Background and purpose: Involvement of deep venous structures is associated with worse outcomes i... more Background and purpose: Involvement of deep venous structures is associated with worse outcomes in patients with cerebral venous sinus thrombosis (CVST); however, the impact of clot burden has not been studied. The aim of this study was to assess the value of a novel quantitative clot burden score as an independent predictor of clinical outcomes. Methods: We retrospectively reviewed all patients admitted to University of Iowa Health Care with CVST between 2004-2014. All patients received standard of care medical management per AHA/ASA recommendations. The degree of the thrombosis was categorized in admission MR venograms as (partial=1 vs. complete occlusion=2). Clot burden scores were computed as the sum of the thrombosis degree in the following vessels: cerebral veins (cortical veins, internal cerebral, vein of Rosenthal, vein of Galen) and cerebral sinuses (superior sagittal, inferior sagittal, straight, torcula, transverse/sigmoid). The primary outcome was modified Rankin Scale (mRS) at discharge. Secondary outcomes included hemorrhage, infarction, and cerebral edema. Multiple regressions were conducted to examine effects of clot burden scores on each of the four outcomes. Results: 115 patients met inclusion criteria, 76 women, and mean age 42. Thrombosis in cerebral veins area was noted in 58(50%), clot burden score Median=4, IQR=2; while 108(96%) had thrombosis in the cerebral sinuses area, Median=4, IQR=5. Clot burden in cerebral veins (p=.005) but not in cerebral sinuses, was associated with worse discharge mRS, r= .22. This effect remained significant when adjusting for age and gender (p=.002), but not when adjusting for complications including ICH, infarct, edema. Importantly, higher clot burden score in the cerebral veins predicted ICH (OR=1.73, p
Background: Anticoagulation is considered the first-line treatment for cerebral venous thrombosis... more Background: Anticoagulation is considered the first-line treatment for cerebral venous thrombosis (CVT). However, a subset of patients does not respond. Data from case studies suggest endovascular treatment (ET) may be beneficial in such cases. The Nationwide Inpatient Sample (NIS), representing a 20% stratified sample of 7 million annual hospital admissions was used to evaluate the safety and efficacy of ET compared to conservative management in CVT. Methods: We extracted cases from NIS database for years 2004-2013 using ICD 9-CM codes: 437.6, 325, and 671.5. Data related to mechanical thrombectomy (MT) and/or thrombolysis was searched using ICD 9 CPT codes 39.74 and 99.10. Weights were applied to each admission per NIS recommendations to obtain national representation. Groups were matched with respect to age, gender and Charlson index. Data was further adjusted for injury severity score (presence of ICH, stroke, paralysis, midline shift, coma, status epilepticus or need for intubation). Results: Out of 42,889 weighted estimates of CVT cases, 1058 (2%) received ET (616 cases of thrombolysis alone and 442 cases of MT +/- thrombolysis). Patients who received ET were slightly older with higher comorbidity score, and CVT associated complications including ischemic stroke, ICH, coma, status epilepticus, cerebral edema with midline shift and need for endotracheal intubation. Patients who received ET had higher likelihood of having hematological disorders and severe dehydration and lesser likelihood of infection and trauma as underlying etiology of the condition. ET (thrombolysis alone and mechanical thrombectomy +/- thrombolysis) appeared to be significantly associated mortality and bad discharge outcomes in stepwise logistic regression analyses as well as matched paired analyses (Table 1). Conclusion: ET appears to be associated with increased mortality and poor discharge outcomes when compared to conservative treatment in the real-world setting.
... 0 (no smiling) to 3 (large smile, with lips stretched, mouth open, the bulging of cheeks, and... more ... 0 (no smiling) to 3 (large smile, with lips stretched, mouth open, the bulging of cheeks, and the crin-kling of eyes). ... We thank Kate Nichols, Jennifer Voaklander, Lindsey Lange, Amanda Friesenborg, Michelle Martel, Amy Knaack, Alissa Chisholm, and many other students and ...
