Bilateral Bispectral Index Monitoring Performance in the Detection of Seizures in Nonanesthetized Epileptic Patients: An Observational Study.

BACKGROUND: The aim of this observational study was to determine whether bilateral bispectral index (BIS) monitoring can detect seizures in epileptic patients. METHODS: Four-channel frontal BIS monitoring and standard 40-channel electroencephalography monitoring were conducted in epileptic patients undergoing evaluation for epilepsy surgery. The BIS numerical value, signal quality index, electromyography, suppression ratio, and color density spectral array were continuously recorded. In patients with electroencephalography-confirmed seizures, the mean value and trend (slope of linear regression) of bilateral BIS monitor parameters were analyzed from 1 minute before to 1 minute after seizure onset. RESULTS: Of 48 patients included in the study, 21 (43.8%) had at least 1 seizure. BIS numerical value was not able to detect focal or focal to bilateral tonic-clonic seizures. Considering all seizures, the only significant differences between recordings 1 minute before and 1 minute after seizure onset were a decrease in the signal quality index slope from 1 hemisphere (0.039±0.297 vs. -0.085±0.321, respectively; P =0.029) and in the mean signal quality index recorded from both hemispheres (left hemisphere: 65.775±30.599 vs. 61.032±26.285; P =0.016 and right hemisphere: 63.244±31.985 vs. 59.837±27.360; 0.029); these differences were not maintained after Hochberg adjustment for multiple comparisons. In seizures occurring during sleep, there was a change in the electromyography slope of 1 hemisphere before and after seizure onset (-0.141±0.176 vs. 0.162±0.140, respectively; P =0.038). There were variable responses in BIS parameters in the 3 patients who developed focal nonconvulsive seizure clusters. CONCLUSION: Bilateral BIS monitoring was not able to detect the occurrence of seizures in epileptic patients.

Eficacia diagnóstica y manejo posoperatorio de los pacientes sometidos a biopsia cerebral en un hospital universitario / Diagnostic yield and postoperative management of patients submitted to brain biopsy in a university hospital

Objetivo: Determinar la eficacia diagnóstica y la incidencia de complicaciones perioperatorias en pacientes sometidos a biopsia cerebral cerrada o por craneotomía, y valorar la duración de la vigilancia intensiva, para el diagnóstico precoz y el manejo de las complicaciones posoperatorias. Material y método: Estudio observacional retrospectivo, incluyendo todos los pacientes sometidos a biopsia cerebral entre enero de 2006 y julio de 2012. Se recogieron los datos demográficos, enfermedad asociada, tipo de biopsia, datos relevantes del intraoperatorio, el resultado de la anatomía patológica, la realización de prueba de imagen cerebral y su resultado, y la presencia, tipo y momento de aparición de las complicaciones posoperatorias. Resultados: Se analizaron un total de 76 biopsias (51 «cerradas», 25 «abiertas») en 75 pacientes. La efectividad diagnóstica fue del 98% en las «cerradas» y del 96% en las «abiertas». La mortalidad relacionada con el procedimiento fue de 3,9 y 4%, respectivamente. La incidencia de complicaciones mayores fue del 3,9% en biopsias «cerradas» y del 8% en biopsias «abiertas», apareciendo la mitad de ellas dentro de las primeras 24 h del posoperatorio, durante el ingreso en la Unidad de Cuidados Intensivos. La edad fue el único factor de riesgo para la aparición de complicaciones (p = 0,04). No encontramos diferencias de morbimortalidad entre los 2 grupos analizados. Conclusiones: La eficacia diagnóstica de nuestra serie ha sido muy alta. Dada la importancia del diagnóstico precoz de las complicaciones, recomendamos una vigilancia monitorizada en las primeras 24 h tras la realización de una biopsia cerebral tanto «abierta» como «cerrada»

Objective: To assess the diagnostic yield and the incidence of perioperative complications in patients undergoing an open or closed cerebral biopsy and to determine the length of intensive care monitoring, for early diagnosis and fast management of perioperative complications. Material and method: This was a retrospective analysis of all the patients that underwent brain biopsy between January 2006 and July 2012. We recorded demographic data, comorbidities, modality of biopsy, intraoperative clinical data, histological results, computed tomography scanning findings and occurrence, and type of perioperative complications and moment of appearance. Results: Seventy-six brain biopsies in 75 consecutive patients (51 closed and 25 open) were analysed. Diagnostic yield was 98% for closed biopsies and 96% for open biopsies. Mortality related to the procedures was 3.9 and 4%, respectively. The incidence of major complications was 3.9% for closed biopsies and 8% for open biopsies; half of these appeared within the first 24 postoperative hours, during patient stay in the Intensive Care Unit. Age was the only risk factor for complications (P = .04) in our study. No differences in morbimortality were found between the studied groups. Conclusions: Diagnostic yield was very high in our series. Because the importance of early diagnosis of complications for preventing long-term sequelae, we recommend overnight hospital stay for observation after open or closed brain biopsy

ProSeal Laryngeal Mask Airway Attenuates Systemic and Cerebral Hemodynamic Response During Awakening of Neurosurgical Patients: A Randomized Clinical Trial.

