A trocar assembly for providing a pressurized insufflation fluid into a patient cavity and for providing sealable access to the patient cavity by a surgical instrument. The assembly comprises an inner tubular member having a proximal end and a distal end. An outer tubular member is disposed about the...http://www.google.es/patents/US7182752?utm_source=gb-gplus-sharePatente US7182752 - Continuous gas flow trocar assembly
