The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Geoffrey K Isbister - One of the best experts on this subject based on the ideXlab platform.
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tramadol overdose causes seizures and respiratory depression but serotonin toxicity appears unlikely
Clinical Toxicology, 2015Co-Authors: Nicole M Ryan, Geoffrey K IsbisterAbstract:AbstractContext. Tramadol is a commonly used centrally acting analgesic associated with seizures and suspected to cause serotonin toxicity in overdose. Objective. This study sought to investigate the effects of tramadol overdose, and included evaluation for serotonin toxicity based on the Hunter Serotonin Toxicity Criteria where the seven clinical features of spontaneous Clonus, inducible Clonus, ocular Clonus, agitation, diaphoresis, tremor and hyperreflexia are examined for in all patients taking serotonergic medications; seizures and central nervous system depression. Materials and methods. This was an observational cases series based on a retrospective review of tramadol overdoses (> 400 mg) admitted to a tertiary toxicology unit from November 2000 to June 2013. Demographic details, information on ingestion (dose and co-ingestants), clinical effects, complications (seizures, serotonin toxicity and cardiovascular effects) and intensive care unit (ICU) admission were extracted from a clinical database. ...
Christine K. Thomas - One of the best experts on this subject based on the ideXlab platform.
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characteristics of lower extremity Clonus after human cervical spinal cord injury
Journal of Neurotrauma, 2012Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Clonus can interfere with self-care and rehabilitation of people with spinal cord injury. Our aim was to characterize Clonus and to evaluate factors that influence Clonus duration in muscles paralyzed chronically by spinal cord injury. Electromyographic activity was recorded from soleus and 7 other limb muscles (5 ipsilateral, 2 contralateral) during Clonus. In 14 subjects, Clonus frequency in soleus averaged 5.4±0.9 Hz and was slower when the reflex path was longer. Contraction frequency slowed at the beginning and end of Clonus (sometimes by 2 Hz). The magnitude of one cycle changed the timing and magnitude of the next cycle. These data suggest that afferent input influences the frequency and maintenance of Clonus. Recording from many muscles revealed that Clonus was prolonged (>40 sec) when only ipsilateral triceps surae or triceps surae and tibialis anterior were involved. Therefore, localized inputs to spinal circuits were important to sustain Clonus. Clonus was intermediate (median: 21 sec) with activation of three or four ipsilateral muscles and these contractions were associated with greater activation of ipsilateral flexors. Clonus was short (<5 sec) when ipsilateral and contralateral muscles were activated (five or six muscles). Activation of extraneous afferent input, particularly contralateral muscles, may provide a way to shorten Clonus after spinal cord injury.
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Characteristics of lower extremity Clonus after human cervical spinal cord injury.
Journal of Neurotrauma, 2011Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Clonus can interfere with self-care and rehabilitation of people with spinal cord injury. Our aim was to characterize Clonus and to evaluate factors that influence Clonus duration in muscles paralyzed chronically by spinal cord injury. Electromyographic activity was recorded from soleus and 7 other limb muscles (5 ipsilateral, 2 contralateral) during Clonus. In 14 subjects, Clonus frequency in soleus averaged 5.4±0.9 Hz and was slower when the reflex path was longer. Contraction frequency slowed at the beginning and end of Clonus (sometimes by 2 Hz). The magnitude of one cycle changed the timing and magnitude of the next cycle. These data suggest that afferent input influences the frequency and maintenance of Clonus. Recording from many muscles revealed that Clonus was prolonged (>40 sec) when only ipsilateral triceps surae or triceps surae and tibialis anterior were involved. Therefore, localized inputs to spinal circuits were important to sustain Clonus. Clonus was intermediate (median: 21 sec) with activation of three or four ipsilateral muscles and these contractions were associated with greater activation of ipsilateral flexors. Clonus was short (
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Automatic analysis of EMG during Clonus.
