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Carlson AP, Jones T, Zhu Y, Desai M, Alsarah A, Shuttleworth CW. Oxygen-Based Autoregulation Indices Associated with Clinical Outcomes and Spreading Depolarization in Aneurysmal Subarachnoid Hemorrhage. Neurocrit Care 2024:10.1007/s12028-024-02088-x. [PMID: 39192101 DOI: 10.1007/s12028-024-02088-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Accepted: 07/29/2024] [Indexed: 08/29/2024]
Abstract
BACKGROUND Impairment in cerebral autoregulation has been proposed as a potentially targetable factor in patients with aneurysmal subarachnoid hemorrhage (aSAH); however, there are different continuous measures that can be used to calculate the state of autoregulation. In addition, it has previously been proposed that there may be an association of impaired autoregulation with the occurrence of spreading depolarization (SD) events. METHODS Study participants with invasive multimodal monitoring and aSAH were enrolled in an observational study. Autoregulation indices were prospectively calculated from this database as a 10 s moving correlation coefficient between various cerebral blood flow (CBF) surrogates and mean arterial pressure (MAP). In study participants with subdural electrocorticography (ECoG) monitoring, SD was also scored. Associations between clinical outcomes using the modified Rankin scale and occurrence of either isolated or clustered SD were assessed. RESULTS A total of 320 study participants were included, 47 of whom also had ECoG SD monitoring. As expected, baseline severity factors, such as modified Fisher scale score and World Federation of Neurosurgical Societies scale grade, were strongly associated with the clinical outcome. SD probability was related to blood pressure in a triphasic pattern, with a linear increase in probability below MAP of ~ 100 mm Hg. Multiple autoregulation indices were available for review based on moving correlations between mean arterial pressure (MAP) and various surrogates of cerebral blood flow (CBF). We calculated the pressure reactivity (PRx) using two different sources for intracranial pressure (ICP). We calculated the oxygen reactivity (ORx) using the partial pressure of brain tissue oxygen (PbtO2) from the Licox probe. We calculated the cerebral blood flow reactivity (CBFRx) using perfusion measurements from the Bowman perfusion probe. Finally, we calculated the cerebral oxygen saturation reactivity (OSRx) using regional cerebral oxygen saturation measured by near-infrared spectroscopy from the INVOS sensors. Only worse ORx and OSRx were associated with worse clinical outcomes. Both ORx and OSRx also were found to increase in the hour prior to SD for both sporadic and clustered SD. CONCLUSIONS Impairment in autoregulation in aSAH is associated with worse clinical outcomes and occurrence of SD when using ORx and OSRx. Impaired autoregulation precedes SD occurrence. Targeting the optimal MAP or cerebral perfusion pressure in patients with aSAH should use ORx and/or OSRx as the input function rather than intracranial pressure.
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Affiliation(s)
- Andrew P Carlson
- Department of Neurosurgery, University of Virginia School of Medicine, Charlottesville, VA, USA.
- Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, NM, USA.
| | - Thomas Jones
- Department of Psychiatry, University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Yiliang Zhu
- Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Masoom Desai
- Department of Neurology, University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Ali Alsarah
- Department of Neurology, Harvard University, Boston, MA, USA
| | - C William Shuttleworth
- Department of Neuroscience, University of New Mexico School of Medicine, Albuquerque, NM, USA
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Carlson AP, Jones T, Zhu Y, Desai M, Alsarah A, Shuttleworth CW. Oxygen-based autoregulation indices associated with clinical outcomes and spreading depolarization in aSAH. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.05.17.24307563. [PMID: 38798620 PMCID: PMC11118627 DOI: 10.1101/2024.05.17.24307563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Background Impairment in cerebral autoregulation has been proposed as a potentially targetable factor in patients with aneurysmal subarachnoid hemorrhage (aSAH), however there are different continuous measures that can be used to calculate the state of autoregulation. In addition, it has previously been proposed that there may be an association of impaired autoregulation with the occurrence of spreading depolarization (SD) events. Methods Subjects with invasive multimodal monitoring and aSAH were enrolled in an observational study. Autoregulation indices were prospectively calculated from this database as a 10 second moving correlation coefficient between various cerebral blood flow (CBF) surrogates and mean arterial pressure (MAP). In subjects with subdural ECoG (electrocorticography) monitoring, SD was also scored. Associations between clinical outcomes using the mRS (modified Rankin Scale) and occurrence of either isolated or clustered SD was assessed. Results 320 subjects were included, 47 of whom also had ECoG SD monitoring. As expected, baseline severity factors such as mFS and WFNS (World Federation of Neurosurgical Societies scale) were strongly associated with the clinical outcome. SD probability was related to blood pressure in a triphasic pattern with a linear increase in probability below MAP of ∼100mmHg.Autoregulation indices were available for intracranial pressure (ICP) measurements (PRx), PbtO2 from Licox (ORx), perfusion from the Bowman perfusion probe (CBFRx), and cerebral oxygen saturation measured by near infrared spectroscopy (OSRx). Only worse ORx and OSRx were associated with worse clinical outcomes. ORx and OSRx also were found to both increase in the hour prior to SD for both sporadic and clustered SD. Conclusions Impairment in autoregulation in aSAH is associated with worse clinical outcomes and occurrence of SD when using ORx and OSRx. Impaired autoregulation precedes SD occurrence. Targeting the optimal MAP or cerebral perfusion pressure in patients with aSAH should use ORx and/or OSRx as the input function rather than intracranial pressure.
