Agentes farmacológicos utilizados em anestesia geral com hipotensão induzida para realização de cirurgia ortognática : uma revisão sistemática

Abstract

Anesthesia with induced hypotension is a technique used in orthognathic surgery in order to reduce the amount of bleeding, to improve the visualization of the operative field and to shorten the surgical time. The objective of this work was to carry out a systematic review about the topic, raising information on the main pharmacological agents used as well as the results of their applications. We collected studies published until November 2017 in the electronic databases Medline, Cochrane, Embase, Web of Science, in gray literature and by manual search. Of a total of 44 articles, only 21 were selected according to the inclusion criteria. The most commonly used hypotensive agents were nitroglycerin followed by remifentanil and sodium nitroprusside. The mean bleeding time in hypotension was 784,62±383,67 mL (p≥0,944) whereas the mean surgical time was 298,26±76,22 minutes (p≤0,000), only the latter with statistical significance. The use of local anesthetics produces significant results in reducing bleeding. It was not possible to conclusively determine the best pharmacological protocol for induced hypotension due to lack of data. The hypotensive agents sevoflurane associated with remifentanil, esmolol, isoflurane and remifentanil and only remifentanil showed better results in the reduction of bleeding. In addition, only the drugs esmolol and dexmedetomidine has shown significant reduction in operative time. In general, although there was a reduction in the amount of blood lost and in the operative time, only the latter presented a statistical difference compared to the normotensive technique. It is possible to conclude that the application of local anesthetics combined with induced hypotension generates less intraoperative bleeding.