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Background: Antiepileptic drugs decrease the intensity of the effect of neuromuscular blocking agents. The objective of this study was to evaluate the influence of chronic phenytoin therapy (CPT) on the pharmacokinetics (PK) and pharmacodynamics (PD) of rocuronium. Methods: A total of 21 patients undergoing intracranial surgery were enrolled in the study. Ten of these were under CPT. Rocuronium was administered intravenously. Arterial blood samples were drawn, and the T1% (percentage change from the response to the supramaximal stimulus) derived from electromyogram was continuously recorded. NONMEM software was used to construct, evaluate and validate the PKPD models. Results: The PKPD of rocuronium was described using a three-compartment PK model and effect compartment model. The CPT therapy was found to increase the total plasma clearance from 0.26 to 0.75 L min-1. The PD model parameter estimates were ke0= 0.073 min-1, IC50 (the steady-state plasma concentration eliciting half of the maximum response) = 836 ng mL-1 and [gamma] = 3.13. Conclusions: Chronic phenytoin therapy increases the clearance of rocuronium from 0.26 to 0.75 L min-1 but has no effect on the ke0, IC50 or [gamma] parameters. [ABSTRACT FROM AUTHOR]

Background: Perioperative cognitive dysfunction (PCD) is a very prevalent clinical syndrome due to the progressive aging of the surgical population.The aim of our study is to evaluate the clinical practice of Spanish anesthesiologists surveyed regarding this entity., Material and Methods: Prospective online survey conducted by the Neurosciences Section and distributed by SEDAR., Results: 544 responses were obtained, with a participation rate of 17%. 54.4% of respondents never make a preoperative assessment of cognitive impairment, only 7.5% always do it. 79.6% lack an intraoperative management protocol for the patient at risk of PCD. In the anesthetic planning, only 23.3% of the patients was kept in mind. Eighty-nine percent considered regional anesthesia with or without sedation preferable to general anesthesia for the prevention of PCD. 88.8% considered benzodiazepines to present a high risk of PCD. 71.7% considered that anesthetic depth monitoring could prevent postoperative cognitive deficit. Routine evaluation of postoperative delirium is low, only 14%. More than 80% recognize that PCD is underdiagnosed., Conclusions: Among Spanish anesthesiologists surveyed, PCD is still a little known and underappreciated entity. It is necessary to raise awareness of the need to detect risk factors for PCD, as well as postoperative assessment and diagnosis. Therefore, the development of guidelines and protocols and the implementation of continuing education programs in which anesthesiologists should be key members of multidisciplinary teams in charge of perioperative care are suggested., (Copyright © 2024 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.)

Background: The safety of anaesthesia has improved as a result of better control of anaesthetic depth. However, conventional monitoring does not inform on the nature of nociceptive processes during unconsciousness. A means of inferring the quality of potentially painful experiences could derive from analysis of brain activity using neuroimaging. We have evaluated the dose effects of remifentanil on brain response to noxious stimuli during deep sedation and spontaneous breathing., Methods: Optimal data were obtained in 26 healthy subjects. Pressure stimulation that proved to be moderately painful before the experiment was applied to the thumbnail. Functional MRI was acquired in 4-min periods at low (0.5 ng ml -1 ), medium (1 ng ml -1 ), and high (1.5 ng ml -1 ) target plasma concentrations of remifentanil at a stable background infusion of propofol adjusted to induce a state of light unconsciousness., Results: At low remifentanil doses, we observed partial activation in brain areas processing sensory-discriminative and emotional-affective aspects of pain. At medium doses, relevant changes were identified in structures highly sensitive to general brain arousal, including the brainstem, cerebellum, thalamus, auditory and visual cortices, and the frontal lobe. At high doses, no significant activation was observed., Conclusions: The response to moderately intense focal pressure in pain-related brain networks is effectively eliminated with safe remifentanil doses. However, the safety margin in deep sedation-analgesia would be narrowed in minimising not only nociceptive responses, but also arousal-related biological stress., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

