Akademik Veri Yönetim Sistemi
JOURNAL OF INTERNATIONAL ADVANCED OTOLOGY, cilt.6, sa.3, ss.331-336, 2010 (SCI-Expanded)
Objectives: Controlled hypotension is commonly used to achieve a bloodless operative field which is needed for successful middle ear surgery. Dexmedetomidine can be a potential agent in controlled hypotension. In this study we investigated efficacy of dexmedetomidine as an adjunct to induce controlled hypotension in tympanoplasty with low-flow anesthesia. Materials and Methods: Forty patients undergoing middle ear surgery were studied. Anesthesia was induced with thiopental and vecuronium bromide. Maintenance of anesthesia was achieved by 1.5 % isoflurane delivered in mixture of O2 and N2O, 4.4 L.per minute for 10 min and then flow rate was reduced to 1 L.min-1 and isoflurane concentration increased 2 %. Group Dexmedetomidine (In Group D, n=20), Dexmedetomidine (0,1 mu g.kg-1.min-1 for 10 minutes) was administered before induction and continued with a rate between 0,2-0,7 mu g.kg-1.h-1 and Group Saline (Group S, n=20) received normal saline with a rate of 50 ml.h-1. Infusions were stopped with the end of microsurgery. Twenty minutes before the replacement of tympanic membrane greft, N2O was discontinued and then the patients were extubated. Hemodynamic parameters, quality of the surgical field and surgeon's satisfaction were evaluated. Results: Demographic and hemodynamic data, the quality of the surgical field and surgeon's satisfaction were similar in both groups. Desired level of hypotension was achieved at the 5 th minute in group D, but in group S it couldn't be achieved until the 30th minute. Conclusion: Dexmedetomidine was effective in inducing consistent and sustained controlled hypotension in low-flow anesthesia during middle ear microsurgery.