uu.seUppsala University Publications
Change search
Link to record
Permanent link

Direct link
BETA
Alternative names
Publications (10 of 82) Show all publications
Engquist, H., Lewén, A., Hillered, L., Ronne-Engström, E., Nilsson, P., Enblad, P. & Rostami, E. (2020). CBF changes and cerebral energy metabolism during hypervolemia, hemodilution, and hypertension therapy in patients with poor-grade subarachnoid hemorrhage. Journal of Neurosurgery
Open this publication in new window or tab >>CBF changes and cerebral energy metabolism during hypervolemia, hemodilution, and hypertension therapy in patients with poor-grade subarachnoid hemorrhage
Show others...
2020 (English)In: Journal of Neurosurgery, ISSN 0022-3085Article in journal (Refereed) Published
Keywords
subarachnoid hemorrhage, cerebral blood flow, delayed cerebral ischemia, xenon CT, XeCT
National Category
Clinical Medicine
Research subject
Neurosurgery
Identifiers
urn:nbn:se:uu:diva-400694 (URN)10.3171/2019.11.JNS192759 (DOI)
Note

The Journal of Neurosurgery, publ online Jan 10, 2020 (accepted for publ Nov 5, 2019)

Available from: 2020-01-02 Created: 2020-01-02 Last updated: 2020-02-05Bibliographically approved
Fahlström, M., Lewén, A., Enblad, P., Larsson, E.-M. & Wikström, J. (2020). High Intravascular Signal Arterial Transit Time Artifacts Have Negligible Effects on Cerebral Blood Flow and Cerebrovascular Reserve Capacity Measurement Using Single Postlabel Delay Arterial Spin-Labeling in Patients with Moyamoya Disease. American Journal of Neuroradiology, 41(3), 430-436
Open this publication in new window or tab >>High Intravascular Signal Arterial Transit Time Artifacts Have Negligible Effects on Cerebral Blood Flow and Cerebrovascular Reserve Capacity Measurement Using Single Postlabel Delay Arterial Spin-Labeling in Patients with Moyamoya Disease
Show others...
2020 (English)In: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 41, no 3, p. 430-436Article in journal (Refereed) Published
Abstract [en]

BACKGROUND AND PURPOSE: Arterial spin-labeling-derived CBF values may be affected by arterial transit time artefacts. Thus, our aim was to assess to what extent arterial spin-labeling–derived CBF and cerebrovascular reserve capacity values in major vascular regions are overestimated due to the arterial transit time artifacts in patients with Moyamoya disease.

MATERIALS AND METHODS: Eight patients with Moyamoya disease were included before or after revascularization surgery. CBF maps were acquired using a 3D pseudocontinuous arterial spin-labeling sequence, before and 5, 15, and 25 minutes after an IV acetazolamide injection and were registered to each patient’s 3D-T1-weighted images. Vascular regions were defined by spatial normalization to a Montreal Neurological Institute–based vascular regional template. The arterial transit time artifacts were defined as voxels with high signal intensity corresponding to the right tail of the histogram for a given vascular region, with the cutoff selected by visual inspection. Arterial transit time artifact maps were created and applied as masks to exclude arterial transit time artifacts on CBF maps, to create corrected CBF maps. The cerebrovascular reserve capacity was calculated as CBF after acetazolamide injection relative to CBF at baseline for corrected and uncorrected CBF values, respectively.

RESULTS: A total of 16 examinations were analyzed. Arterial transit time artifacts were present mostly in the MCA, whereas the posterior cerebral artery was generally unaffected. The largest differences between corrected and uncorrected CBF and cerebrovascular reserve capacity values, reported as patient group average ratio and percentage point difference, respectively, were 0.978 (95% CI, 0.968–0.988) and 1.8 percentage points (95% CI, 0.3–3.2 percentage points). Both were found in the left MCA, 15 and 5 minutes post-acetazolamide injection, respectively.

CONCLUSIONS: Arterial transit time artifacts have negligible overestimation effects on calculated vascular region-based CBF and cerebrovascular reserve capacity values derived from single-delay 3D pseudocontinuous arterial spin-labeling.

