Patent ID: 9089351
Filing Date: 2015-07-28
Classification: A61B

Abstract:
1. A surgical apparatus, comprising: a shaft having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end, wherein a portion of the shaft including the distal end is configured to be inserted into an environment at a surgical insufflation gas pressure; an end effector coupled to the distal end of the shaft; an internal seal disposed within the lumen at a position along the portion of the shaft, wherein the internal seal fluidically separates a first portion of the lumen distal to the internal seal from a second portion of the lumen proximal to the internal seal, wherein the second portion of the lumen is at a pressure lower than the surgical insufflation gas pressure in an inserted position of the portion of the shaft into the environment; and a sheath disposed around an external surface of at least the portion of the shaft; wherein the sheath comprises a material that is permeable to gas; and wherein, in the inserted position of the portion of the shaft into the environment, the internal seal and the sheath are configured to equalize a pressure in the first portion of the lumen to approximately the surgical insufflation gas pressure.