G Chaitanya1, A Arivazhagan2, S Sinha3, K R Madhusudan Reddy4, K Thennarasu5, R D Bharath6, M Bhaskara Rao7, B A Chandramouli7, P Satishchandra3. 1. Department of Clinical Neuroscience, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India; Department of Neurology, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India. 2. Department of Neurosurgery, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India. Electronic address: arivazhagan.a@gmail.com. 3. Department of Neurology, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India. 4. Department of Neuro Anesthesiology, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India. 5. Department of Biostatistics, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India. 6. Department of Neuroimaging and Interventional Radiology, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India. 7. Department of Neurosurgery, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India.
Abstract
BACKGROUND: Anesthetic-induced suppression of cortical electrical activity is a major concern during epilepsy surgery. Dexmedetomidine (Dex) has been recently evaluated in a few small series for its effect on the electrocorticographic spikes intra-operatively. METHODS: In this prospective study, electrocorticogram (ECoG) was monitored during dexmedetomidine infusion in 34 patients (M:F=23:11, age=29.2 ± 10.9 years; duration of epilepsy=15.3 ± 8.9 years) undergoing anterior temporal lobe resection with amygdalo-hippocampectomy for drug-resistant mesial temporal lobe epilepsy (Right: 18, Left: 16). Anesthesia was induced with thiopental/propofol and maintained with oxygen-N2O-isoflurane. ECoG was recorded for 5 min after the end tidal MAC of N2O and isoflurane were decreased to zero; anesthesia was maintained with O2:Air=50:50, vecuronium and fentanyl. ECoG was recorded using a 4-contact strip electrode for: (a) 5 min prior to dexmedetomidine (PreDEX), (b) 5 min during dexmedetomidine infusion (DEX; 1 μg/kg) and (c) 5 min after stopping dexmedetomidine (PostDEX). RESULTS: The ECoG spikes were manually counted in all the channels. The mean spike rate in the 2 channels with maximum spikes (MAX CH A and MAX CH B) was normalized to a 3-min duration. RM-ANOVA and post hoc comparison of three phases were used to compare the spike rates. The mean spike rate during Dex phase was higher compared to preDEX (MAX CH B: p=0.007 and MAX CH A: p=0.079) and PostDEX (MAX CH B: p=0.17, MAX CH A: p=0.79) phases. The spike rate increased in 67.6% patients, while 11.8% patients showed ≤ 25% reduction and 20.6% patients showed >25% reduction in spike frequency. CONCLUSION: Dexmedetomidine is useful during intra-operative ECoG recording in epilepsy surgery as it enhances or does not alter spike rate in most of the cases, without any major adverse effects.
BACKGROUND: Anesthetic-induced suppression of cortical electrical activity is a major concern during epilepsy surgery. Dexmedetomidine (Dex) has been recently evaluated in a few small series for its effect on the electrocorticographic spikes intra-operatively. METHODS: In this prospective study, electrocorticogram (ECoG) was monitored during dexmedetomidine infusion in 34 patients (M:F=23:11, age=29.2 ± 10.9 years; duration of epilepsy=15.3 ± 8.9 years) undergoing anterior temporal lobe resection with amygdalo-hippocampectomy for drug-resistant mesial temporal lobe epilepsy (Right: 18, Left: 16). Anesthesia was induced with thiopental/propofol and maintained with oxygen-N2O-isoflurane. ECoG was recorded for 5 min after the end tidal MAC of N2O and isoflurane were decreased to zero; anesthesia was maintained with O2:Air=50:50, vecuronium and fentanyl. ECoG was recorded using a 4-contact strip electrode for: (a) 5 min prior to dexmedetomidine (PreDEX), (b) 5 min during dexmedetomidine infusion (DEX; 1 μg/kg) and (c) 5 min after stopping dexmedetomidine (PostDEX). RESULTS: The ECoG spikes were manually counted in all the channels. The mean spike rate in the 2 channels with maximum spikes (MAX CH A and MAX CH B) was normalized to a 3-min duration. RM-ANOVA and post hoc comparison of three phases were used to compare the spike rates. The mean spike rate during Dex phase was higher compared to preDEX (MAX CH B: p=0.007 and MAX CH A: p=0.079) and PostDEX (MAX CH B: p=0.17, MAX CH A: p=0.79) phases. The spike rate increased in 67.6% patients, while 11.8% patients showed ≤ 25% reduction and 20.6% patients showed >25% reduction in spike frequency. CONCLUSION:Dexmedetomidine is useful during intra-operative ECoG recording in epilepsy surgery as it enhances or does not alter spike rate in most of the cases, without any major adverse effects.
Authors: Thomas Parmentier; Gabrielle Monteith; Miguel A Cortez; Franziska Wielaender; Andrea Fischer; Tarja S Jokinen; Hannes Lohi; Sean Sanders; Veronique Sammut; Tricia Tai; Fiona M K James Journal: J Vet Intern Med Date: 2020-07-13 Impact factor: 3.333