Medical fluid drainage and sampling system

Claim 1

In a medical fluid drainage system for conducting fluid from the body of a patient, said drainage system comprising a fluid collection vessel and a fluid collection tube, the tube being connected at one end to a catheter insertable in the patient and to the vessel at another end, the improvement comprising, a wall defining a closed unitary sample chamber mounted intermediately in said collection tube between the catheter and the collection vessel, establishing an input section of the tube between the catheter and the sample chamber, the input section being connecteD to a first opening in the wall and the sample chamber also establishing an output section of the tube between the collection vessel and the sample chamber, the output section being connected to an output tubular stem means extending through a second opening in the wall for collecting a sample in the chamber and terminating inside said chamber and spaced from said wall at its termination within the chamber, an elastomeric self-sealing seal means in the wall of said chamber constructed and located to receive a sterile hypodermic needle therethrough into communication with a collected sample and to maintain its seal upon withdrawal of such hypodermic needle whereby collection of the most recently drained fluid from a patient''s body is permitted by sterile invasion of the system.