PDFTech ReportSPR 90-00-SLDR-010Traffic accidentsHuman factors in accidentsSleep deprivationAccid... more PDFTech ReportSPR 90-00-SLDR-010Traffic accidentsHuman factors in accidentsSleep deprivationAccident prone driversField testsAttentionMemoryFatigue (Physiological condition)United StatesIowa. Dept. of TransportationRizzo, MatthewTippin, JonAksan, NazanUniversity of Iowa Hospitals & Clinics. Dept. of NeurologyUnited States. Federal Highway AdministrationNTL-SAFETY AND SECURITY-AccidentsNTL-SAFETY AND SECURITY-Human FactorsUS Transportation CollectionExcessive daytime sleepiness underpins a large number of the reported motor vehicle crashes. Fair and accurate fieldmeasures are needed to identify at-risk drivers who have been identified as potentially driving in a sleep deprived state onthe basis of erratic driving behavior. The purpose of this research study was to evaluate a set of cognitive tests that canassist Motor Vehicle Enforcement Officers on duty in identifying drivers who may be engaged in sleep impaired driving.Currently no gold standard test exists to judge sleepiness in the field. Previous research has shown that PsychomotorVigilance Task (PVT) is sensitive to sleep deprivation. The first goal of the current study was to evaluate whethercomputerized tests of attention and memory, more brief than PVT, would be as sensitive to sleepiness effects. The secondgoal of the study was to evaluate whether objective and subjective indices of acute and cumulative sleepiness predictedcognitive performance. Findings showed that sleepiness effects were detected in three out of six tasks. Furthermore, PVTwas the only task that showed a consistent slowing of both \ue2\u20ac\u2dcbest\ue2\u20ac\u2122, i.e. minimum, and \ue2\u20ac\u2dctypical\ue2\u20ac\u2122 responses, median RT due tosleepiness. However, PVT failed to show significant associations with objective measures of sleep deprivation (number ofhours awake). The findings indicate that sleepiness tests in the field have significant limitations. The findings clearlyshow that it will not be possible to set absolute performance thresholds to identify sleep-impaired drivers based oncognitive performance on any test. Cooperation with industry to adjust work and rest cycles, and incentives to complywith those regulations will be critical components of a broad policy to prevent sleepy truck drivers from getting on theroad
Proceedings of the 7th International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design : driving assessment 2013, Oct 10, 2017
Background and Purpose: Obstruction of venous drainage may lead to venous hypertension, edema, in... more Background and Purpose: Obstruction of venous drainage may lead to venous hypertension, edema, infarction or intracerebral hemorrhage (ICH) in patients with cerebral venous thrombosis (CVST). While the presence of ICH and infarction are associated with worse outcomes, the independent effect of edema remains unknown. We aimed to evaluate the impact of the characteristics of brain edema on functional outcomes as measured by the modified Rankin Scale (mRS) at discharge. Methods: We retrospectively reviewed all patients who presented to the University of Iowa Health Care with CVST between 2004-2014. All patients received standard of care management per available AHA/ASA recommendations. Edema was categorized as focal vasogenic, focal cytotoxic or global cerebral edema (GCE). Vasogenic edema was described as hyperintensity on FLAIR MRI sequences around the location of venous clot while cytotoxic edema was noted when hyperintensities were visualized around the location of ICH/ venous infa...
Background and purpose: Unfractionated Heparin (UFH) infusion represents the most commonly used t... more Background and purpose: Unfractionated Heparin (UFH) infusion represents the most commonly used therapy in the acute management of cerebral venous sinus thrombosis (CVST). effectiveness of heparin in reaching therapeutic anti-coagulation levels has not been well studied in this population. Identifying subgroup of patients who will not respond to Heparin may prove useful in studying alternative treatments such as the new oral anticoagulants and endovascular therapy. We aimed to evaluate the initial response to heparin infusion measured by partial thromboplastin time (PTT) and it implication in discharge outcome. Methods: Retrospective review of all consecutive patients at University of Iowa Hospitals and Clinics between 2004-2014 with CVST was conducted. All patients were treated with initial weight based bolus (14units/kg) of UFH followed by infusion. Consecutive PTT values in the first 48hrs of admission were classified as either therapeutic (40-87), supra-therapeutic (>87), or ...
doi: 10.3389/fpsyg.2014.01288 Habituation of parasympathetic-mediated heart rate responses to rec... more doi: 10.3389/fpsyg.2014.01288 Habituation of parasympathetic-mediated heart rate responses to recurring acoustic startle
In this study, EEG (EEG-MPF, EEG-α/β), heart rate variability (RRV3), tracking error and subjecti... more In this study, EEG (EEG-MPF, EEG-α/β), heart rate variability (RRV3), tracking error and subjective rating of fatigue (drowsiness) while performing a simulated driving task were measured. The relation between these measurements and drowsiness was analyzed. As a result, EEG-MPF tended to decrease with the increase of drowsiness. It tended that EEG-α/β, RRV3 and tracking error increased with the increase of drowsiness. Then, a method for predicting drowsiness by applying Bayesian estimation to physiological measurements was proposed. Bayesian estimation carries out a statistical inference using some kind of evidences or observations and calculating the probability that a hypothesis is true. An attempt was made to predicting drowsiness by applying Bayesian estimation to psychological parameters such as EEG-MPF, EEG-α/β, RRV3. As a result, it was suggested that the proposed method can predict the symptom of decreased consciousness (drowsiness).