BACKGROUND: Extubation and emergence from anesthesia may lead to systemic and cerebral hemodynamic changes that endanger neurosurgical patients. We aimed to compare systemic and cerebral hemodynamic variables and cough incidence in neurosurgery patients emerging from general anesthesia with the standard procedure (endotracheal tube [ETT] extubation) or after replacement of the ETT with a laryngeal mask airway (LMA). MATERIALS AND METHODS: Forty-two patients undergoing supratentorial craniotomy under general anesthesia were included in a randomized open-label parallel trial. Patients were randomized (sealed envelopes labeled with software-generated randomized numbers) to awaken with the ETT in place or after its replacement with a ProSeal LMA. We recorded mean arterial pressure as the primary endpoint and heart rate, middle cerebral artery flow velocity, regional cerebral oxygen saturation, norepinephrine plasma concentrations, and coughing. RESULTS: No differences were found between groups at baseline. All hemodynamic variables increased significantly from baseline in both groups during emergence. The ETT group had significantly higher mean arterial pressure (11.9 mm Hg; 95% confidence interval [CI], 2.1-21.8 mm Hg) (P=0.017), heart rate (7.2 beats/min; 95% CI, 0.7-13.7 beats/min) (P=0.03), and rate-pressure product (1045.4; 95% CI, 440.8-1650) (P=0.001). Antihypertensive medication was administered to more ETT-group patients than LMA-group patients (9 [42.9%] vs. 3 [14.3%] patients, respectively; P=0.04). The percent increase in regional cerebral oxygen saturation was greater in the ETT group by 26.1% (95% CI, 9.1%-43.2%) (P=0.002), but no between-group differences were found in MCA flow velocity. Norepinephrine plasma concentrations rose in both groups between baseline and the end of emergence: LMA: from 87.5±7.1 to 125.6±17.3 pg/mL; and ETT: from 118.1±14.1 to 158.1±24.7 pg/mL (P=0.007). The differences between groups were not significant. The incidence of cough was higher in the ETT group (87.5%) than in the LMA group (9.5%) (P<0.001). CONCLUSIONS: Replacing the ETT with the LMA before neurosurgical patients emerge from anesthesia results in a more favorable hemodynamic profile, less cerebral hyperemia, and a lower incidence of cough.

[Diagnostic yield and postoperative management of patients submitted to brain biopsy in a university hospital]. / Eficacia diagnóstica y manejo posoperatorio de los pacientes sometidos a biopsia cerebral en un hospital universitario.

OBJECTIVE: To assess the diagnostic yield and the incidence of perioperative complications in patients undergoing an open or closed cerebral biopsy and to determine the length of intensive care monitoring, for early diagnosis and fast management of perioperative complications. MATERIAL AND METHOD: This was a retrospective analysis of all the patients that underwent brain biopsy between January 2006 and July 2012. We recorded demographic data, comorbidities, modality of biopsy, intraoperative clinical data, histological results, computed tomography scanning findings and occurrence, and type of perioperative complications and moment of appearance. RESULTS: Seventy-six brain biopsies in 75 consecutive patients (51 closed and 25 open) were analysed. Diagnostic yield was 98% for closed biopsies and 96% for open biopsies. Mortality related to the procedures was 3.9 and 4%, respectively. The incidence of major complications was 3.9% for closed biopsies and 8% for open biopsies; half of these appeared within the first 24 postoperative hours, during patient stay in the Intensive Care Unit. Age was the only risk factor for complications (P=.04) in our study. No differences in morbimortality were found between the studied groups. CONCLUSIONS: Diagnostic yield was very high in our series. Because the importance of early diagnosis of complications for preventing long-term sequelae, we recommend overnight hospital stay for observation after open or closed brain biopsy.