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You F, Tang WJ, Zhang C, Ye MQ, Fang XG, Zhou YF. Whole-brain CT Perfusion at Admission and During Delayed Time-window Detects the Delayed Cerebral Ischemia in Patients with Aneurysmal Subarachnoid Hemorrhage. Curr Med Sci 2023; 43:409-416. [PMID: 36864249 DOI: 10.1007/s11596-023-2703-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 10/23/2022] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To evaluate the utility of computed tomography perfusion (CTP) both at admission and during delayed cerebral ischemia time-window (DCITW) in the detection of delayed cerebral ischemia (DCI) and the change in CTP parameters from admission to DCITW following aneurysmal subarachnoid hemorrhage. METHODS Eighty patients underwent CTP at admission and during DCITW. The mean and extreme values of all CTP parameters at admission and during DCITW were compared between the DCI group and non-DCI group, and comparisons were also made between admission and DCITW within each group. The qualitative color-coded perfusion maps were recorded. Finally, the relationship between CTP parameters and DCI was assessed by receiver operating characteristic (ROC) analyses. RESULTS With the exception of cerebral blood volume (P=0.295, admission; P=0.682, DCITW), there were significant differences in the mean quantitative CTP parameters between DCI and non-DCI patients both at admission and during DCITW. In the DCI group, the extreme parameters were significantly different between admission and DCITW. The DCI group also showed a deteriorative trend in the qualitative color-coded perfusion maps. For the detection of DCI, mean transit time to the center of the impulse response function (Tmax) at admission and mean time to start (TTS) during DCITW had the largest area under curve (AUC), 0.698 and 0.789, respectively. CONCLUSION Whole-brain CTP can predict the occurrence of DCI at admission and diagnose DCI during DCITW. The extreme quantitative parameters and qualitative color-coded perfusion maps can better reflect the perfusion changes of patients with DCI from admission to DCITW.
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Affiliation(s)
- Feng You
- Department of Radiology, the First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China.,Department of Radiology, Affiliated Hangzhou First People's Hospital, Hangzhou, 310000, China
| | - Wen-Juan Tang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Chao Zhang
- Department of Radiology, the First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China
| | - Ming-Quan Ye
- School of Medical Information, Wannan Medical College, Wuhu, 241001, China
| | - Xing-Gen Fang
- Department of Neurosurgery, the First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China
| | - Yun-Feng Zhou
- Department of Radiology, the First Affiliated Hospital of Wannan Medical College, Wuhu, 241001, China.