Proceedings of the 8th International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design: driving assessment 2015, 2015
Background and purpose: Involvement of deep venous structures is associated with worse outcomes i... more Background and purpose: Involvement of deep venous structures is associated with worse outcomes in patients with cerebral venous sinus thrombosis (CVST); however, the impact of clot burden has not been studied. The aim of this study was to assess the value of a novel quantitative clot burden score as an independent predictor of clinical outcomes. Methods: We retrospectively reviewed all patients admitted to University of Iowa Health Care with CVST between 2004-2014. All patients received standard of care medical management per AHA/ASA recommendations. The degree of the thrombosis was categorized in admission MR venograms as (partial=1 vs. complete occlusion=2). Clot burden scores were computed as the sum of the thrombosis degree in the following vessels: cerebral veins (cortical veins, internal cerebral, vein of Rosenthal, vein of Galen) and cerebral sinuses (superior sagittal, inferior sagittal, straight, torcula, transverse/sigmoid). The primary outcome was modified Rankin Scale (mRS) at discharge. Secondary outcomes included hemorrhage, infarction, and cerebral edema. Multiple regressions were conducted to examine effects of clot burden scores on each of the four outcomes. Results: 115 patients met inclusion criteria, 76 women, and mean age 42. Thrombosis in cerebral veins area was noted in 58(50%), clot burden score Median=4, IQR=2; while 108(96%) had thrombosis in the cerebral sinuses area, Median=4, IQR=5. Clot burden in cerebral veins (p=.005) but not in cerebral sinuses, was associated with worse discharge mRS, r= .22. This effect remained significant when adjusting for age and gender (p=.002), but not when adjusting for complications including ICH, infarct, edema. Importantly, higher clot burden score in the cerebral veins predicted ICH (OR=1.73, p
Background: Anticoagulation is considered the first-line treatment for cerebral venous thrombosis... more Background: Anticoagulation is considered the first-line treatment for cerebral venous thrombosis (CVT). However, a subset of patients does not respond. Data from case studies suggest endovascular treatment (ET) may be beneficial in such cases. The Nationwide Inpatient Sample (NIS), representing a 20% stratified sample of 7 million annual hospital admissions was used to evaluate the safety and efficacy of ET compared to conservative management in CVT. Methods: We extracted cases from NIS database for years 2004-2013 using ICD 9-CM codes: 437.6, 325, and 671.5. Data related to mechanical thrombectomy (MT) and/or thrombolysis was searched using ICD 9 CPT codes 39.74 and 99.10. Weights were applied to each admission per NIS recommendations to obtain national representation. Groups were matched with respect to age, gender and Charlson index. Data was further adjusted for injury severity score (presence of ICH, stroke, paralysis, midline shift, coma, status epilepticus or need for intubation). Results: Out of 42,889 weighted estimates of CVT cases, 1058 (2%) received ET (616 cases of thrombolysis alone and 442 cases of MT +/- thrombolysis). Patients who received ET were slightly older with higher comorbidity score, and CVT associated complications including ischemic stroke, ICH, coma, status epilepticus, cerebral edema with midline shift and need for endotracheal intubation. Patients who received ET had higher likelihood of having hematological disorders and severe dehydration and lesser likelihood of infection and trauma as underlying etiology of the condition. ET (thrombolysis alone and mechanical thrombectomy +/- thrombolysis) appeared to be significantly associated mortality and bad discharge outcomes in stepwise logistic regression analyses as well as matched paired analyses (Table 1). Conclusion: ET appears to be associated with increased mortality and poor discharge outcomes when compared to conservative treatment in the real-world setting.
... 0 (no smiling) to 3 (large smile, with lips stretched, mouth open, the bulging of cheeks, and... more ... 0 (no smiling) to 3 (large smile, with lips stretched, mouth open, the bulging of cheeks, and the crin-kling of eyes). ... We thank Kate Nichols, Jennifer Voaklander, Lindsey Lange, Amanda Friesenborg, Michelle Martel, Amy Knaack, Alissa Chisholm, and many other students and ...