National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-405377 (URN)10.3174/ajnr.A6411 (DOI)000521965200016 ()32115416 (PubMedID)
Available from: 2020-02-27 Created: 2020-02-27 Last updated: 2020-04-27Bibliographically approved
Lenell, S., Nyholm, L., Lewén, A. & Enblad, P. (2019). Clinical outcome and prognostic factors in elderly traumatic brain injury patients receiving neurointensive care. Acta Neurochirurgica, 161(6), 1243-1254
Open this publication in new window or tab >>Clinical outcome and prognostic factors in elderly traumatic brain injury patients receiving neurointensive care
2019 (English)In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 161, no 6, p. 1243-1254Article in journal (Refereed) Published
Abstract [en]

Background: The probability of favorable outcome after traumatic brain injury (TBI) decreases with age. Elderly,≥60 years, are an increasing part of our population. Recent studies have shown an increase of favorable outcome in elderly over time. However,the optimal patient selection and neurointensive care (NIC) treatments may differ in the elderly and the young. The aims of this study were to examine outcome in a larger group of elderly TBI patients receiving NIC and to identify demographic and treatmentrelated prognostic factors.

Methods: Patients with TBI≥60 years receiving NIC at our department between 2008 and 2014 were included. Demographics, co-morbidity, admission characteristics, and type of treatments were collected. Clinical outcome at around 6 months was assessed. Potential prognostic factors were included in univariate and multivariate regression analysis with favorable outcomeas dependent variable.

Results: Two hundred twenty patients with mean age 70 years (median 69; range 60–87) were studied. Overall, favorable outcome was 46% (Extended Glasgow Outcome Scale (GOSE) 5–8), unfavorable outcome 27% (GOSE 2–4), and mortality 27% (GOSE 1). Significant independent negative prognostic variables were high age (p< 0.05), multiple injuries (p<0.05),GCSM≤3 on admission (p< 0.05), and mechanical ventilation (p<0.001).

Conclusions: Overall, the elderly TBI patients> 60 years receiving modern NIC in this study had a fair chance of favorable outcome without large risks for severe deficits and vegetative state, also in patients over 75 years of age. High age, multiple injuries, GCS M≤3 on admission, and mechanical ventilation proved to be independent negative prognostic factors. The results underline that a selected group of elderly with TBI should have access to NIC

Place, publisher, year, edition, pages
SPRINGER WIEN, 2019
Keywords
Traumatic brain injury, Elderly, Outcome, Quality register, Neurointensive care, Prognostic factors
National Category
Neurology
Identifiers
urn:nbn:se:uu:diva-385969 (URN)10.1007/s00701-019-03893-6 (DOI)000468224800028 ()30980243 (PubMedID)
Available from: 2019-06-18 Created: 2019-06-18 Last updated: 2019-06-18Bibliographically approved
Donald, R., Howells, T., Piper, I., Enblad, P., Nilsson, P., Chambers, I., . . . Stell, A. (2019). Forewarning of hypotensive events using a Bayesian artificial neural network in neurocritical care. Journal of clinical monitoring and computing, 33(1), 39-51
Open this publication in new window or tab >>Forewarning of hypotensive events using a Bayesian artificial neural network in neurocritical care
Show others...
2019 (English)In: Journal of clinical monitoring and computing, ISSN 1387-1307, E-ISSN 1573-2614, Vol. 33, no 1, p. 39-51Article in journal (Refereed) Published
Abstract [en]

