Valved underwater drainage apparatus

Abstract

A drainage apparatus for evacuating fluids from cavities including a collection chamber for collecting fluids from the body cavity, a water seal chamber and a pressure regulator chamber. A valve mechanism is provided in the water seal chamber to permit the outflow of gases from the apparatus in the event of a sudden increase in pressure in the device due to respiratory movements or leakage of air.

We claim: 
     
       1. In an underwater drainage device for draining fluid from a pleural cavity comprising a collection chamber having an inlet, a thoracotomy tube interconnecting the pleural cavity and the inlet to said collection chamber whereby the collection chamber receives and collects fluids drained from the pleural cavity, an outlet from the collection chamber, a U-shaped water seal chamber, a U-shaped manometer chamber, the upper end of one arm of the U-shaped water seal chamber being connected to the outlet from the collection chamber, the upper end of the other arm of the U-shaped water seal chamber being connected to the upper end of one arm of the U-shaped manometer chamber, the other arm of the U-shaped manometer chamber being open to atmosphere, a connection from said device with a source of suction, during normal operation the source of suction maintaining the pleural cavity at a negative pressure determined by the fluid in the manometer chamber, and .Iadd.check .Iaddend.valve means .Iadd.disposed .Iaddend.in said device .Iadd.between the water seal of the water seal chamber and the lower part of the U-shaped manometer chamber on the normally lower pressure side thereof, .Iaddend.said .Iadd.check .Iaddend.valve means being normally closed and opening only during sudden abnormal conditions when the pressure within the pleural cavity exceeds atmospheric pressure, said valve means being an outlet to atmosphere in addition to the outlet to atmosphere provided by the arm of the U-shaped manometer chamber open to atmosphere, said valve means being positioned in said device to vent to atmosphere sudden positive pressure surges within the pleural cavity occurring even during normal operation of the suction source and to prevent said sudden positive pressure surges from causing fluid within the U-shaped manometer chamber from passing out through the arm open to atmosphere to vary the degree of vacuum imposed by the source of suction. 
     
     
       2. In an underwater drainage device according to claim 1 wherein said .Iadd.check .Iaddend.valve means is disposed in said device on the low pressure side of the U-shaped manometer chamber. 
     
     
       3. In an underwater drainage device according to claim 1 wherein said .Iadd.check .Iaddend.valve comprises an opening to atmosphere in a wall of said device and means covering said .[.openings.]. .Iadd.opening .Iaddend.to atmosphere when the pressure within said device is less than atmosphere. .Iadd. 4. In an underwater drainage device according to claim 1 wherein said check valve means comprising a mechanical seating member and a mechanical valve member engagable with said seating member such that when said valve member engages said seating member, said valve is closed and when said valve member does not engage said seating member said valve is open. .Iaddend.