Abstract: An apparatus for inserting a thoracotomy tube in a patient without damaging adjacent lung tissues is provided. The thoracotomy tube is adapted to receive a trocar having screw threads on the distal end thereof. The proximal end of the trocar has a handle thereon to rotate the trocar so that the screw threaded distal end forms an incision within the skin of the patient and the tip end of the screw thread passes into the pleural cavity. The distal end of the thoracotomy tube is provided with screw threads on the outer surface thereof to form a continuation of the screw threads of the trocar. The distal tip or end of the trocar terminates in a short flexible tube. A hollow needle extends through a central passageway in the trocar and through the flexible tip on the trocar. The opposite end of the hollow needle is provided with a pressure chamber which is in fluid communication with the passageway in the needle.

Abstract: A method and apparatus for induction of pneumoperitoneum and insertion of a laparoscopic sheath is provided in which a trocar carrying a sheath or cannula has a tapered distal end with screw threads formed on the outer surface of the distal end. The distal tip or end terminates in a short flexible tube. A hollow needle extends through a central passageway in the trocar and through the flexible tip on the trocar. The opposite end of the hollow needle is provided with a pressure chamber which is in fluid communication with the passageway in the needle. In use, the trocar and cannula are screwed into the body tissues of the patient and when the distal end of the needle enters the peritoneal space within the body, liquid within the pressure chamber passes through the hollow needle and into the peritoneal space. The release of the fluid from the pressure chamber is an indicator to the surgeon that the end portion of the needle has entered the peritoneal space.