Traumatically brain injured (TBI) patients are at risk from secondary insults. Arterial hypotension, critically low blood pressure, is one of the most dangerous secondary insults and is related to poor outcome in patients. The overall aim of this study was to get proof of the concept that advanced statistical techniques (machine learning) are methods that are able to provide early warning of impending hypotensive events before they occur during neuro-critical care. A Bayesian artificial neural network (BANN) model predicting episodes of hypotension was developed using data from 104 patients selected from the BrainIT multi-center database. Arterial hypotension events were recorded and defined using the Edinburgh University Secondary Insult Grades (EUSIG) physiological adverse event scoring system. The BANN was trained on a random selection of 50% of the available patients (n = 52) and validated on the remaining cohort. A multi-center prospective pilot study (Phase 1, n = 30) was then conducted with the system running live in the clinical environment, followed by a second validation pilot study (Phase 2, n = 49). From these prospectively collected data, a final evaluation study was done on 69 of these patients with 10 patients excluded from the Phase 2 study because of insufficient or invalid data. Each data collection phase was a prospective non-interventional observational study conducted in a live clinical setting to test the data collection systems and the model performance. No prediction information was available to the clinical teams during a patient's stay in the ICU. The final cohort (n = 69), using a decision threshold of 0.4, and including false positive checks, gave a sensitivity of 39.3% (95% CI 32.9-46.1) and a specificity of 91.5% (95% CI 89.0-93.7). Using a decision threshold of 0.3, and false positive correction, gave a sensitivity of 46.6% (95% CI 40.1-53.2) and specificity of 85.6% (95% CI 82.3-88.8). With a decision threshold of 0.3, > 15min warning of patient instability can be achieved. We have shown, using advanced machine learning techniques running in a live neuro-critical care environment, that it would be possible to give neurointensive teams early warning of potential hypotensive events before they emerge, allowing closer monitoring and earlier clinical assessment in an attempt to prevent the onset of hypotension. The multi-centre clinical infrastructure developed to support the clinical studies provides a solid base for further collaborative research on data quality, false positive correction and the display of early warning data in a clinical setting.

Keywords
Traumatic brain injury, Neuro-intensive care, Bayesian prediction, Clinical study results
National Category
Anesthesiology and Intensive Care
Identifiers
urn:nbn:se:uu:diva-374422 (URN)10.1007/s10877-018-0139-y (DOI)000454820400007 ()29799079 (PubMedID)
Funder
EU, Horizon 2020, IST-2007-217049
Available from: 2019-01-29 Created: 2019-01-29 Last updated: 2019-01-29Bibliographically approved
Svedung-Wettervik, T., Howells, T., Ronne-Engström, E., Hillered, L., Lewén, A., Enblad, P. & Rostami, E. (2019). High Arterial Glucose is Associated with Poor Pressure Autoregulation, High Cerebral Lactate/Pyruvate Ratio and Poor Outcome Following Traumatic Brain Injury. Neurocritical Care, 31(3), 526-533
Open this publication in new window or tab >>High Arterial Glucose is Associated with Poor Pressure Autoregulation, High Cerebral Lactate/Pyruvate Ratio and Poor Outcome Following Traumatic Brain Injury
Show others...
2019 (English)In: Neurocritical Care, ISSN 1541-6933, E-ISSN 1556-0961, Vol. 31, no 3, p. 526-533Article in journal (Refereed) Published
Abstract [en]

Background Arterial hyperglycemia is associated with poor outcome in traumatic brain injury (TBI), but the pathophysiology is not completely understood. Previous preclinical and clinical studies have indicated that arterial glucose worsens pressure autoregulation. The aim of this study was to evaluate the relationship of arterial glucose to both pressure reactivity and cerebral energy metabolism. Method This retrospective study was based on 120 patients with severe TBI treated at the Uppsala University hospital, Sweden, 2008-2018. Data from cerebral microdialysis (glucose, pyruvate, and lactate), arterial glucose, and pressure reactivity index (PRx55-15) were analyzed the first 3 days post-injury. Results High arterial glucose was associated with poor outcome/Glasgow Outcome Scale-Extended at 6-month follow-up (r = - 0.201, p value = 0.004) and showed a positive correlation with both PRx55-15 (r = 0.308, p = 0.001) and cerebral lactate/pyruvate ratio (LPR) days 1-3 (r = 0. 244, p = 0.014). Cerebral lactate-to-pyruvate ratio and PRx55-15 had a positive association day 2 (r = 0.219, p = 0.048). Multivariate linear regression analysis showed that high arterial glucose predicted poor pressure autoregulation on days 1 and 2. Conclusions High arterial glucose was associated with poor outcome, poor pressure autoregulation, and cerebral energy metabolic disturbances. The latter two suggest a pathophysiological mechanism for the negative effect of arterial hyperglycemia, although further studies are needed to elucidate if the correlations are causal or confounded by other factors.