Detección de embolismo aéreo venoso y de foramen oval permeable en pacientes neuroquirúrgicos intervenidos en posición de sedestación / Detection of venous air embolism and patent foramen ovale in neurosurgery patients in sitting position

INTRODUCCIÓN: La detección precoz del embolismo aéreo venoso (EAV) durante las intervenciones neuroquirúrgicas en sedestación disminuye la gravedad de sus complicaciones. OBJETIVOS: Analizar la detección de EAV y sus repercusiones en pacientes intervenidos en sedestación. Comprobar la frecuencia de aspiración de aire a través de una vía venosa central. Valorar la viabilidad del uso del Doppler transcraneal (DTC) en quirófano para el diagnóstico del foramen oval permeable (FOP). MATERIAL Y MÉTODOS: Estudio prospectivo de intervenciones neuroquirúrgicas consecutivas realizadas durante 5 años en sedestación. Como método diagnóstico del EAV se empleó el Doppler precordial y el CO2 espirado. El FOP se exploró tras la inducción anestésica mediante DTC. RESULTADOS: Ciento treinta y seis pacientes fueron intervenidos en sedestación, 93 craneotomías y 43 cirugías de columna cervical. Veintidós pacientes (16,2%) fueron diagnosticados de EAV (21,5% de las craneotomías y 4,7% de las cirugías de columna; p = 0,013). En el 59% de los casos se aspiró aire a través del catéter venoso central. Hubo afectación hemodinámica en 3 pacientes, alteración de la oxigenación en 4 y neumoencéfalo clínicamente relevante en 5. Dos pacientes (1,4%) fueron diagnosticados de FOP, pero no presentaron episodios de EAV ni embolia aérea paradójica. CONCLUSIONES: Confirmamos una mayor incidencia de EAV en craneotomías que en cirugía de columna cervical en sedestación. Obtuvimos aire a través del catéter venoso central en más de la mitad de los casos. Con nuestra sistemática, ningún paciente presentó complicaciones críticas intraoperatorias. La baja incidencia de FOP detectada con DTC requerirá modificar nuestro protocolo realizado con el paciente anestesiado

INTRODUCTION: Early detection of venous air embolism (VAE) during neurosurgical procedures in sitting position decreases the severity of its complications. OBJECTIVES: our aim was to analyse the detection of VAE and its impact on patients operated in a sitting position, verify air aspiration through a central venous catheter and assess the feasibility of the routine use of transcranial Doppler (TCD) for intraoperative diagnosis of patent foramen ovale (PFO). MATERIAL AND METHODS: We performed a prospective study of consecutive neurosurgical procedures performed in the sitting position for 5 years. Precordial Doppler and end-tidal carbon dioxide were the diagnostic methods for VAE. PFO was explored by TCD after anaesthetic induction. RESULTS: 136 patients were operated in the sitting position, 93 craniotomies and 43 cervical spine procedures. Twenty-two patients (16.2%) were diagnosed with VAE (21.5% of craniotomies and 4.7% of spinal surgeries; p = .013). In 59% of cases, air was aspirated through the central venous catheter. There was haemodynamic involvement in 3 patients, impaired oxygenation in 4 and clinically relevant pneumocephalus in 5 of them. Two patients (1.4%) were diagnosed with PFO, but did not present episodes of VAE or paradoxical air embolism. CONCLUSIONS: The series analysed confirmed a higher incidence of VAE in craniotomies than in cervical spine surgery in a sitting position. We were able to aspirate air through the central venous catheter in more than half the cases. No patients suffered critical intraoperative complications following our approach. The low incidence of PFO detected with TCD will imply a modification of our protocol performed on anaesthetised patients

[Detection of venous air embolism and patent foramen ovale in neurosurgery patients in sitting position]. / Detección de embolismo aéreo venoso y de foramen oval permeable en pacientes neuroquirúrgicos intervenidos en posición de sedestación.

INTRODUCTION: Early detection of venous air embolism (VAE) during neurosurgical procedures in sitting position decreases the severity of its complications. OBJECTIVES: our aim was to analyse the detection of VAE and its impact on patients operated in a sitting position, verify air aspiration through a central venous catheter and assess the feasibility of the routine use of transcranial Doppler (TCD) for intraoperative diagnosis of patent foramen ovale (PFO). MATERIAL AND METHODS: We performed a prospective study of consecutive neurosurgical procedures performed in the sitting position for 5 years. Precordial Doppler and end-tidal carbon dioxide were the diagnostic methods for VAE. PFO was explored by TCD after anaesthetic induction. RESULTS: 136 patients were operated in the sitting position, 93 craniotomies and 43 cervical spine procedures. Twenty-two patients (16.2%) were diagnosed with VAE (21.5% of craniotomies and 4.7% of spinal surgeries; p=.013). In 59% of cases, air was aspirated through the central venous catheter. There was haemodynamic involvement in 3 patients, impaired oxygenation in 4 and clinically relevant pneumocephalus in 5 of them. Two patients (1.4%) were diagnosed with PFO, but did not present episodes of VAE or paradoxical air embolism. CONCLUSIONS: The series analysed confirmed a higher incidence of VAE in craniotomies than in cervical spine surgery in a sitting position. We were able to aspirate air through the central venous catheter in more than half the cases. No patients suffered critical intraoperative complications following our approach. The low incidence of PFO detected with TCD will imply a modification of our protocol performed on anaesthetised patients.