Search

Background: Although magnetic resonance imaging, particularly diffusion-weighted imaging, has increasingly been used as part of a multimodal approach to prognostication in patients who are comatose after cardiac arrest, the performance of quantitative analysis of apparent diffusion coefficient (ADC) maps, as compared to standard radiologist impression, has not been well characterized. This retrospective study evaluated quantitative ADC analysis to the identification of anoxic brain injury by diffusion abnormalities on standard clinical magnetic resonance imaging reports.The cohort included 204 previously described comatose patients after cardiac arrest. Clinical outcome was assessed by (1) 3–6 month post-cardiac-arrest cerebral performance category and (2) coma recovery to following commands. Radiological evaluation was obtained from clinical reports and characterized as diffuse, cortex only, deep gray matter structures only, or no anoxic injury. Quantitative analyses of ADC maps were obtained in specific regions of interest (ROIs), whole cortex, and whole brain. A subgroup analysis of 172 was performed after eliminating images with artifacts and preexisting lesions.Radiological assessment outperformed quantitative assessment over all evaluated regions (area under the curve [AUC] 0.80 for radiological interpretation and 0.70 for the occipital region, the best performing ROI, p = 0.011); agreement was substantial for all regions. Radiological assessment still outperformed quantitative analysis in the subgroup analysis, though by smaller margins and with substantial to near-perfect agreement. When assessing for coma recovery only, the difference was no longer significant (AUC 0.83 vs. 0.81 for the occipital region, p = 0.70).Although quantitative analysis eliminates interrater differences in the interpretation of abnormal diffusion imaging and avoids bias from other prediction modalities, clinical radiologist interpretation has a higher predictive value for outcome. Agreement between radiological and quantitative analysis improved when using high-quality scans and when assessing for coma recovery using following commands. Quantitative assessment may thus be more subject to variability in both clinical management and scan quality than radiological assessment.Methods: Although magnetic resonance imaging, particularly diffusion-weighted imaging, has increasingly been used as part of a multimodal approach to prognostication in patients who are comatose after cardiac arrest, the performance of quantitative analysis of apparent diffusion coefficient (ADC) maps, as compared to standard radiologist impression, has not been well characterized. This retrospective study evaluated quantitative ADC analysis to the identification of anoxic brain injury by diffusion abnormalities on standard clinical magnetic resonance imaging reports.The cohort included 204 previously described comatose patients after cardiac arrest. Clinical outcome was assessed by (1) 3–6 month post-cardiac-arrest cerebral performance category and (2) coma recovery to following commands. Radiological evaluation was obtained from clinical reports and characterized as diffuse, cortex only, deep gray matter structures only, or no anoxic injury. Quantitative analyses of ADC maps were obtained in specific regions of interest (ROIs), whole cortex, and whole brain. A subgroup analysis of 172 was performed after eliminating images with artifacts and preexisting lesions.Radiological assessment outperformed quantitative assessment over all evaluated regions (area under the curve [AUC] 0.80 for radiological interpretation and 0.70 for the occipital region, the best performing ROI, p = 0.011); agreement was substantial for all regions. Radiological assessment still outperformed quantitative analysis in the subgroup analysis, though by smaller margins and with substantial to near-perfect agreement. When assessing for coma recovery only, the difference was no longer significant (AUC 0.83 vs. 0.81 for the occipital region, p = 0.70).Although quantitative analysis eliminates interrater differences in the interpretation of abnormal diffusion imaging and avoids bias from other prediction modalities, clinical radiologist interpretation has a higher predictive value for outcome. Agreement between radiological and quantitative analysis improved when using high-quality scans and when assessing for coma recovery using following commands. Quantitative assessment may thus be more subject to variability in both clinical management and scan quality than radiological assessment.Results: Although magnetic resonance imaging, particularly diffusion-weighted imaging, has increasingly been used as part of a multimodal approach to prognostication in patients who are comatose after cardiac arrest, the performance of quantitative analysis of apparent diffusion coefficient (ADC) maps, as compared to standard radiologist impression, has not been well characterized. This retrospective study evaluated quantitative ADC analysis to the identification of anoxic brain injury by diffusion abnormalities on standard clinical magnetic resonance imaging reports.The cohort included 204 previously described comatose patients after cardiac arrest. Clinical outcome was assessed by (1) 3–6 month post-cardiac-arrest cerebral performance category and (2) coma recovery to following commands. Radiological evaluation was obtained from clinical reports and characterized as diffuse, cortex only, deep gray matter structures only, or no anoxic injury. Quantitative analyses of ADC maps were obtained in specific regions of interest (ROIs), whole cortex, and whole brain. A subgroup analysis of 172 was performed after eliminating images with artifacts and preexisting lesions.Radiological assessment outperformed quantitative assessment over all evaluated regions (area under the curve [AUC] 0.80 for radiological interpretation and 0.70 for the occipital region, the best performing ROI, p = 0.011); agreement was substantial for all regions. Radiological assessment still outperformed quantitative analysis in the subgroup analysis, though by smaller margins and with substantial to near-perfect agreement. When assessing for coma recovery only, the difference was no longer significant (AUC 0.83 vs. 0.81 for the occipital region, p = 0.70).Although quantitative analysis eliminates interrater differences in the interpretation of abnormal diffusion imaging and avoids bias from other prediction modalities, clinical radiologist interpretation has a higher predictive value for outcome. Agreement between radiological and quantitative analysis improved when using high-quality scans and when assessing for coma recovery using following commands. Quantitative assessment may thus be more subject to variability in both clinical management and scan quality than radiological assessment.Conclusions: Although magnetic resonance imaging, particularly diffusion-weighted imaging, has increasingly been used as part of a multimodal approach to prognostication in patients who are comatose after cardiac arrest, the performance of quantitative analysis of apparent diffusion coefficient (ADC) maps, as compared to standard radiologist impression, has not been well characterized. This retrospective study evaluated quantitative ADC analysis to the identification of anoxic brain injury by diffusion abnormalities on standard clinical magnetic resonance imaging reports.The cohort included 204 previously described comatose patients after cardiac arrest. Clinical outcome was assessed by (1) 3–6 month post-cardiac-arrest cerebral performance category and (2) coma recovery to following commands. Radiological evaluation was obtained from clinical reports and characterized as diffuse, cortex only, deep gray matter structures only, or no anoxic injury. Quantitative analyses of ADC maps were obtained in specific regions of interest (ROIs), whole cortex, and whole brain. A subgroup analysis of 172 was performed after eliminating images with artifacts and preexisting lesions.Radiological assessment outperformed quantitative assessment over all evaluated regions (area under the curve [AUC] 0.80 for radiological interpretation and 0.70 for the occipital region, the best performing ROI, p = 0.011); agreement was substantial for all regions. Radiological assessment still outperformed quantitative analysis in the subgroup analysis, though by smaller margins and with substantial to near-perfect agreement. When assessing for coma recovery only, the difference was no longer significant (AUC 0.83 vs. 0.81 for the occipital region, p = 0.70).Although quantitative analysis eliminates interrater differences in the interpretation of abnormal diffusion imaging and avoids bias from other prediction modalities, clinical radiologist interpretation has a higher predictive value for outcome. Agreement between radiological and quantitative analysis improved when using high-quality scans and when assessing for coma recovery using following commands. Quantitative assessment may thus be more subject to variability in both clinical management and scan quality than radiological assessment. [ABSTRACT FROM AUTHOR]

