[Anesthesia in 2 cases of resection of a renal tumor involving the vena cava]. / Anestesia en dos casos de resección de un tumor renal con extensión a la vena cava.

Renal tumors can be associated with a thrombus that affects the renal vein and even the inferior vena cava. Radical surgery may require a 2-phase approach involving different anesthetic techniques: an abdominal approach for removal of the kidney and a thoracic approach for extraction of the thrombus, with extracorporeal circulation and in some cases cessation of blood circulation. We present 2 cases in which nephrectomy and thrombectomy were carried out with the support of extracorporeal circulation. The thrombus was in the renal vein and the inferior vena cava, extending to the outlet to the right atrium in both cases. In 1 case a portion reached the bifurcation of the pulmonary artery. The operation was performed under hypothermia to reduce circulation and did not require aortic clamping, cardioplegia, or cessation of blood flow.

[Comparison of the bispectral index and spectral entropy in gynecological surgery]. / Estudio comparativo del indice biespectral y la entropía espectral en cirugía ginecológica.

OBJECTIVES: Spectral entropy quantifies variations in cortical electrical activity measured by electroencephalography and frontal activity measured by electromyography. The aim of this study, in the context of general anesthesia, was to compare bispectral index values with the two components of spectral entropy: state entropy and response entropy. MATERIAL AND METHODS: Sixteen women (ASA I-II) undergoing gynecological surgery were enrolled. The bispectral index was maintained between 40 and 50 for all patients. Both sensors, for monitoring the bispectral index and spectral entropy, were placed on each patient. Simultaneous readings were recorded at the following moments: operating room arrival, induction, relaxation, intubation, switching on the vaporizer, start of surgery, traction of the intestinal mesenteries and maneuvering of the electric scalpel, switching off the vaporizer, end of surgery, during cough, extubation, and eye opening. The data sets were subjected to analysis of variance, and the intraclass correlation coefficient (ICC) was used to analyze agreement. RESULTS: Differences between mean values of the bispectral index, state entropy and response entropy were observed at operating room arrival, intubation, and induction. Differences when the patient awakened from anesthesia were observed only between the bispectral index and response entropy, on the one hand, and state entropy on the other. There was no agreement (ICC<0.7) upon operating room arrival, maneuvering the electric scalpel, or awakening from anesthesia. CONCLUSION: The bispectral index, state entropy, and response entropy show good agreement during recordings that reflect the effects of anesthesia. The differences observed at baseline and upon awakening can be attributed to frontal electromyographic activity. Distinguishing cortical electrical activity from frontal electromyographic activity may provide additional information in these situations.