SUPERIMPOSED INSPIRATORY WORK OF THE SIEMENS-SERVO-300 VENTILATOR DURING CONTINUOUS POSITIVE AIRWAY PRESSURE

Objective: To compare the superimposed inspired work of breathing (SIW ) of the Siemens Servo 300 ventilator with the Siemens Servo 900C vent ilator. Design: Comparisons made at continuous positive airway pressur e (CPAP) levels of 0, 4, and 8 cmH(2)O, and at trigger sensitivities o f -1 and -2 cmH(2)O, and flow triggering. Setting: General intensive c are unit in a University teaching hospital. Patients: 7 patients recei ving CPAP. Results: At all levels of CPAP, the SIW was significantly l ess with the Siemens Servo 300 ventilator as compared to the Siemens S ervo 900C ventilator despite similar trigger sensitivities. No signifi cant difference was found in the SIW of the Servo 300 ventilator when comparing trigger sensitivities of -1 cmH(2)O, -2 cmH(2)O, and flow tr iggering. Different levels of CPAP had no effect on SIW. Conclusions: The Siemens Servo 300 ventilator entails less superimposed inspiratory work of breathing than the Siemens Servo 900C ventilator.