Therapeutic hypothermia (TH) is a neuroprotective treatment post-cardiac arrest but is grossly underutilized. After TH induction, traditional biomarkers and parameters can no long predict clinical outcome due to a lack of understanding of hypothermic response. Innovative approaches to better understand the clinical effect of TH will help to prognosticate outcome and expand beneficial population. Protein glycosylation is an important extracellular post-translational modification, regulating various extracellular signaling pathways. Here, we used glycoproteomics to investigate the association of plasma glycoproteins with the prognosis of TH-treated cardiac arrest patients. Using lectin affinity chromatography and mass spectrometry, we identified 640 glycoproteins in the plasma of cardiac arrest patients undergoing TH treatment, of which 23 were up-regulated and 14 were down-regulated in good outcome patients as compared with poor outcome ones. Notably, two glycoproteins with antioxidant activity, ceruloplasmin (CP) and haptoglobin (HP), were found to be associated with favorable neurologic outcome. This was further supported by ELISA assay in a large patients cohort, in which glycosylated CP and HP enriched by concanavilin A (ConA) and wheat germ agglutinin (WGA) lectins were significantly increased in patients developing good outcome (ConA-CP: p = 0.033; ConA-HP: p = 0.04; WGA-HP: p = 0.021). Furthermore, ROC analysis demonstrated the predictive potential of ConA-CP, ConA-HP, and WGA-HP (ConA-CP: AUC = 0.732, p = 0.031; ConA-HP: AUC = 0.746, p = 0.022; WGA-HP: AUC = 0.714, p = 0.046) and combination of them improved the predictive power (AUC = 0.830, p = 0.002). Our results suggested that glycosylated CP and HP as well as other glycoproteins may play critical roles in neuroprotection and serve as sensitive prognostic markers for TH treatments. [ABSTRACT FROM AUTHOR]

