ECMO venovenoso durante procedimiento endoscópico de permeabilización de la vía aérea central en pacientes con riesgo vital: reporte de 2 casos / Use of venovenous extracorporeal membrane oxygenation (ECMO) during endoscopic treatment of central airway obstruction and vital risk: report of 2 cases

Resumen: La oxigenación por membrana extracorpórea (ECMO) es de gran utilidad al proveer soporte ventilatorio a pacientes con hipoxia, pero su utilidad en el manejo de pacientes con obstrucción central de la vía aérea y riesgo vital no ha sido frecuentemente usada. La broncoscopía intervencional como terapia bajo ventilación convencional es de alto riesgo en este tipo de pacientes, pero es posible lograr excelentes resultados al ser asociada a ECMO. Comunicamos el caso clínico de 2 pacientes que presentaban disnea en reposo y falla ven1ila1oria aguda ca1as1rófica debido a una obstrucción casi total del lumen traqueal, de causa tumoral. En ambos pacientes en forma urgente se inició soporte circulatorio mediante ECMO VV, mientras se efectuaba la resección tumoral broncoscópica. Luego de terminada la cirugía traqueal, en ambos pacientes se retiró el soporte, siendo decanulados sin eventos y con una buena evolución clínica posterior. Se discute el beneficio del soporte ECMO en este tipo de pacientes.

Abstract: In patients with severe central airway stenosis bronchoscopy-guided intervention therapy under conventional ventilation conveys a high risk. Extracorporeal membrane oxygenation (ECMO) provides very good cardiopulmonary support, but is rarely used in bronchoscopy-guided interventional therapy. We report 2 patients with resting dyspnea due to severe tumor tracheal obstruction and acute pulmonary failure with imminent vital risk. Both patients were cannulated and the ECMO circuit installed on a nearly emergency basis. Tumors were excised, and the patients weaned from cardiopulmonary bypass uneventfully. Subsequent clinical course was satisfactory in both cases. A brief discussion of this condition is included.

Anethole isomerization and dimerization induced by acid sites or UV irradiation.

The formation of cis-anethole and various dimers as a result of the exposure of trans-anethole to microporous solid acids (dealuminated HY zeolites), or UV-Vis irradiation was established by means of high resolution gas chromatography coupled to mass spectrometry. 3,4-bis-(4-Methoxyphenyl)-(E)-hex-2-ene was the most abundant compound among eight different methoxyphenyl-disubstituted hexenes produced by electrophilic addition and elimination reactions induced by HY zeolites. (1a,2a,3b,4b)-1,2-bis(4-Methoxyphenyl)-3,4-dimethylcyclobutane was the principal component in the mixture of 5 methoxyphenyl-disubstituted cyclobutanes found, together with cis-anethole, after UV-Vis irradiation of a trans-anethole solution in toluene.