PDFTech ReportSPR 90-00-SLDR-010Traffic accidentsHuman factors in accidentsSleep deprivationAccid... more PDFTech ReportSPR 90-00-SLDR-010Traffic accidentsHuman factors in accidentsSleep deprivationAccident prone driversField testsAttentionMemoryFatigue (Physiological condition)United StatesIowa. Dept. of TransportationRizzo, MatthewTippin, JonAksan, NazanUniversity of Iowa Hospitals & Clinics. Dept. of NeurologyUnited States. Federal Highway AdministrationNTL-SAFETY AND SECURITY-AccidentsNTL-SAFETY AND SECURITY-Human FactorsUS Transportation CollectionExcessive daytime sleepiness underpins a large number of the reported motor vehicle crashes. Fair and accurate fieldmeasures are needed to identify at-risk drivers who have been identified as potentially driving in a sleep deprived state onthe basis of erratic driving behavior. The purpose of this research study was to evaluate a set of cognitive tests that canassist Motor Vehicle Enforcement Officers on duty in identifying drivers who may be engaged in sleep impaired driving.Currently no gold standard test exists to judge sleepiness in the field. Previous research has shown that PsychomotorVigilance Task (PVT) is sensitive to sleep deprivation. The first goal of the current study was to evaluate whethercomputerized tests of attention and memory, more brief than PVT, would be as sensitive to sleepiness effects. The secondgoal of the study was to evaluate whether objective and subjective indices of acute and cumulative sleepiness predictedcognitive performance. Findings showed that sleepiness effects were detected in three out of six tasks. Furthermore, PVTwas the only task that showed a consistent slowing of both \ue2\u20ac\u2dcbest\ue2\u20ac\u2122, i.e. minimum, and \ue2\u20ac\u2dctypical\ue2\u20ac\u2122 responses, median RT due tosleepiness. However, PVT failed to show significant associations with objective measures of sleep deprivation (number ofhours awake). The findings indicate that sleepiness tests in the field have significant limitations. The findings clearlyshow that it will not be possible to set absolute performance thresholds to identify sleep-impaired drivers based oncognitive performance on any test. Cooperation with industry to adjust work and rest cycles, and incentives to complywith those regulations will be critical components of a broad policy to prevent sleepy truck drivers from getting on theroad
Proceedings of the 7th International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design : driving assessment 2013, Oct 10, 2017
Background and Purpose: Obstruction of venous drainage may lead to venous hypertension, edema, in... more Background and Purpose: Obstruction of venous drainage may lead to venous hypertension, edema, infarction or intracerebral hemorrhage (ICH) in patients with cerebral venous thrombosis (CVST). While the presence of ICH and infarction are associated with worse outcomes, the independent effect of edema remains unknown. We aimed to evaluate the impact of the characteristics of brain edema on functional outcomes as measured by the modified Rankin Scale (mRS) at discharge. Methods: We retrospectively reviewed all patients who presented to the University of Iowa Health Care with CVST between 2004-2014. All patients received standard of care management per available AHA/ASA recommendations. Edema was categorized as focal vasogenic, focal cytotoxic or global cerebral edema (GCE). Vasogenic edema was described as hyperintensity on FLAIR MRI sequences around the location of venous clot while cytotoxic edema was noted when hyperintensities were visualized around the location of ICH/ venous infa...
Background and purpose: Unfractionated Heparin (UFH) infusion represents the most commonly used t... more Background and purpose: Unfractionated Heparin (UFH) infusion represents the most commonly used therapy in the acute management of cerebral venous sinus thrombosis (CVST). effectiveness of heparin in reaching therapeutic anti-coagulation levels has not been well studied in this population. Identifying subgroup of patients who will not respond to Heparin may prove useful in studying alternative treatments such as the new oral anticoagulants and endovascular therapy. We aimed to evaluate the initial response to heparin infusion measured by partial thromboplastin time (PTT) and it implication in discharge outcome. Methods: Retrospective review of all consecutive patients at University of Iowa Hospitals and Clinics between 2004-2014 with CVST was conducted. All patients were treated with initial weight based bolus (14units/kg) of UFH followed by infusion. Consecutive PTT values in the first 48hrs of admission were classified as either therapeutic (40-87), supra-therapeutic (>87), or ...
doi: 10.3389/fpsyg.2014.01288 Habituation of parasympathetic-mediated heart rate responses to rec... more doi: 10.3389/fpsyg.2014.01288 Habituation of parasympathetic-mediated heart rate responses to recurring acoustic startle
In this study, EEG (EEG-MPF, EEG-α/β), heart rate variability (RRV3), tracking error and subjecti... more In this study, EEG (EEG-MPF, EEG-α/β), heart rate variability (RRV3), tracking error and subjective rating of fatigue (drowsiness) while performing a simulated driving task were measured. The relation between these measurements and drowsiness was analyzed. As a result, EEG-MPF tended to decrease with the increase of drowsiness. It tended that EEG-α/β, RRV3 and tracking error increased with the increase of drowsiness. Then, a method for predicting drowsiness by applying Bayesian estimation to physiological measurements was proposed. Bayesian estimation carries out a statistical inference using some kind of evidences or observations and calculating the probability that a hypothesis is true. An attempt was made to predicting drowsiness by applying Bayesian estimation to psychological parameters such as EEG-MPF, EEG-α/β, RRV3. As a result, it was suggested that the proposed method can predict the symptom of decreased consciousness (drowsiness).
Proceedings of the 8th International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design: driving assessment 2015, 2015
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