Journal of Neuroscience Methods, 2011Co-Authors: Chaithanya Krishna Mummidisetty, Jorge Bohorquez, Christine K. ThomasAbstract:Clonus can disrupt daily activities after spinal cord injury. Here an algorithm was developed to automatically detect contractions during Clonus in 24-hour electromyographic (EMG) records. Filters were created by non-linearly scaling a Mother (Morlet) wavelet to envelope the EMG using different frequency bands. The envelope for the intermediate band followed the EMG best (74.8–193.9 Hz). Threshold and time constraints were used to reduce the envelope peaks to one per contraction. Energy in the EMG was measured 50 ms either side of each envelope (contraction) peak. Energy values at 5 % and 95 % maximal defined EMG start and end time, respectively. The algorithm was as good as a person at identifying contractions during Clonus (p = 0.946, n=31 spasms, 7 subjects with cervical spinal cord injury), and marking start and end times to determine Clonus frequency (intra class correlation coefficient, α: 0.949), contraction intensity using root mean square EMG (α: 0.997) and EMG duration (α: 0.852). On average the algorithm was 574 times faster than manual analysis performed independently by two people (p≤ 0.001). This algorithm is an important tool for characterization of Clonus in long-term EMG records.
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motor unit behavior during Clonus
Journal of Applied Physiology, 2005Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Medial gastrocnemius surface electromyographic activity and intramuscular electromyographic activity were recorded from six individuals with chronic cervical spinal cord injury to document the recr...
Nicole M Ryan - One of the best experts on this subject based on the ideXlab platform.
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tramadol overdose causes seizures and respiratory depression but serotonin toxicity appears unlikely
Clinical Toxicology, 2015Co-Authors: Nicole M Ryan, Geoffrey K IsbisterAbstract:AbstractContext. Tramadol is a commonly used centrally acting analgesic associated with seizures and suspected to cause serotonin toxicity in overdose. Objective. This study sought to investigate the effects of tramadol overdose, and included evaluation for serotonin toxicity based on the Hunter Serotonin Toxicity Criteria where the seven clinical features of spontaneous Clonus, inducible Clonus, ocular Clonus, agitation, diaphoresis, tremor and hyperreflexia are examined for in all patients taking serotonergic medications; seizures and central nervous system depression. Materials and methods. This was an observational cases series based on a retrospective review of tramadol overdoses (> 400 mg) admitted to a tertiary toxicology unit from November 2000 to June 2013. Demographic details, information on ingestion (dose and co-ingestants), clinical effects, complications (seizures, serotonin toxicity and cardiovascular effects) and intensive care unit (ICU) admission were extracted from a clinical database. ...
Douglas M. Wallace - One of the best experts on this subject based on the ideXlab platform.
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characteristics of lower extremity Clonus after human cervical spinal cord injury
Journal of Neurotrauma, 2012Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Clonus can interfere with self-care and rehabilitation of people with spinal cord injury. Our aim was to characterize Clonus and to evaluate factors that influence Clonus duration in muscles paralyzed chronically by spinal cord injury. Electromyographic activity was recorded from soleus and 7 other limb muscles (5 ipsilateral, 2 contralateral) during Clonus. In 14 subjects, Clonus frequency in soleus averaged 5.4±0.9 Hz and was slower when the reflex path was longer. Contraction frequency slowed at the beginning and end of Clonus (sometimes by 2 Hz). The magnitude of one cycle changed the timing and magnitude of the next cycle. These data suggest that afferent input influences the frequency and maintenance of Clonus. Recording from many muscles revealed that Clonus was prolonged (>40 sec) when only ipsilateral triceps surae or triceps surae and tibialis anterior were involved. Therefore, localized inputs to spinal circuits were important to sustain Clonus. Clonus was intermediate (median: 21 sec) with activation of three or four ipsilateral muscles and these contractions were associated with greater activation of ipsilateral flexors. Clonus was short (<5 sec) when ipsilateral and contralateral muscles were activated (five or six muscles). Activation of extraneous afferent input, particularly contralateral muscles, may provide a way to shorten Clonus after spinal cord injury.
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Characteristics of lower extremity Clonus after human cervical spinal cord injury.
