Neonatal Invasive Pressure Support Ventilation: A Comparison of New Generation Adult ICU Ventilators

Abstract

Background: Essentially all new generation adult ICU ventilators are designed to provide ventilation of neonates to adults. Nihon Kohden recently introduced a new ventilator to the market the NKV 500. To determine the performance of this ventilator during neonatal pressure support it needs to be compared to established ICU ventilators. In this study we compared the gas delivery capabilities of the new Nihon Kohden 550 ventilator (NKV 550) to that of the Medtronic PB980 and the Drager V500 ventilators. We hypothesized that if these ventilators were optimally set in pressure support ventilation there would be no differences in trigger response, pressurization time and volume delivery. Methods: Evaluations were performed with the IngMar ASL 5000 computerized lung simulator using a dry circuit and the Fisher & Paykel RT260 neonatal ventilator circuit. The ASL 5000 was set to simulate neonatal lung mechanics with a weak, normal and strong ventilatory drive (P0.1 1, 4.2 and 7.3 cm H₂O) and inspiratory time varying from 250 to 400 milliseconds (ms). Evaluations were performed without a leak and with a leak (1 to 1.5 L/min). Ventilator trigger sensitivity, rise time and termination criteria were optimally set. Each ventilator was set to deliver 5/5, 10/5 and 15/10 cm H₂O pressure support above PEEP. A total of 18 trials were conducted on each ventilator. Each trial lasted 2 min. The last 10 breath of each trial were analyzed. Trigger time (TT, ms), max pressure to trigger (MaxTrigP, cm H₂O), time to max trigger pressure (T-Tpress, ms), trigger pressure time product (PTP, cm H₂O -ms), time to 90% of peak pressure (T90, ms), and tidal volume (V_T, mL) were compared among ventilators using ANOVA for repeated measures. Potentially important clinical differences were defined as a P < .001 and >10% difference among ventilators. Results: The only potentially clinically important difference identified among variables evaluated was maximum trigger pressure(see table). Even this difference, although it met our criteria (P < .001 and >10%), is small (-0.23 vs -0.28 cm H₂O across ventilators) and unlikely clinically important. Conclusions: The NKV500, PB980 and V500 all performed similarly during this evaluation. The only potentially important difference was maximum trigger pressure. Disclosures: Robert Kacmarek is a consultant for Medtronic’s and Orange Medical and has received research grants from Medtronic’s and Venner Medical. All other authors report no conflict of interest