Cardiac arrest is the most common cause of death in North America. An organized bundle of neurocritical care interventions can improve chances of survival and neurological recovery in patients who are successfully resuscitated from cardiac arrest. Therefore, resuscitation following cardiac arrest was chosen as an Emergency Neurological Life Support protocol. Key aspects of successful early post-arrest management include: prevention of secondary brain injury; identification of treatable causes of arrest in need of emergent intervention; and, delayed neurological prognostication. Secondary brain injury can be attenuated through targeted temperature management (TTM), avoidance of hypoxia and hypotension, avoidance of hyperoxia, hyperventilation or hypoventilation, and treatment of seizures. Most patients remaining comatose after resuscitation from cardiac arrest should undergo TTM. Treatable precipitants of arrest that require emergent intervention include, but are not limited to, acute coronary syndrome, intracranial hemorrhage, pulmonary embolism and major trauma. Accurate neurological prognostication is generally not appropriate for several days after cardiac arrest, so early aggressive care should never be limited based on perceived poor neurological prognosis. [ABSTRACT FROM AUTHOR]

Background: Existing studies of quantitative electroencephalography (qEEG) as a prognostic tool after cardiac arrest (CA) use methods that ignore the longitudinal pattern of qEEG data, resulting in significant information loss and precluding analysis of clinically important temporal trends. We tested the utility of group-based trajectory modeling (GBTM) for qEEG classification, focusing on the specific example of suppression ratio (SR).Methods: We included comatose CA patients hospitalized from April 2010 to October 2014, excluding CA from trauma or neurological catastrophe. We used Persyst®v12 to generate SR trends and used semi-quantitative methods to choose appropriate sampling and averaging strategies. We used GBTM to partition SR data into different trajectories and regression associate trajectories with outcome. We derived a multivariate logistic model using clinical variables without qEEG to predict survival, then added trajectories and/or non-longitudinal SR estimates, and assessed changes in model performance.Results: Overall, 289 CA patients had ≥36 h of EEG yielding 10,404 h of data (mean age 57 years, 81 % arrested out-of-hospital, 33 % shockable rhythms, 31 % overall survival, 17 % discharged to home or acute rehabilitation). We identified 4 distinct SR trajectories associated with survival (62, 26, 12, and 0 %, P < 0.0001 across groups) and CPC (35, 10, 4, and 0 %, P < 0.0001 across groups). Adding trajectories significantly improved model performance compared to adding non-longitudinal data.Conclusions: Longitudinal analysis of continuous qEEG data using GBTM provides more predictive information than analysis of qEEG at single time-points after CA. [ABSTRACT FROM AUTHOR]

Complications involving the central and peripheral nervous system are frequently encountered in critically ill patients. All components of the neuraxis can be involved including the brain, spinal cord, peripheral nerves, neuromuscular junction, and muscles. Neurologic complications adversely impact outcome and length of stay. These complications can be related to underlying critical illness, pre-existing comorbid conditions, and commonly used and life-saving procedures and medications. Familiarity with the myriad neurologic complications that occur in the intensive care unit can facilitate their timely recognition and treatment. Additionally, awareness of treatment-related neurologic complications may inform decision-making, mitigate risk, and improve outcomes. [ABSTRACT FROM AUTHOR]

Objective: Intrathecal baclofen therapy (ITB) has been used in the treatment of spasticity and dystonia. In our pediatric movement disorder clinic, we noted a delay in referral of patients for consideration of ITB. Often, only after years of failed medical therapy, a baclofen pump is considered. This study attempts to investigate the prevalence, length and causes of the delay. Methods: A retrospective, outcome analysis was performed. We conducted a survey of 30 pediatric patients who received baclofen pumps between the ages of 5 and 23. Patients were divided into two groups (before and after ITB approval by the US Food and Drug Administration in 1996) (FDA/Center for Drug Evaluation and Research, ; Ridley and Rawlins, J Neurosci Nurs 38:72-82, ; Medical Advisory Secretariat, Ont Health Technol Assess Ser 5:1-93, ). Information was collected regarding their onset of spasticity, attempted treatments, pump referral, satisfaction, and resulting change in the quality of life. Results: There was a delay in referral in most cases investigated. Average time to baclofen pump implantation, after initial onset of spasticity, was 5.14 years (group A) and 11.7 years (group B). Out of the subjects who reported diminished effects or no effect of pharmacological treatment, 93 % of these respondents reported that ITB had a dramatic long-lasting effect on their spasticity. Of 30 patients, 28 reported effectiveness of ITB, and 26 of 30 subjects reported an improved quality and ease of life. Conclusion: Despite the limitations of this subjective retrospective analysis of outcomes and delay in referral, the opinions of the parents and caregivers should be considered. Earlier referral for ITB therapy may better treat severe spasticity in pediatric patients. [ABSTRACT FROM AUTHOR]