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Megjhani M, Weiss M, Ford J, Terilli K, Kastenholz NCM, Nametz D, Kwon SB, Velazquez A, Agarwal S, Roh DJ, Conzen-Dilger C, Albanna W, Veldeman M, Connolly ES, Claassen J, Aries M, Schubert GA, Park S. Optimal Cerebral Perfusion Pressure and Brain Tissue Oxygen in Aneurysmal Subarachnoid Hemorrhage. Stroke 2023; 54:189-197. [PMID: 36314124 PMCID: PMC9780174 DOI: 10.1161/strokeaha.122.040339] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 09/30/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Targeting a cerebral perfusion pressure optimal for cerebral autoregulation (CPPopt) has been gaining more attention to prevent secondary damage after acute neurological injury. Brain tissue oxygenation (PbtO2) can identify insufficient cerebral blood flow and secondary brain injury. Defining the relationship between CPPopt and PbtO2 after aneurysmal subarachnoid hemorrhage may result in (1) mechanistic insights into whether and how CPPopt-based strategies might be beneficial and (2) establishing support for the use of PbtO2 as an adjunctive monitor for adequate or optimal local perfusion. METHODS We performed a retrospective analysis of a prospectively collected 2-center dataset of patients with aneurysmal subarachnoid hemorrhage with or without later diagnosis of delayed cerebral ischemia (DCI). CPPopt was calculated as the cerebral perfusion pressure (CPP) value corresponding to the lowest pressure reactivity index (moving correlation coefficient of mean arterial and intracranial pressure). The relationship of (hourly) deltaCPP (CPP-CPPopt) and PbtO2 was investigated using natural spline regression analysis. Data after DCI diagnosis were excluded. Brain tissue hypoxia was defined as PbtO2 <20 mmHg. RESULTS One hundred thirty-one patients were included with a median of 44.0 (interquartile range, 20.8-78.3) hourly CPPopt/PbtO2 datapoints. The regression plot revealed a nonlinear relationship between PbtO2 and deltaCPP (P<0.001) with PbtO2 decrease with deltaCPP <0 mmHg and stable PbtO2 with deltaCPP ≥0mmHg, although there was substantial individual variation. Brain tissue hypoxia (34.6% of all measurements) was more frequent with deltaCPP <0 mmHg. These dynamics were similar in patients with or without DCI. CONCLUSIONS We found a nonlinear relationship between PbtO2 and deviation of patients' CPP from CPPopt in aneurysmal subarachnoid hemorrhage patients in the pre-DCI period. CPP values below calculated CPPopt were associated with lower PbtO2. Nevertheless, the nature of PbtO2 measurements is complex, and the variability is high. Combined multimodality monitoring with CPP/CPPopt and PbtO2 should be recommended to redefine individual pressure targets (CPP/CPPopt) and retain the option to detect local perfusion deficits during DCI (PbtO2), which cannot be fulfilled by both measurements interchangeably.
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Affiliation(s)
- Murad Megjhani
- Department of Neurology, Columbia University, New York, USA
| | - Miriam Weiss
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
- Department of Neurosurgery, Kantonsspital Aarau, Aarau, Switzerland
| | - Jenna Ford
- Program in Hospital and Intensive Care Informatics, Department of Neurology, Columbia University, New York, USA
| | | | | | - Daniel Nametz
- Department of Neurology, Columbia University, New York, USA
| | - Soon Bin Kwon
- Department of Neurology, Columbia University, New York, USA
| | - Angela Velazquez
- Program in Hospital and Intensive Care Informatics, Department of Neurology, Columbia University, New York, USA
| | - Sachin Agarwal
- Program in Hospital and Intensive Care Informatics, Department of Neurology, Columbia University, New York, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York, USA
| | - David J. Roh
- Program in Hospital and Intensive Care Informatics, Department of Neurology, Columbia University, New York, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York, USA
| | | | - Walid Albanna
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - Michael Veldeman
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - E. Sander Connolly
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York, USA
- Department of Neurosurgery, Columbia University, New York, USA
| | - Jan Claassen
- Program in Hospital and Intensive Care Informatics, Department of Neurology, Columbia University, New York, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York, USA
| | - Marcel Aries
- Department of Intensive Care, Maastricht University Medical Center, Maastricht University, Maastricht, The Netherlands
- School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Gerrit A. Schubert
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
- Department of Neurosurgery, Kantonsspital Aarau, Aarau, Switzerland
| | - Soojin Park
- Department of Neurology, Columbia University, New York, USA
- Program in Hospital and Intensive Care Informatics, Department of Neurology, Columbia University, New York, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York, USA
- Department of Biomedical Informatics, Columbia University, New York, USA
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Owen B, Vangala A, Fritch C, Alsarah AA, Jones T, Davis H, Shuttleworth CW, Carlson AP. Cerebral Autoregulation Correlation With Outcomes and Spreading Depolarization in Aneurysmal Subarachnoid Hemorrhage. Stroke 2022; 53:1975-1983. [PMID: 35196873 PMCID: PMC9133018 DOI: 10.1161/strokeaha.121.037184] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Delayed cerebral ischemia remains one of the principal therapeutic targets after aneurysmal subarachnoid hemorrhage. While large vessel vasospasm may contribute to ischemia, increasing evidence suggests that physiological impairment through disrupted impaired cerebral autoregulation (CA) and spreading depolarizations (SDs) also contribute to delayed cerebral ischemia and poor neurological outcome. This study seeks to explore the intermeasure correlation of different measures of CA, as well as correlation with SD and neurological outcome. METHODS Simultaneous measurement of 7 continuous indices of CA was calculated in 19 subjects entered in a prospective study of SD in aneurysmal subarachnoid hemorrhage undergoing surgical aneurysm clipping. Intermeasure agreement was assessed, and the association of each index with modified Rankin Scale score at 90 days and occurrence of SD was assessed. RESULTS There were 4102 hours of total monitoring time across the 19 subjects. In time-resolved assessment, no CA measures demonstrated significant correlation; however, most demonstrate significant correlation averaged over 1 hour. Pressure reactivity (PRx), oxygen reactivity, and oxygen saturation reactivity were significantly correlated with modified Rankin Scale score at 90 days. PRx and oxygen reactivity also were correlated with the occurrence of SD events. Across multiple CA measure reactivity indices, a threshold between 0.3 and 0.5 was most associated with intervals containing SD. CONCLUSIONS Different continuous CA indices do not correlate well with each other on a highly time-resolved basis, so should not be viewed as interchangeable. PRx and oxygen reactivity are the most reliable indices in identifying risk of worse outcome in patients with aneurysmal subarachnoid hemorrhage undergoing surgical treatment. SD occurrence is correlated with impaired CA across multiple CA measurement techniques and may represent the pathological mechanism of delayed cerebral ischemia in patients with impaired CA. Optimization of CA in patients with aneurysmal subarachnoid hemorrhage may lead to decreased incidence of SD and improved neurological outcomes. Future studies are needed to evaluate these hypotheses and approaches.