Place, publisher, year, edition, pages
HUMANA PRESS INC, 2019
Keywords
Traumatic brain injury, Glucose, Autoregulation, Cerebral energy metabolism
National Category
Anesthesiology and Intensive Care
Identifiers
urn:nbn:se:uu:diva-400725 (URN)10.1007/s12028-019-00743-2 (DOI)000501700900011 ()31123993 (PubMedID)
Available from: 2020-03-05 Created: 2020-03-05 Last updated: 2020-03-05Bibliographically approved
Vlachogiannis, P., Hillered, L., Khalil, F., Enblad, P. & Ronne-Engström, E. (2019). Interleukin-6 Levels in Cerebrospinal Fluid and Plasma in Patients with Severe Spontaneous Subarachnoid Hemorrhage. World Neurosurgery, 122, E612-E618
Open this publication in new window or tab >>Interleukin-6 Levels in Cerebrospinal Fluid and Plasma in Patients with Severe Spontaneous Subarachnoid Hemorrhage
Show others...
2019 (English)In: World Neurosurgery, ISSN 1878-8750, E-ISSN 1878-8769, Vol. 122, p. E612-E618Article in journal (Refereed) Published
Abstract [en]

BACKGROUND: Inflammatory processes play a key role in the pathophysiology of subarachnoid hemorrhage (SAH). This study evaluated whether different temporal patterns of intrathecal and systemic inflammation could be identified in the acute phase after SAH. The intensity of the inflammation was also assessed in clinical subgroups. METHODS: Cerebrospinal fluid (CSF) and blood samples were collected at days 1, 4, and 10 after ictus in 44 patients with severe SAH. Interleukin-6 (IL-6) was analyzed by a routine monoclonal antibody-based method. Median IL-6 values for each day were calculated. Day 4 IL-6 values were compared in dichotomized groups (age, sex, World Federation of Neurosurgical Societies [WFNS] grade, Fisher scale grade, outcome, vasospasm, central nervous system infection and systemic infections). RESULTS: CSF IL-6 levels were significantly elevated from day 1 to days 4 and 10, whereas plasma IL-6 showed a different trend at lower levels. Median CSF IL-6 concentrations for days 1, 4, and 10 were 876.5, 3361, and 1567 ng/L, whereas plasma was 26, 27.5, and 15.9 ng/L, respectively. No significant differences in CSF concentrations were observed between the subgroups, with the most prominent one being in day 4 IL-6 in the WFNS subgroups (grades 1-3 vs. 4-5, 1158.5 vs. 5538 ng/L; P = 0.056). Patients with systemic infection had significantly higher plasma IL-6 concentrations than patients without infection (31 vs. 16.05 ng/L, respectively; P = 0.028). CONCLUSIONS: Distinctly different inflammatory patterns could be seen intrathecally compared with the systemic circulation. In plasma, a significant difference in the intensity of the inflammation was seen in cases with systemic infection. No other subgroup showed statistically significant differences.

Place, publisher, year, edition, pages
ELSEVIER SCIENCE INC, 2019
Keywords
Inflammatory response, Interleukin-6, Neuroinflammation, SAH, Subarachnoid hemorrhage
National Category
Neurology
Identifiers
urn:nbn:se:uu:diva-377213 (URN)10.1016/j.wneu.2018.10.113 (DOI)000457328100075 ()
Available from: 2019-02-25 Created: 2019-02-25 Last updated: 2019-02-25Bibliographically approved
Abu Hamdeh, S., Marklund, N., Lewén, A., Howells, T., Raininko, R., Wikström, J. & Enblad, P. (2019). Intracranial pressure elevations in diffuse axonal injury: association with nonhemorrhagic MR lesions in central mesencephalic structures. Journal of Neurosurgery, 131(2), 604-611
Open this publication in new window or tab >>Intracranial pressure elevations in diffuse axonal injury: association with nonhemorrhagic MR lesions in central mesencephalic structures
Show others...
2019 (English)In: Journal of Neurosurgery, ISSN 0022-3085, E-ISSN 1933-0693, Vol. 131, no 2, p. 604-611Article in journal (Refereed) Published
Abstract [en]

Objective: Increased intracranial pressure (ICP) in patients with severe traumatic brain injury (TBI) with diffuse axonal injury (DAI) is not well defined. This study investigated the occurrence of increased ICP and whether clinical factors and lesion localization on MRI were associated with increased ICP in patients with DAI.

