El efecto del flumazenil sobre la recuperación de anestesia general con isoflurano: una prueba aleatoria controlada / Effect of flumazenil on recovery from general anesthesia with isoflurane: A randomized controlled trial

Background and objectives: The inhalational anesthetic isoflurane is widely used in general anesthetics. Its mechanism of action involves interaction with the receptor of gamma-aminobutyric acid (GABA), which is also the binding site for benzodiazepines. Flumazenil, benzodiazepine antagonist, reverses the effects of these drugs in GABA receptors and could therefore also reverse the effect of isoflurane. In anesthesia practice, extubation and early anesthetic recovery reduce morbidity and incidence of complications. The objective of this trial is to determine whether the use of lumazenil may contribute to faster recovery from anesthesia. Methods: Forty patients scheduled to undergo general anesthesia with isolurane were enrolled in this prospective, double-blind, randomized trial. Patients were randomized to receive, at the end of anesthesia, lumazenil or placebo as allocated into two groups. The anesthetic technique was standardized. The groups were compared concerning values of cerebral state index (CSI), heart rate, blood pressure and oxygen saturation from the application of flumazenil or placebo until 30 min after injection. Data regarding time to extubation, time to reach 10 points in the Aldrete-Kroulic score (AK = 10) and Vigilance score (VS = 10) was also collected. ANOVA test was applied to analyze the results, considering p < 0.05. Results:Patients receiving flumazenil achieved faster extubation than the control (p = 0.033). No differences were observed in values of CSI, the time until AK = 10 and until VS = 10. Conclusions: Administration of lumazenil at the end of isolurane general anesthesia resulted in earlier extubation in studied patients.

Introducción y objetivos: El isoflurano es un anestésico inhalatorio ampliamente utilizado en anestesia general. Su mecanismo de acción involucra el receptor del ácido gamma-aminobutírico. Dicho receptor es también el sitio de acción de las benzodiazepinas. El flumazenil, antagonista benzodiazepínico, podría revertir los efectos del isoflurano. En la práctica, la extubación y recuperación anestésica tempranas reducen la morbilidad e incidencia de complicaciones. El objetivo del estudio es determinar la contribución del uso del flumazenil en la recuperación anestésica. Métodos: Se realizó un estudio doble ciego, prospectivo, aleatorio de 40 pacientes bajo anestesia general con isoflurano que recibieron flumazenil o placebo según aleatorización previa. La técnica anestésica fue estandarizada. Los parámetros comparados en los 2 grupos fueron frecuencia cardiaca, tensión arterial, saturación de oxígeno y niveles del Índice Biespectral, desde la aplicación del flumazenil y durante los 30 minutos posteriores. El tiempo transcurrido entre la inyección del medicamento y la extubación, así como el tiempo requerido para alcanzar 10 puntos en la Escala de Aldrete-Kroulic y la Escala de Vigilancia, también fueron contabilizados. El análisis de la varianza fue aplicado para comparar los datos, considerando p<0.05. Resultados: Los pacientes que recibieron flumazenil fueron extubados en menor tiempo que los del grupo placebo (P = 0.033). No se observaron diferencias entre los valores del Índice Biespectral y el tiempo necesario para alcanzar 10 puntos en la Escala de Aldrete-Kroulic y la Escala de Vigilancia. Conclusiones: La administración de flumazenil al final de la anestesia general con isoflurano disminuyó el tiempo a la extubación.

Vertebral fracture assessment by dual X-ray absorptiometry: a valid tool to detect vertebral fractures in community-dwelling older adults in a population-based survey.

OBJECTIVE: Vertebral fractures are associated with higher morbidity and mortality. Since 70% of vertebral fractures are clinically silent, a radiologic image of the spine has to be acquired for the diagnosis. The aim of this study was to compare the performance of Vertebral Fracture Assessment (VFA) by dual x-ray absorptiometry (DXA) with radiographs to identify vertebral fractures in community-dwelling older adults. METHODS: A total of 429 older adults (ages ≥65 years) were enrolled in this cohort. VFA by DXA measurements were evaluated by 2 expert rheumatologists by consensus, and spine radiographs were analyzed according to the semiquantitative method by an expert radiologist. The correlation between VFA and spine radiographs to identify vertebral fractures was analyzed by kappa scores. RESULTS: The prevalence of vertebral fractures in VFA and radiographs was 29.1% and 29.4%, respectively (P = 0.99). The frequency of unavailable vertebrae was significantly lower in spinal radiographs than in VFA (0.9% and 5.6%, respectively; P < 0.001), particularly in T4-T6. According to VFA, 5,013 vertebrae (96%) were identified as normal and 144 (2.7%) had grade 1, 58 (1.1%) had grade 2, and 12 (0.2%) had grade 3 fractures. The sensitivity of VFA was 72.9% and the specificity was 99.1% to identify vertebral fractures. The sensitivity increased to 92% and the specificity increased to 99.9% when excluding grade 1 deformities. A good correlation between VFA and radiographs (κ = 0.74) was observed, and the exclusion of grade 1 resulted in even better agreement (κ = 0.84). CONCLUSION: In community-dwelling older adults, VFA and radiographs had comparable performances in identifying vertebral fractures, particularly if mild deformities are excluded. Therefore, this methodology is a feasible and promising alternative to improve the management of patients with a high risk of osteoporotic fractures.