The maintenance records covering a 12-month period for 16 Puritan-Bennett MA-1, 7 Bourns BEAR-1, and 3 Siemens-Elema Servo #900-B volume ventilators were compared. The MA-1s had an average of 15,555 hours use prior to the study, compared with 200 average hours on each BEAR and 2,600 on each Servo ventilator. The MA-1s required the least number of repairs and operated longest between repairs, with 18,999 average hours of use per repair, compared with 4,955 hours for the BEAR-1 and 599 hours for the Servo ventilator. The average time required for repair was highest for the MA-1. Most repairs to the BEAR-1 were compressor-related and most were performed in the hospital, as were the repairs to the Servo ventilators. All MA-1 repairs were performed at Puritan-Bennett. The technical advantages of the BEAR-1 and Servo ventilators are convenient, but because of the frequency of repair of these units they are probably more suited to institutions where close supervision and technical backup are available.
