Trocar with tissue penetration pressure indicator

摘要

The present invention relates to a trocar and method for penetrating body tissue. The trocar includes an obturator assembly and a cannula assembly. The obturator assembly has an obturator shaft with a distal end portion adapted to penetrate body tissue and at least one channel extending between a proximal end portion of the shaft and the distal end portion. A pressure indicating system is positioned at the proximal end of the shaft and is provided to respond to the passage of gases through the channel and provide a visual indication when the distal end has penetrated the body tissue. A safety system is associated with the obturator shaft and responsive to gas pressure to shield the distal end portion of the shaft after penetration of the body tissue.