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Affiliation(s)
- Bryce Owen
- University of New Mexico, School of Medicine
| | - Adarsh Vangala
- University of Arizona College of Medicine, Department of Internal Medicine
| | - Chanju Fritch
- Penn State School of Medicine, Department of Neurosurgery
| | - Ali A. Alsarah
- University of New Mexico School of Medicine, Department of Neurology
| | - Tom Jones
- University of New Mexico School of Medicine, Department of Psychiatry
| | - Herbert Davis
- University of New Mexico School of Medicine, Department of Internal Medicine, Division of Epidemiology, Biostatistics, and Preventive Medicine
| | | | - Andrew P. Carlson
- University of New Mexico School of Medicine, Department of Neurosurgery
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Zimmerman WD, Chang WTW. ED BP Management for Subarachnoid Hemorrhage. Curr Hypertens Rep 2022; 24:303-309. [PMID: 35608789 DOI: 10.1007/s11906-022-01199-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/15/2022] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW To review most recent literature on management of blood pressure in acute aneurysmal subarachnoid hemorrhage (SAH) and provide practice recommendations for the emergency clinician. RECENT FINDINGS There is increased risk of aneurysmal rebleeding with systolic blood pressure (SBP) greater than 160 mmHg in the acute setting. Avoiding large degrees of blood pressure variability improves clinical outcomes in aneurysmal SAH. Acute lowering of SBP to a range of 140-160 mmHg decreases risk of rebleeding while also maintaining cerebral perfusion pressure (CPP) after aneurysmal rupture. Treatment with a short acting antihypertensive agent allows for rapid titration of blood pressure (BP) and reduces BP variability. Elevations in intracranial pressure occur commonly after SAH due to increased intracranial blood volume, cerebral edema, or development of hydrocephalus. Clinicians should be familiar with changes in cerebral autoregulation and effects on CPP when treating elevated BP, in order to mitigate the risk of secondary neurological injury.
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Affiliation(s)
- W Denney Zimmerman
- Department of Neurology, University of Maryland Medical Center, Baltimore, MD, 21201, USA
| | - Wan-Tsu W Chang
- Departments of Emergency Medicine and Neurology, Program in Trauma, University of Maryland School of Medicine, 22 S. Greene St, Baltimore, MD, 21201, USA.
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Powers WJ, An H, Diringer MN. Cerebral Blood Flow and Metabolism. Stroke 2022. [DOI: 10.1016/b978-0-323-69424-7.00003-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zheng J, Sun X, Zhang X. Influence of Age-Related Complications on Clinical Outcome in Patients With Small Ruptured Cerebral Aneurysms. Front Neurol 2020; 11:131. [PMID: 32194496 PMCID: PMC7066075 DOI: 10.3389/fneur.2020.00131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 02/05/2020] [Indexed: 12/11/2022] Open
Abstract
Background: Small ruptured cerebral aneurysms (≤5 mm) account for the majority of aneurysmal subarachnoid hemorrhages, and its clinical management remains a challenge. The aim of this study was to identify the effect of age-related complications on the outcome of patients with small ruptured aneurysm. Methods: A retrospective review was performed in patients with small ruptured aneurysms who underwent microsurgical clipping or endovascular coiling from September 2012 to December 2018. According to their ages, the patients were divided into the elderly group and the non-elderly group. Baseline characteristics, clinical complications, and outcome of patients were analyzed between the two groups. A multivariate logistic regression analysis was used to determine the risk factors associated with the poor outcome of the elderly patients. Results: In the elderly group, 83 patients were treated with clipping and 50 were treated with coiling. In the non-elderly group, 188 patients were treated with clipping and 117 were treated with coiling. The incidence of neurological complications with neurologic deficit in the elderly group was significantly higher compared with that in the non-elderly group (P = 0.006). The elderly patients had a longer hospital stay (P = 0.032) and a poorer outcome (P = 0.001) compared with the non-elderly patients. A multivariate analysis showed that irregular aneurysms (P = 0.045) and ischemic events (P < 0.001) were independent risk factors associated with poor outcome in the elderly. Conclusions: Neurological complications with neurologic deficit, especially ischemic complications, were clearly more common in the elderly patients. Irregular small aneurysms or postoperative ischemic events should be paid attention as the higher risk of poor outcome in the elderly.