After falling asleep, the brain needs to detach from waking activity and reorganize into a functionally distinct state. A functional MRI (fMRI) study has recently revealed that the transition to unconsciousness induced by propofol involves a global decline of brain activity followed by a transient reduction in cortico-subcortical coupling. We have analyzed the relationships between transitional brain activity and breathing changes as one example of a vital function that needs the brain to readapt. Thirty healthy participants were originally examined. The analysis involved the correlation between breathing and fMRI signal upon loss of consciousness. We proposed that a decrease in ventilation would be coupled to the initial decline in fMRI signal in brain areas relevant for modulating breathing in the awake state, and that the subsequent recovery would be coupled to fMRI signal in structures relevant for controlling breathing during the unconscious state. Results showed that a slight reduction in breathing from wakefulness to unconsciousness was distinctively associated with decreased activity in brain systems underlying different aspects of consciousness including the prefrontal cortex, the default mode network and somatosensory areas. Breathing recovery was distinctively coupled to activity in deep brain structures controlling basic behaviors such as the hypothalamus and amygdala. Activity in the brainstem, cerebellum and hippocampus was associated with breathing variations in both states. Therefore, our brain maps illustrate potential drives to breathe, unique to wakefulness, in the form of brain systems underlying cognitive awareness, self-awareness and sensory awareness, and to unconsciousness involving structures controlling instinctive and homeostatic behaviors., Competing Interests: Declaration of Competing Interest The authors report no financial interests or potential conflicts of interest., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Dexmedetomidine is used as adjuvant in total intravenous anaesthesia (TIVA), but there have been few studies concerning its effect on intraoperative neurophysiological monitoring (IONM) during cranial surgery. Our aim was to study the effect of dexmedetomidine on IONM in patients undergoing brain stem and supratentorial cranial surgery., Methods: Two prospective, randomized, double-blind substudies were conducted. In substudy 1, during TIVA with an infusion of propofol and remifentanil, 10 patients received saline solution (SS) (PR group) and another 10 (PRD group) received dexmedetomidine (0.5 mcg/kg/h). Total dosage of propofol and remifentanil, intensity, latency and amplitude of motor-evoked potentials following transcranial electrical stimulation (tcMEPs) as well as somatosensory-evoked potentials (SSEP) were recorded at baseline, 15, 30, 45 minutes, and at the end of surgery. In order to identify differences in the same patient after dexmedetomidine administration, we designed substudy 2 with 20 new patients randomized to two groups. After 30 minutes with TIVA, 10 patients received dexmedetomidine (0.5 mcg/kg/h) and 10 patients SS. The same variables were recorded., Results: In substudy 1, propofol requirements were significantly lower (P = .004) and tcMEP intensity at the end of surgery was significantly higher in PRD group, but no statistically significant differences were observed for remifentanil requirements, SSEP and tcMEP latency or amplitude. In substudy 2, no differences in any of the variables were identified., Conclusions: The administration of dexmedetomidine at a dosage of 0.5 mg/kg/h may reduce propofol requirements and adversely affect some neuromonitoring variables. However, it can be an alternative on IONM during cranial surgeries. REDEX EudraCT: 2014-000962-23., (© 2021 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

The brain is a functional unit made up of multilevel connected elements showing a pattern of synchronized activity that varies in different states. The wake-sleep cycle is a major variation of brain functional condition that is ultimately regulated by subcortical arousal- and sleep-promoting cell groups. We analyzed the evolution of functional MRI (fMRI) signal in the whole cortex and in a deep region including most sleep- and wake-regulating subcortical nuclei at loss of consciousness induced by the hypnotic agent propofol. Optimal data were obtained in 21 of the 30 healthy participants examined. A dynamic analysis of fMRI time courses on a time-scale of seconds was conducted to characterize consciousness transition, and functional connectivity maps were generated to detail the anatomy of structures showing different dynamics. Inside the magnet, loss of consciousness was marked by the participants ceasing to move their hands. We observed activity synchronization after loss of consciousness within both the cerebral cortex and subcortical structures. However, the evolution of fMRI signal was dissociated, showing a transient reduction of global cortico-subcortical coupling that was restored during the unconscious state. An exception to cortico-subcortical decoupling was a brain network related to self-awareness (i.e. the default mode network) that remained connected to subcortical brain structures. Propofol-induced unconsciousness is thus characterized by an initial, transitory dissociated synchronization at the largest scale of brain activity. Such cortico-subcortical decoupling and subsequent recoupling may allow the brain to detach from waking activity and reorganize into a functionally distinct state., (© Sleep Research Society 2020. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.)

Objectives: Electroconvulsive therapy (ECT) is one of the main techniques available for the treatment of such serious mental illnesses as schizophrenia and drug-resistant depression. The pre-anaesthetic assessment appropriate for patients with various mental disorders or pathologies does not differ substantially from that of any patient prior to undergoing anaesthesia for a surgical procedure. The present review aims to propose guidelines to achieve a higher level of safety and effectiveness during ECT in the most frequent situations, in accordance with the current literature., Methods: We conducted a search on the role of anaesthesia in ECT in the Ovid MEDLINE, PubMed, and SciELO (Scientific Electronic Library Online) databases, with special attention to the populations undergoing this type of therapy. The search was carried out between 1978 and December 2016., Results: We included the 96 articles that contained the most important recommendations for the preparation of this guide., Conclusions: We propose these guidelines in order to achieve a higher level of safety and effectiveness during ECT in special conditions. We also summarize the most important attitude to be taken into account by the anaesthesiologist in these cases., (Copyright © 2018 SEP y SEPB. Publicado por Elsevier España, S.L.U. All rights reserved.)

