In Reply:-As Drs. Robinson and Gozal stated, we did detect a variance in the manufacturing process as related to the assembly of certain watertraps. This intermittent defect was reported by Dr. Robinson and some other users of this product. On return of the suspect traps and careful examination and testing by Criticare and our production house, we changed the manufacturing process to eliminate the potential for this phenomenon to occur.

In the case of Dr. Robinson and all other customers who noticed this problem, we replaced all of their existing stock of traps with new production units. To date, we believe that all questionable traps have been replaced with new production units. This problem was very intermittent and extremely difficult to identify to any specific lot of traps.

Because of acute observation by Dr. Robinson, his staff, and others who were extremely helpful in bringing this issue to our attention, we were able to affect changes to address this problem. We welcome and encourage critical review and assessment of our monitoring systems by the clinical users like Steve and his staff. Only through this dialog can we, as a manufacturer, produce products that meet the clinical needs in safety and usability for vital monitoring products.

Daryl Lehman

Marketing Product Manage-Gas Analysis Systems; Criticare Systems Inc.; P.O. Box 26556; Milwaukee, Wisconsin 53226

(Accepted for publication April 24, 1997.)