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Affiliation(s)
- Jianfeng Zheng
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiaochuan Sun
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiaodong Zhang
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Wolf S. Autoregulation Monitoring is Important: Even After Aneurysmal Subarachnoid Hemorrhage—Isn’t it? Neurocrit Care 2019; 31:245-246. [DOI: 10.1007/s12028-019-00778-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Silverman A, Kodali S, Strander S, Gilmore EJ, Kimmel A, Wang A, Cord B, Falcone G, Hebert R, Matouk C, Sheth KN, Petersen NH. Deviation From Personalized Blood Pressure Targets Is Associated With Worse Outcome After Subarachnoid Hemorrhage. Stroke 2019; 50:2729-2737. [PMID: 31495332 PMCID: PMC6756936 DOI: 10.1161/strokeaha.119.026282] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose- Optimal blood pressure (BP) management during the early stages of aneurysmal subarachnoid hemorrhage remains uncertain. Observational studies have found worse outcomes in patients with increased hemodynamic variability, suggesting BP optimization as a potential neuroprotective strategy. In this study, we calculated personalized BP targets at which cerebral autoregulation was best preserved. We analyzed how deviation from these limits correlates with functional outcome. Methods- We prospectively enrolled 31 patients with aneurysmal subarachnoid hemorrhage. Autoregulatory function was continuously measured by interrogating changes in near-infrared spectroscopy (NIRS)-derived tissue oxygenation-a surrogate for cerebral blood flow-as well as intracranial pressure (ICP) in response to changes in mean arterial pressure using time-correlation analysis. The resulting autoregulatory indices were used to identify the upper and lower limit of autoregulation. Percent time that mean arterial pressure exceeded limits of autoregulation was calculated for each patient. Functional outcome was assessed using the modified Rankin Scale at discharge and 90 days. Associations with outcome were analyzed using ordinal multivariate logistic regression. Results- Personalized limits of autoregulation were computed in all patients (age 57.5±13.4, 23F, mean World Federation of Neurological Surgeons 2±1, monitoring time 67.8±50.8 hours). Optimal BP and limits of autoregulation were calculated on average for 89.5±6.7% of the total monitoring period. ICP- and NIRS-derived optimal pressures strongly correlated with one another (P<0.0001). Percent time that mean arterial pressure deviated from limits of autoregulation significantly associated with worse functional outcome at discharge (NIRS, P=0.001; ICP, P=0.004) and 90 days (NIRS, P=0.002; ICP, P=0.003), adjusting separately for age, World Federation of Neurological Surgeons, vasospasm, and delayed cerebral ischemia. Conclusions- Both invasive (ICP) and noninvasive (NIRS) determination of personalized BP targets after aneurysmal subarachnoid hemorrhage is feasible, and these 2 approaches revealed significant collinearity. Furthermore, exceeding individualized limits of autoregulation was associated with poor functional outcomes.
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Affiliation(s)
| | - Sreeja Kodali
- Department of Neurology, Yale Medical School, New Haven, CT
| | | | | | | | - Anson Wang
- Department of Neurology, Yale Medical School, New Haven, CT
| | - Branden Cord
- Department of Neurosurgery, Yale Medical School, New Haven, CT
| | - Guido Falcone
- Department of Neurology, Yale Medical School, New Haven, CT
| | - Ryan Hebert
- Department of Neurosurgery, Yale Medical School, New Haven, CT
| | - Charles Matouk
- Department of Neurosurgery, Yale Medical School, New Haven, CT
| | - Kevin N. Sheth
- Department of Neurology, Yale Medical School, New Haven, CT
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