We present the case of an adult patient with drug-resistant epilepsy caused by extensive inflammation in the right cerebral hemisphere. She was scheduled to undergo right functional hemispherectomy, which is common in pediatric surgery, but about which few studies have been published with respect to adult patients. During the intraoperative period, the density spectral array of the bilateral bispectral index (BIS) VISTA TM monitoring system was used. We observed a power increase in low frequency (0.1-4Hz) and alpha bands (8-12Hz) in the right hemisphere, where the epileptogenic focus was. During disconnection from the frontal lobe, there was a marked decrease of power in low frequency and alpha bands on the right side, with no changes during disconnection from other areas of the brain. We think that further studies are needed to determine whether the density spectral array can be a useful tool for monitoring the effectiveness of functional hemispherectomy., (Copyright © 2018 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.)

Epilepsy surgery is a well-established treatment for patients with drug-resistant epilepsy. The success of surgery depends on precise presurgical localisation of the epileptogenic zone. There are different techniques to determine its location and extension. Despite the improvements in non-invasive diagnostic tests, in patients for whom these tests are inconclusive, invasive techniques such intraoperative electrocorticography will be needed. Intraoperative electrocorticography is used to guide surgical resection of the epileptogenic lesion and to verify that the resection has been completed. However, it can be affected by some of the anaesthetic drugs used by the anaesthesiologist. Our objective with this case is to review which drugs can be used in epilepsy surgery with intraoperative electrocorticography., (Copyright © 2017 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.)

We report the case of an aborted awake craniotomy for a left frontotemporoinsular glioma due to ammonia encephalopathy on a patient taking Levetiracetam, valproic acid and clobazam. This awake mapping surgery was scheduled as a second-stage procedure following partial resection eight days earlier under general anesthesia. We planned to perform the surgery with local anesthesia and sedation with remifentanil and propofol. After removal of the bone flap all sedation was stopped and we noticed slow mentation and excessive drowsiness prompting us to stop and control the airway and proceed with general anesthesia. There were no post-operative complications but the patient continued to exhibit bradypsychia and hand tremor. His ammonia level was found to be elevated and was treated with an infusion of l-carnitine after discontinuation of the valproic acid with vast improvement. Ammonia encephalopathy should be considered in patients treated with valproic acid and mental status changes who require an awake craniotomy with patient collaboration., (Copyright © 2014 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.)

Background and Objective: Neuromuscular blockers (NMBs) have traditionally been thought to increase the risk of respiratory complications, although drawing conclusions in this respect would require complex studies in large patient samples. The aim of this study was to analyze data from the ARISCAT study to obtain an overall picture of how NMBs are being used and blocks are reversed in Catalonia, Spain., Material and Methods: NMB use as reflected in data from the ARISCAT study was analyzed. Case information from the database was organized into 4 groups: for patients not receiving a NMB (No-NMB), patients whose NMB block was performed with succinylcholine alone (SC), patients who received a single dose of a nondepolarizing NMB (SD-NMB), and patients who received additional doses of a nondepolarizing NMB or a continuous perfusion (AD-NMB). We analyzed patient characteristics, clinical and surgical characteristics, and complications during and after surgery in each of the groups. Variables were also analyzed according to whether the NMB effect had to be reversed., Results: Of the 2991 patients included in the ARISCAT study, 1545 received general or combined anesthesia. Of the 1545 patients, 1267 (89%) received a NMB and the block was reversed with an anticholinesterase agent in 54%. The group distribution was as follows: No-NMB, 103 patients; SC, 31; SD-NMB, 527; and AD-NMB, 709. The highest rate of comorbidity, longest duration of surgery, highest rate of complications during and after surgery, and the longest hospital stays were observed in the last of the 4 groups (AD-NMB). Reversion was required significantly more often after cardiothoracic and upper abdominal surgical procedures; the complication rates after those 2 types of surgery were statistically similar., Conclusions: Nondepolarizing NMBs are used in combination with general anesthesia often in Catalonia; their use is associated with duration and type of surgery. A reversal drug is administered relatively more often in Catalonia than in other geographic areas.