Dynamic cerebral autoregulation in acute lacunar and middle cerebral artery territory ischemic stroke

Background and Purpose - We addressed whether dynamic cerebral autoregulation (dCA) is affected in middle cerebral artery (MCA) territory (MCAS) and lacunar ischemic stroke (LS). Methods - Blood pressure (MAP) and MCA velocity (V) were measured in 10 patients with large MCAS (National Institutes of Health Stroke score, 17 +/- 2; mean +/- SEM), in 10 with LS (score, 9 +/- 1), and in 10 reference subjects. dCA was evaluated in time (delay of the MCA V-mean counter-regulation during changes in MAP) and frequency domains (cross-spectral MCA V-mean-to-MAP phase lead). Results - In reference subjects, latencies for MAP increments (5.3 +/- 0.5 seconds) and decrements (5.6 +/- 0.5 seconds) were comparable, and low frequency MCA V-mean-to-MAP phase lead was 56 +/- 5 and 59 +/- 5 degrees (left and right hemisphere). In MCAS, these latencies were 4.6 +/- 0.7 and 5.6 +/- 0.5 seconds in the nonischemic hemisphere and not detectable in the ischemic hemisphere. In the unaffected hemisphere, phase lead was 61 +/- 6 degrees versus 26 +/- 6 degrees on the ischemic side (P <0.05). In LS, no latency and smaller phase lead bilaterally (32 +/- 6 and 33 +/- 5 degrees) conformed to globally impaired dCA. Conclusions - In large MCAS infarcts, dynamic cerebral autoregulation was impaired in the affected hemisphere. In LS, dynamic cerebral autoregulation was impaired bilaterally, a finding consistent with the hypothesis of bilateral small vessel disease in patients with lacunar infarct

A decrease in blood pressure is associated with unfavorable outcome in patients undergoing thrombectomy under general anesthesia

Background Up to two-thirds of patients are either dependent or dead 3 €months after thrombectomy for acute ischemic stroke (AIS). Loss of cerebral autoregulation may render patients with AIS vulnerable to decreases in mean arterial pressure (MAP). Objective To determine whether a fall in MAP during intervention under general anesthesia (GA) affects func

Blood Pressure During Endovascular Treatment Under Conscious Sedation or Local Anesthesia

OBJECTIVE: To evaluate the role of blood pressure (BP) as mediator of the effect of conscious sedation (CS) compared to local anesthesia (LA) on functional outcome after endovascular treatment (EVT). METHODS: Patients treated in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry centers with CS or LA as preferred anesthetic approach during EVT for ischemic stroke were analyzed. First, we evaluated the effect of CS on area under the threshold (AUT), relative difference between baseline and lowest procedural mean arterial pressure (∆LMAP), and procedural BP trend, compared to LA. Second, we assessed the association between BP and functional outcome (modified Rankin Scale [mRS]) with multivariable regression. Lastly, we evaluated whether BP explained the effect of CS on mRS. RESULTS: In 440 patients with available BP data, patients treated under CS (n = 262) had larger AUTs (median 228 vs 23 mm Hg*min), larger ∆LMAP (median 16% vs 6%), and a more negative BP trend (-0.22 vs -0.08 mm Hg/min) compared to LA (n = 178). Larger ∆LMAP and AUTs were associated with worse mRS (adjusted common odds ratio [acOR] per 10% drop 0.87, 95% confidence interval [CI] 0.78-0.97, and acOR per 300 mm Hg*min 0.89, 95% CI 0.82-0.97). Patients treated under CS had worse mRS compared to LA (acOR 0.59, 95% CI 0.40-0.87) and this association remained when adjusting for ∆LMAP and AUT (acOR 0.62, 95% CI 0.42-0.92). CONCLUSIONS: Large BP drops are associated with worse functional outcome. However, BP drops do not explain the worse outcomes in the CS group

Cerebral autoregulation: from minutes to seconds

Bij patiënten met vaatschade door suikerziekte werken de regelmechanismen die de bloedtoevoer naar de hersenen zo constant mogelijk houden bij veranderingen in bloeddruk (cerebrale autoregulatie), direct na een beroerte en bij een extreem hoge bloeddruk veel minder goed. Bij deze patiënten is de bloedtoevoer naar de hersenen veel afhankelijker van de bloeddruk dan bij gezonde personen, concludeert Rogier Immink. De hersenen, die twee procent van het lichaamsgewicht uitmaken, verbruiken twintig procent van alle zuurstof die in een lichaam wordt opgenomen. Onderbreking van de bloedtoevoer resulteert binnen seconden in bewustzijnsverlies en binnen minuten tot schade

Noninvasive continuous arterial blood pressure monitoring with Nexfin (R)

