Effect of Phenylephrine and Ephedrine on Cerebral (Tissue) Oxygen Saturation During Carotid Endarterectomy (PEPPER): A Randomized Controlled Trial. Fassaert Leonie M M,de Borst Gert J,Pennekamp Claire W A,Specken-Welleweerd Jantine C,Moll Frans L,van Klei Wilton A,Immink Rogier V Neurocritical care BACKGROUND:Short-acting vasopressor agents like phenylephrine or ephedrine can be used during carotid endarterectomy (CEA) to achieve adequate blood pressure (BP) to prevent periprocedural stroke by preserving the cerebral perfusion. Previous studies in healthy subjects showed that these vasopressors also affected the frontal lobe cerebral tissue oxygenation (rSO) with a decrease after administration of phenylephrine. This decrease is unwarranted in patients with jeopardized cerebral perfusion, like CEA patients. The study aimed to evaluate the impact of both phenylephrine and ephedrine on the rSO during CEA. METHODS:In this double-blinded randomized controlled trial, 29 patients with symptomatic carotid artery stenosis underwent CEA under volatile general anesthesia in a tertiary referral medical center. Patients were preoperative allocated randomly (1:1) for receiving either phenylephrine (50 µg; n = 14) or ephedrine (5 mg; n = 15) in case intraoperative hypotension occurred, defined as a decreased mean arterial pressure (MAP) ≥ 20% compared to (awake) baseline. Intraoperative MAP was measured by an intra-arterial cannula placed in the radial artery. After administration, the MAP, cardiac output (CO), heart rate (HR), stroke volume, and rSO both ipsilateral and contralateral were measured. The timeframe for data analysis was 120 s before, until 600 s after administration. RESULTS:Both phenylephrine (70 ± 9 to 101 ± 22 mmHg; p < 0.001; mean ± SD) and ephedrine (75 ± 11 mmHg to 122 ± 22 mmHg; p < 0.001) adequately restored MAP. After administration, HR did not change significantly over time, and CO increased 19% for both phenylephrine and ephedrine. rSO ipsilateral and contralateral did not change significantly after administration at 300 and 600 s for either phenylephrine or ephedrine (phenylephrine 73%, 73%, 73% and 73%, 73%, 74%; ephedrine 72%, 73%, 73% and 75%, 74%, 74%). CONCLUSIONS:Within this randomized prospective study, MAP correction by either phenylephrine or ephedrine showed to be equally effective in maintaining rSO in patients who underwent CEA. Clinical Trial Registration ClincalTrials.gov, NCT01451294. 10.1007/s12028-019-00749-w

Noninvasive cerebral oximetry during endovascular therapy for acute ischemic stroke: an observational study. Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism Implementing endovascular stroke care often impedes neurologic assessment in patients who need sedation or general anesthesia. Cerebral near-infrared spectroscopy (NIRS) may help physicians monitor cerebral tissue viability, but data in hyperacute stroke patients receiving endovascular treatment are sparse. In this observational study, the NIRS index regional oxygen saturation (rSO2) was measured noninvasively before, during, and after endovascular therapy via bilateral forehead NIRS optodes. During the study period, 63 patients were monitored with NIRS; 43 qualified for analysis. Before recanalization, 10 distinct rSO2 decreases occurred in 11 patients with respect to time to intubation. During recanalization, two kinds of unilateral rSO2 changes occurred in the affected hemisphere: small peaks throughout the treatment (n=14, 32.6%) and sustained increases immediately after recanalization (n=2, 4.7%). Lower area under the curve 10% below baseline was associated with better reperfusion status (thrombolysis in cerebral infarction ≥ 2b, P=0.009). At the end of the intervention, lower interhemispheric rSO2 difference predicted death within 90 days (P=0.037). After the intervention, higher rSO2 variability predicted poor outcome (modified Rankin scale > 3, P=0.032). Our findings suggest that bi-channel rSO2-NIRS has potential for guiding neuroanesthesia and predicting outcome. To better monitor local revascularization, an improved stroke-specific set-up in future studies is necessary. 10.1038/jcbfm.2015.181

Cerebral oxygen desaturation occurs frequently in patients with hypertension undergoing major abdominal surgery. Li Hongyi,Fu Qiaochu,Wu Zongfang,Sun Jiaoli,Manyande Anne,Yang Hui,Wang Peng Journal of clinical monitoring and computing Hypertensive patients are more likely to experience latent cerebral ischemia causing regional cerebral oxygen saturation (rSO) decrease during general anesthesia. The aim of this prospective observational study was to assess the incidence of decreased rSO in hypertensive patients undergoing major abdominal surgery and the perioperative factors affecting this change in rSO. A total of 41 hypertensive patients were enrolled and stratified according to their hypertension as controlled and uncontrolled. The intraoperative rSO and physiological data were routinely collected. The Mini-Mental State Exam (MMSE) was used to test cognitive function before surgery and after 4 days. Cerebral desaturation was defined as a decrease in rSO of more than 20% of the baseline value. There were 20 patients (49%) suffering intraoperative cerebral desaturation classified into cerebral desaturation group (group D) and those 21 without intraoperative desaturation classified into normal group (group N). The area under the curve below 90 and 80% of baseline (AUC and AUC) was lower in patients of group N (2752.4 ± 1453.3 min% and 0.0 min%) than in patients of group D (6264.9 ± 1832.3 min% and 4486.5 ± 1664.9 min%, P < 0.001). Comparing the two groups, the number of uncontrolled hypertensive individuals in group D (12/20) was significantly more than group N (4/21) (P = 0.007). A significant correlation was observed between relative decrease in MAP and relative decrease in rSO (r = 0.495, P < 0.001). Moreover, nine patients (45%) in group D occurred early postoperative cognitive function decline were more than three patients (14.3%) in group N (P = 0.031). This pilot study showed a large proportion of hypertensive patient experienced cerebral desaturation during major abdominal surgery and uncontrolled hypertension predisposed to this desaturation. NCT02147275 (registered at http://www.clinicaltrials.gov ). 10.1007/s10877-017-0024-0