporary arterial occlusion during anterior communicating artery aneurysm repair

INTRODUCTION

This study was undertaken to determine variables that could predict, in the perioperative period of anterior communicating artery (ACom) aneurysms surgeries, the likelihood of postoperative sequelae and complications, after temporary arterial occlusion (TAO).

PATIENTS AND METHODS

In a universe of 32 patients submitted to ACom aneurysm repair in the last 7 years, 21 needed TAO intraoperatively, and had their data examined retrospectively.

RESULTS

Aneurysms larger than 7 mm were more likely to be treated with longer TAO time than small aneurysms, (p < 0.0001). There was no statistical correlation between time of occlusion and outcome. Age, Glasgow Coma Scale at initial evaluation, and Fisher scale at first CT scanning were independent factors of unfavorable outcome (p < 0.001). Meanwhile gender, tobacco addiction, obesity, arterial hypertension, dyslipidemia, location of TAO (A1 or A2), intraoperative rupture (IR) and the aneurysm size were not identified as independent prognostic factors.During follow-up period, two thirds of the patients had a favorable outcome, accomplishing normal daily life activities without major complications. Most patients developed clinical vasospasm (66.6 %), with 19 % of the patients harboring a severe disease. Delayed ischemic neurological deficit was observed in 28.5 %, without any statistical correlation to time of TAO or IR.

CONCLUSION

TAO during ACom aneurysm repair does not seem to add more morbidities to the procedure, and is not an independent prognostic factor.