In Reply:—

The authors report that they connected a 19-mm hose to a 22-mm scavenger needle valve. A 19 mm—22 mm difference is the current standard for differentiating breathing circuit connections. In fact the needle valve is 7/8 inch, which is slightly larger than 22 mm. It is possible to overcome the intended incompatibility of 19 mm and 22 mm components if excessive force is used. The physical effort to make the misconnection described by the authors had to be as great or greater than connecting a 19-mm hose to a 22-mm connector, and we believe, should have drawn attention to the error. Extreme care must be used any time it becomes necessary to separate and reconnect any components of the breathing circuit while a patient is connected to the circuit.

The authors correctly report that the design of the scavenger needle valve was changed from a screw type to a wing nut type in 1982. However, Narkomed 2B anesthesia machines were first sold in mid 1987. Thus, relating this event to a Narkomed 2B is misleading. It is likely that an old absorber assembly which contained the screw type needle valve was attached to the Narkomed 2B some time after the Narkomed 2B was shipped from the factory.

For clarification, the list price for the needle valve components is $100.00; however, prices are subject to change. Labor and travel would be extra if the customer wants the valve components installed by Draeger Medical, Inc.

The authors state that using the screw type needle valve is still “approved by North American Drager.” It is ambiguous what the authors mean by that statement. The screw type scavenger needle valve has not been used in the manufacture of North American Drager (Draeger Medical, Inc.) anesthesia machines since the design changed in 1982. The decision to use or not use medical devices of any type rests with the health care professional, not with the manufacturer.