Background: If invasive measurement of arterial blood pressure is not warranted, finger cuff technology can provide continuous and noninvasive monitoring. Finger and radial artery pressures differ; Nexfin (R) (BMEYE, Amsterdam, The Netherlands) measures finger arterial pressure and uses physiologic reconstruction methodologies to obtain values comparable to invasive pressures. Methods: Intra-arterial pressure (IAP) and noninvasive Nexfin arterial pressure (NAP) were measured in cardiothoracic surgery patients, because invasive pressures are available. NAP-IAP differences were analyzed during 30 min. Tracking was quantified by within-subject precision (SD of individual NAP-IAP differences) and correlation coefficients. The ranges of pressure change were quantified by within-subject variability (SD of individual averages of NAP and IAP). Accuracy and precision were expressed as group average +/- SD of the differences and considered acceptable when smaller than 5 +/- 8 mmHg, the Association for the Advancement of Medical Instrumentation criteria. Results: NAP and IAP were obtained in 50 (34-83 yr, 40 men) patients. For systolic, diastolic, mean arterial, and pulse pressure, median (25-75 percentiles) correlation coefficients were 0.96 (0.91-0.98), 0.93 (0.87-0.96), 0.96 (0.90-0.97), and 0.94 (0.85-0.98), respectively. Within-subject precisions were 4 +/- 2, 3 +/- 1, 3 +/- 2, and 3 +/- 2 mmHg, and within-subject variations 13 +/- 6, 6 +/- 3, 9 +/- 4, and 7 +/- 4 mmHg, indicating precision over a wide range of pressures. Group average +/- SD of the NAP-IAP differences were -1 +/- 7, 3 +/- 6, 2 +/- 6, and -3 +/- 4 mmHg, meeting criteria. Differences were not related to mean arterial pressure or heart rate. Conclusion: Arterial blood pressure can be measured non-invasively and continuously using physiologic pressure reconstruction. Changes in pressure can be followed and values are comparable to invasive monitorin

Noninvasive continuous arterial blood pressure monitoring with Nexfin (R)

Background: If invasive measurement of arterial blood pressure is not warranted, finger cuff technology can provide continuous and noninvasive monitoring. Finger and radial artery pressures differ; Nexfin (R) (BMEYE, Amsterdam, The Netherlands) measures finger arterial pressure and uses physiologic reconstruction methodologies to obtain values comparable to invasive pressures. Methods: Intra-arterial pressure (IAP) and noninvasive Nexfin arterial pressure (NAP) were measured in cardiothoracic surgery patients, because invasive pressures are available. NAP-IAP differences were analyzed during 30 min. Tracking was quantified by within-subject precision (SD of individual NAP-IAP differences) and correlation coefficients. The ranges of pressure change were quantified by within-subject variability (SD of individual averages of NAP and IAP). Accuracy and precision were expressed as group average +/- SD of the differences and considered acceptable when smaller than 5 +/- 8 mmHg, the Association for the Advancement of Medical Instrumentation criteria. Results: NAP and IAP were obtained in 50 (34-83 yr, 40 men) patients. For systolic, diastolic, mean arterial, and pulse pressure, median (25-75 percentiles) correlation coefficients were 0.96 (0.91-0.98), 0.93 (0.87-0.96), 0.96 (0.90-0.97), and 0.94 (0.85-0.98), respectively. Within-subject precisions were 4 +/- 2, 3 +/- 1, 3 +/- 2, and 3 +/- 2 mmHg, and within-subject variations 13 +/- 6, 6 +/- 3, 9 +/- 4, and 7 +/- 4 mmHg, indicating precision over a wide range of pressures. Group average +/- SD of the NAP-IAP differences were -1 +/- 7, 3 +/- 6, 2 +/- 6, and -3 +/- 4 mmHg, meeting criteria. Differences were not related to mean arterial pressure or heart rate. Conclusion: Arterial blood pressure can be measured non-invasively and continuously using physiologic pressure reconstruction. Changes in pressure can be followed and values are comparable to invasive monitorin

Noninvasive continuous arterial blood pressure monitoring with Nexfin (R)

Background: If invasive measurement of arterial blood pressure is not warranted, finger cuff technology can provide continuous and noninvasive monitoring. Finger and radial artery pressures differ; Nexfin (R) (BMEYE, Amsterdam, The Netherlands) measures finger arterial pressure and uses physiologic reconstruction methodologies to obtain values comparable to invasive pressures. Methods: Intra-arterial pressure (IAP) and noninvasive Nexfin arterial pressure (NAP) were measured in cardiothoracic surgery patients, because invasive pressures are available. NAP-IAP differences were analyzed during 30 min. Tracking was quantified by within-subject precision (SD of individual NAP-IAP differences) and correlation coefficients. The ranges of pressure change were quantified by within-subject variability (SD of individual averages of NAP and IAP). Accuracy and precision were expressed as group average +/- SD of the differences and considered acceptable when smaller than 5 +/- 8 mmHg, the Association for the Advancement of Medical Instrumentation criteria. Results: NAP and IAP were obtained in 50 (34-83 yr, 40 men) patients. For systolic, diastolic, mean arterial, and pulse pressure, median (25-75 percentiles) correlation coefficients were 0.96 (0.91-0.98), 0.93 (0.87-0.96), 0.96 (0.90-0.97), and 0.94 (0.85-0.98), respectively. Within-subject precisions were 4 +/- 2, 3 +/- 1, 3 +/- 2, and 3 +/- 2 mmHg, and within-subject variations 13 +/- 6, 6 +/- 3, 9 +/- 4, and 7 +/- 4 mmHg, indicating precision over a wide range of pressures. Group average +/- SD of the NAP-IAP differences were -1 +/- 7, 3 +/- 6, 2 +/- 6, and -3 +/- 4 mmHg, meeting criteria. Differences were not related to mean arterial pressure or heart rate. Conclusion: Arterial blood pressure can be measured non-invasively and continuously using physiologic pressure reconstruction. Changes in pressure can be followed and values are comparable to invasive monitorin