Methods: Fifty-two patients with severe TBI (median age 24 years, range 9–61 years), who had undergone ICP monitoring and had DAI on MRI, as determined using T2*-weighted gradient echo, susceptibility-weighted imaging, and diffusion-weighted imaging (DWI) sequences, were enrolled. The proportion of good monitoring time (GMT) with ICP > 20 mm Hg during the first 120 hours postinjury was calculated and associations with clinical and MRI-related factors were evaluated using linear regression.

Results: All patients had episodes of ICP > 20 mm Hg. The mean proportion of GMT with ICP > 20 mm Hg was 5%, and 27% of the patients (14/52) spent more than 5% of GMT with ICP > 20 mm Hg. The Glasgow Coma Scale motor score at admission (p = 0.04) and lesions on DWI sequences in the substantia nigra and mesencephalic tegmentum (SN-T, p = 0.001) were associated with the proportion of GMT with ICP > 20 mm Hg. In multivariable linear regression, lesions on DWI sequences in SN-T (8% of GMT with ICP > 20 mm Hg, 95% CI 3%–13%, p = 0.004) and young age (−0.2% of GMT with ICP > 20 mm Hg, 95% CI −0.07% to −0.3%, p = 0.002) were associated with increased ICP.

Conclusions: Increased ICP occurs in approximately one-third of patients with severe TBI who have DAI. Age and lesions on DWI sequences in the central mesencephalon (i.e., SN-T) are associated with elevated ICP. These findings suggest that MR lesion localization may aid prediction of increased ICP in patients with DAI.

Abbreviations: ADC = apparent diffusion coefficient; CPP = cerebral perfusion pressure; DAI = diffuse axonal injury; DWI = diffusion-weighted imaging; EVD = external ventricular drain; GCS = Glasgow Coma Scale; GMT = good monitoring time; GOSE = Glasgow Outcome Scale–Extended; ICC = intraclass correlation coefficient; ICP = intracranial pressure; MAP = mean arterial blood pressure; NICU = neurointensive care unit; SN-T = substantia nigra and mesencephalic tegmentum; SWI = susceptibility-weighted imaging; TBI = traumatic brain injury; T2*GRE = T2*-weighted gradient echo.

Keywords
diffuse axonal injury, MRI, elevated ICP, intracranial pressure, TBI, traumatic brain injury, diffusion-weighted imaging, trauma
National Category
Neurology Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-362207 (URN)10.3171/2018.4.JNS18185 (DOI)000478642100036 ()30215559 (PubMedID)
Note

Correction in: JOURNAL OF NEUROSURGERY, Volume: 131, Issue: 2, Pages: 637-638, DOI: 10.3171/2018.10.JNS18185a

Available from: 2018-10-02 Created: 2018-10-02 Last updated: 2019-10-18Bibliographically approved
Svedung-Wettervik, T., Howells, T., Hillered, L., Nilsson, P., Engquist, H., Lewén, A., . . . Rostami, E. (2019). Mild hyperventilation in traumatic brain injury - relation to cerebral energy metabolism, pressure autoregulation and clinical outcome. World Neurosurgery, 133, e567-e575
Open this publication in new window or tab >>Mild hyperventilation in traumatic brain injury - relation to cerebral energy metabolism, pressure autoregulation and clinical outcome
Show others...
2019 (English)In: World Neurosurgery, ISSN 1878-8750, E-ISSN 1878-8769, Vol. 133, p. e567-e575Article in journal (Refereed) Published
Abstract [en]

OBJECTIVE: Hyperventilation is a controversial treatment in traumatic brain injury (TBI). Prophylactic severe hyperventilation below 3.3 kPa/25 mm Hg) is generally avoided, due to the risk of cerebral ischemia. Mild hyperventilation (arterial pCO2 within 4.0-4.5 kPa/30-34 mm Hg) in cases of intracranial hypertension is commonly used, but its safety and benefits are not fully elucidated. The aim of this study was to evaluate the use of mild hyperventilation and its relation to, cerebral energy metabolism, pressure autoregulation and clinical outcome in TBI.

