Control of intraoperative bleeding with hydrostatic pressure during endoscopic surgery.

Though intracranial endoscopic surgery has several advantages, poor visibility caused by bleeding from the operative field is one of its limitations. In two cases involving endoscopic III ventriculostomy the authors encountered moderate bleeding, and this was controlled with 'water column tamponade.' Following the application of hydrostatic pressure of 40-50 cmH2O for less than 2 min, the bleeding temporarily stopped and the operative field became clear. Several applications of this tamponade made it possible to complete the procedures. Although the pressure applied by the water column was not high enough to disturb the cerebrovascular autoregulation, blood pressure rose significantly during application of the water column tamponade. This method was valuable for the completion of procedures when bleeding was not at high pressure from large arteries. Careful monitoring of the blood pressure is mandatory, and adjustment of the pressure applied will make the procedure safer.