A major challenge in the diagnosis of disorders of consciousness is the differential diagnosis between the vegetative state (VS) and the minimally conscious state (MCS). Clinically, VS is defined by complete unawareness, whereas MCS is defined by the presence of inconsistent but clearly discernible behavioural signs of consciousness. In healthy individuals, pain cries have been reported to elicit functional activation within the pain matrix of the brain, which may be interpreted as empathic reaction. In this study, pain cries were presented to six VS patients, six MCS patients, and 17 age-matched healthy controls. Conventional task-related functional magnetic resonance imaging (fMRI) showed no significant differences in functional activation between the VS and MCS groups. In contrast to this negative finding, the application of a novel data-driven technique for the analysis of the brain's global functional connectivity yielded a positive result. The weighted global connectivity (WGC) was significantly greater in the MCS group compared to the VS group ( p < 0.05, family-wise error corrected). Using areas of significant WGC differences as 'seed regions' in a secondary connectivity analysis revealed extended functional networks in both MCS and healthy groups, whereas no such long-range functional connections were observed in the VS group. These results demonstrate the potential of functional connectivity MRI (fcMRI) as a clinical tool for differential diagnosis in disorders of consciousness. [ABSTRACT FROM AUTHOR]

Background: Therapeutic hypothermia (TH) improves outcomes in comatose patients resuscitated from cardiac arrest. However, nonconvulsive status epilepticus (NCSE) may cause persistent coma. The frequency and timing of NCSE after cardiac arrest is unknown. Methods: Review of consecutive subjects treated with TH and receiving continuous EEG (cEEG) monitoring between 8/1/2009 and 11/16/2010. Demographic data, survival, and functional outcome were prospectively recorded. Each cEEG file was analyzed using standard definitions to define NCSE. Data were analyzed using descriptive and nonparametric statistics. Results: Mean age of the 101 subjects was 57 years (SD 15) with most subjects being male ( N = 55, 54%) and experiencing out-of-hospital cardiac arrest ( N = 78; 77%). Ventricular fibrillation was the initial cardiac rhythm in 39 (38%). All subjects received TH. Thirty subjects (30%) awoke at a median of 41 h (IQR 30, 61) after cardiac arrest. A total of 29/30 (97%) subjects surviving to hospital discharge were awake. Median interval from arrest to placement of cEEG was 9 h (IQR 6, 12), at which time the mean temperature was 33.9°C. NCSE occurred in 12 (12%) subjects. In 3/12 (25%) subjects, NCSE was present when the cEEG recording began. In 4 subjects, NCSE occurred within 8 h of cEEG recording. One (8%) subject with NCSE survived in a vegetative state. Conclusions: NCSE is common in comatose post-cardiac arrest subjects receiving TH. Most seizures occur within the first 8 h of cEEG recording and within the first 12 h after resuscitation from cardiac arrest. Outcomes are poor in those who experience NCSE. [ABSTRACT FROM AUTHOR]

Anoxic brain injury is a common outcome after cardiac arrest. Despite substantial research into the pathophysiology and management of this injury, a beneficial treatment modality has not been previously identified. Recent studies show that induced hypothermia reduces mortality and improves neurological outcomes in patients resuscitated from ventricular fibrillation. This article reviews the literature on induced hypothermia for anoxic brain injury and summarizes a treatment algorithm proposed by the Canadian Association of Emergency Physicians Critical Care Committee for hypothermia induction in cardiac arrest survivors. [ABSTRACT FROM AUTHOR]

Background: Plantar flexion with plantar stimulation has been well described in brain death, and is compatible with brain death. However, plantar flexion with stimulation to the dorsal surface of the foot has not been reported previously in brain dead patients. Methods: Case report with Technetium-99 m hexamethylpropyleneamine oxime brain scan and video. Results: A 46-year-old woman suffered severe anoxic brain injury following massive pulmonary embolism 5 days after arthroscopic knee surgery. Neurologic examination was consistent with brain death, with the exception of plantar flexion when noxious stimulation was applied to the dorsal surface of the great toe on each side. Ancillary testing with a technetium-99 m nuclear scan demonstrated absence of cerebral perfusion, supporting the diagnosis of brain death. Conclusions: Noxious stimulation to the dorsal surface of the foot may trigger spinally mediated plantar flexion in patients with brain death. [ABSTRACT FROM AUTHOR]

An 18-year-old boy with anoxic brain injury, suffering from severe psychomotor inhibition, tetrarigidity and dystonia, was treated with amantadine in order to ameliorate his symptoms. Neuropsychological tests showed improvement in motor and cognitive functions. [ABSTRACT FROM AUTHOR]