METHOD: This retrospective study was based on 120 patients with severe TBI treated at the neurointensive care unit, Uppsala university hospital, Sweden, 2008-2018. Data from cerebral microdialysis (glucose, pyruvate and lactate), arterial pCO2 and pressure reactivity index (PRx55-15) were analyzed for the first three days post-injury.

RESULTS: Mild hyperventilation 4.0-4.5 kPa (30-34 mm Hg) was more frequently used early and the patients were gradually normoventilated. Low pCO2 was associated with slightly higher intracranial pressure and slightly lower cerebral perfusion pressure (p-value < 0.01). There was no univariate correlation between low pCO2 and worse cerebral energy metabolism. Multiple linear regression analysis showed that mild hyperventilation was associated with lower PRx55-15 day 2 (p-value = 0.03), suggesting better pressure autoregulation. Younger age and lower ICP were also associated with lower PRx55-15.

CONCLUSIONS: These findings support the notion that mild hyperventilation is safe and may improve cerebrovascular reactivity.

Keywords
Traumatic brain injury, cerebral energy metabolism, clinical outcome, hyperventilation, neurointensive-care, pressure reactivity
National Category
Surgery
Research subject
Neurosurgery
Identifiers
urn:nbn:se:uu:diva-395237 (URN)10.1016/j.wneu.2019.09.099 (DOI)000503993700118 ()31561041 (PubMedID)
Available from: 2019-10-15 Created: 2019-10-15 Last updated: 2020-01-22Bibliographically approved
Dyhrfort, P., Shen, Q., Clausen, F., Eriksson, M., Enblad, P., Kamali-Moghaddam, M., . . . Hillered, L. (2019). Monitoring of Protein Biomarkers of Inflammation in Human Traumatic Brain Injury Using Microdialysis and Proximity Extension Assay Technology in Neurointensive Care. Journal of Neurotrauma, 36(20), 2872-2885
Open this publication in new window or tab >>Monitoring of Protein Biomarkers of Inflammation in Human Traumatic Brain Injury Using Microdialysis and Proximity Extension Assay Technology in Neurointensive Care
Show others...
2019 (English)In: Journal of Neurotrauma, ISSN 0897-7151, E-ISSN 1557-9042, Vol. 36, no 20, p. 2872-2885Article in journal (Refereed) Published
Abstract [en]

Traumatic brain injury (TBI) is followed by secondary injury mechanisms strongly involving neuroinflammation. To monitor the complex inflammatory cascade in human TBI, we used cerebral microdialysis (MD) and multiplex proximity extension assay (PEA) technology and simultaneously measured levels of 92 protein biomarkers of inflammation in MD samples every three hours for five days in 10 patients with severe TBI under neurointensive care. One mu L MD samples were incubated with paired oligonucleotide-conjugated antibodies binding to each protein, allowing quantification by real-time quantitative polymerase chain reaction. Sixty-nine proteins were suitable for statistical analysis. We found five different patterns with either early (<48 h; e.g., CCL20, IL6, LIF, CCL3), mid (48-96 h; e.g., CCL19, CXCL5, CXCL10, MMP1), late (>96 h; e.g., CD40, MCP2, MCP3), biphasic peaks (e.g., CXCL1, CXCL5, IL8) or stable (e.g., CCL4, DNER, VEGFA)/low trends. High protein levels were observed for e.g., CXCL1, CXCL10, MCP1, MCP2, IL8, while e.g., CCL28 and MCP4 were detected at low levels. Several proteins (CCL8, -19, -20, -23, CXCL1, -5, -6, -9, -11, CST5, DNER, Flt3L, and SIRT2) have not been studied previously in human TBI. Cross-correlation analysis revealed that LIF and CXCL5 may play a central role in the inflammatory cascade. This study provides a unique data set with individual temporal trends for potential inflammatory biomarkers in patients with TBI. We conclude that the combination of MD and PEA is a powerful tool to map the complex inflammatory cascade in the injured human brain. The technique offers new possibilities of protein profiling of complex secondary injury pathways.