Journal of Neurotrauma, 2011Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Clonus can interfere with self-care and rehabilitation of people with spinal cord injury. Our aim was to characterize Clonus and to evaluate factors that influence Clonus duration in muscles paralyzed chronically by spinal cord injury. Electromyographic activity was recorded from soleus and 7 other limb muscles (5 ipsilateral, 2 contralateral) during Clonus. In 14 subjects, Clonus frequency in soleus averaged 5.4±0.9 Hz and was slower when the reflex path was longer. Contraction frequency slowed at the beginning and end of Clonus (sometimes by 2 Hz). The magnitude of one cycle changed the timing and magnitude of the next cycle. These data suggest that afferent input influences the frequency and maintenance of Clonus. Recording from many muscles revealed that Clonus was prolonged (>40 sec) when only ipsilateral triceps surae or triceps surae and tibialis anterior were involved. Therefore, localized inputs to spinal circuits were important to sustain Clonus. Clonus was intermediate (median: 21 sec) with activation of three or four ipsilateral muscles and these contractions were associated with greater activation of ipsilateral flexors. Clonus was short (
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motor unit behavior during Clonus
Journal of Applied Physiology, 2005Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Medial gastrocnemius surface electromyographic activity and intramuscular electromyographic activity were recorded from six individuals with chronic cervical spinal cord injury to document the recr...
Bruce H. Ross - One of the best experts on this subject based on the ideXlab platform.
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characteristics of lower extremity Clonus after human cervical spinal cord injury
Journal of Neurotrauma, 2012Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Clonus can interfere with self-care and rehabilitation of people with spinal cord injury. Our aim was to characterize Clonus and to evaluate factors that influence Clonus duration in muscles paralyzed chronically by spinal cord injury. Electromyographic activity was recorded from soleus and 7 other limb muscles (5 ipsilateral, 2 contralateral) during Clonus. In 14 subjects, Clonus frequency in soleus averaged 5.4±0.9 Hz and was slower when the reflex path was longer. Contraction frequency slowed at the beginning and end of Clonus (sometimes by 2 Hz). The magnitude of one cycle changed the timing and magnitude of the next cycle. These data suggest that afferent input influences the frequency and maintenance of Clonus. Recording from many muscles revealed that Clonus was prolonged (>40 sec) when only ipsilateral triceps surae or triceps surae and tibialis anterior were involved. Therefore, localized inputs to spinal circuits were important to sustain Clonus. Clonus was intermediate (median: 21 sec) with activation of three or four ipsilateral muscles and these contractions were associated with greater activation of ipsilateral flexors. Clonus was short (<5 sec) when ipsilateral and contralateral muscles were activated (five or six muscles). Activation of extraneous afferent input, particularly contralateral muscles, may provide a way to shorten Clonus after spinal cord injury.
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Characteristics of lower extremity Clonus after human cervical spinal cord injury.
Journal of Neurotrauma, 2011Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Clonus can interfere with self-care and rehabilitation of people with spinal cord injury. Our aim was to characterize Clonus and to evaluate factors that influence Clonus duration in muscles paralyzed chronically by spinal cord injury. Electromyographic activity was recorded from soleus and 7 other limb muscles (5 ipsilateral, 2 contralateral) during Clonus. In 14 subjects, Clonus frequency in soleus averaged 5.4±0.9 Hz and was slower when the reflex path was longer. Contraction frequency slowed at the beginning and end of Clonus (sometimes by 2 Hz). The magnitude of one cycle changed the timing and magnitude of the next cycle. These data suggest that afferent input influences the frequency and maintenance of Clonus. Recording from many muscles revealed that Clonus was prolonged (>40 sec) when only ipsilateral triceps surae or triceps surae and tibialis anterior were involved. Therefore, localized inputs to spinal circuits were important to sustain Clonus. Clonus was intermediate (median: 21 sec) with activation of three or four ipsilateral muscles and these contractions were associated with greater activation of ipsilateral flexors. Clonus was short (
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motor unit behavior during Clonus
Journal of Applied Physiology, 2005Co-Authors: Douglas M. Wallace, Bruce H. Ross, Christine K. ThomasAbstract:Medial gastrocnemius surface electromyographic activity and intramuscular electromyographic activity were recorded from six individuals with chronic cervical spinal cord injury to document the recr...