Place, publisher, year, edition, pages
MARY ANN LIEBERT, INC, 2019
Keywords
biomarkers, inflammation, microdialysis, molecular tools, neurointensive care, proteomics, traumatic brain injury
National Category
Neurology
Identifiers
urn:nbn:se:uu:diva-396069 (URN)10.1089/neu.2018.6320 (DOI)000472621900001 ()31017044 (PubMedID)
Funder
Swedish Research CouncilVinnova
Available from: 2019-10-30 Created: 2019-10-30 Last updated: 2020-04-08Bibliographically approved
Engquist, H., Rostami, E. & Enblad, P. (2019). Temporal Dynamics of Cerebral Blood Flow During the Acute Course of Severe Subarachnoid Hemorrhage Studied by Bedside Xenon-Enhanced CT. Neurocritical Care, 30(2), 280-290
Open this publication in new window or tab >>Temporal Dynamics of Cerebral Blood Flow During the Acute Course of Severe Subarachnoid Hemorrhage Studied by Bedside Xenon-Enhanced CT
2019 (English)In: Neurocritical Care, ISSN 1541-6933, E-ISSN 1556-0961, Vol. 30, no 2, p. 280-290Article in journal (Refereed) Published
Abstract [en]

Background: Compromised cerebral blood flow (CBF) is a crucial factor in delayed cerebral ischemia after subarachnoid hemorrhage (SAH). Repeated measurement of CBF may improve our understanding of the temporal dynamics following SAH. The aim of this study was to assess CBF at different phases of the acute course in poor-grade SAH patients, hypothesizing more pronounced disturbances at day 4-7, and that the initial level of CBF determines the following course of CBF.

Methods: Mechanically ventilated SAH patients were scheduled for bedside measurement of regional and global cortical CBF at day 0-3, 4-7, and 8-12, using xenon-enhanced computed tomography in a mobile setup. Patients were dichotomized depending on high or low initial global cortical CBF and cutoff level 30ml/100g/min.

Results: Eighty-one patients were included, and 51 had measurements at day 0-3 and 4-7. In patients with high initial CBF, the level was unchanged at day 4-7; 37.7 (IQR 32.6-46.7) ml/100g/min versus 36.8 (IQR 29.5-44.8). The low-CBF group showed a slight increase from 23.6 (IQR 21.0-28.1) ml/100g/min to 28.4 (IQR 22.7-38.3) (P=0.025), still markedly lower than the high-CBF group (P=0.016). In the low-CBF group, CBF increased in patients who received hypertension, hypervolemia, and hemodilution (HHH therapy) but remained low in standard treated patients. For the subset of 27 patients examined also at day 8-12, the differences depending on initial CBF level were no longer statistically significant. Among patients with still low CBF at day 4-7, the proportion who had poor short-term outcome was 55% compared to 35% (n.s.) for patients with high CBF.

Conclusions: CBF studied in poor-grade SAH patients at large did not show any statistically significant changes over time. Stratifying patients by high or low initial CBF and whether HHH therapy was given revealed an association between low initial CBF and persistent low CBF at day 4-7. These findings may be of clinical relevance in managing SAH patients with low early CBF.

Place, publisher, year, edition, pages
HUMANA PRESS INC, 2019
Keywords
Subarachnoid hemorrhage, Delayed cerebral ischemia, Cerebral blood flow, Xenon-CT, XeCT, Temporal, Sequential
National Category
Anesthesiology and Intensive Care
Identifiers
urn:nbn:se:uu:diva-380427 (URN)10.1007/s12028-019-00675-x (DOI)000461380900008 ()30790226 (PubMedID)
Available from: 2019-04-01 Created: 2019-04-01 Last updated: 2020-01-10Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-4364-1919

Search in DiVA

Show all publications