RT Journal Article SR Electronic T1 Aspiration of Dead Space in the Management of Chronic Obstructive Pulmonary Disease Patients With Respiratory Failure JF Respiratory Care FD American Association for Respiratory Care SP 257 OP 262 VO 49 IS 3 A1 You-Ning Liu A1 Wei-Guo Zhao A1 Li-Xin Xie A1 De-Sen Cao A1 Liang-An Chen A1 Jian-Peng Zhang A1 Bo Zhang A1 Ying-Min Ma A1 Yu-Zhu Li A1 Xin-Gang Zhang A1 Yan-Hong Jia YR 2004 UL http://rc.rcjournal.com/content/49/3/257.abstract AB INTRODUCTION: Carbon dioxide clearance can be improved by reducing respiratory dead space or by increasing the clearance of carbon-dioxide-laden expiratory gas from the dead space. Aspiration of dead space (ASPIDS) improves carbon dioxide clearance by suctioning out (during expiration) the carbon-dioxide-rich expiratory gas while replacing the suctioned-out gas with oxgenated gas. We hypothesized that ASPIDS would allow lower tidal volume and thus reduce exposure to potentially injurious airway pressures. METHODS: With 8 hemodynamically stable, normothermic, ventilated patients suffering severe chronic obstructive pulmonary disease we tested the dead-space-clearance effects of ASPIDS. We compared ASPIDS to phasic tracheal gas insufflation (PTGI) during conventional mechanical ventilation and during permissive hypercapnia, which was induced by decreasing tidal volume by 30%. The mean PaCO2 reductions with PTGI flows of 4.0 and 6.0 L/min and during ASPIDS (at 4.0 L/min) were 32.7%, 51.8%, and 53.5%, respectively. Peak, plateau, and mean airway pressure during permissive hypercapnia were significantly lower than during conventional mechanical ventilation but PTGI increased peak, plateau, and mean airway pressure. However, pressures were decreased during permissive hypercapnia while applying ASPIDS. Intrinsic positive end-expiratory pressure also increased with PTGI, but ASPIDS had no obvious influence on intrinsic positive end-expiratory pressure. ASPIDS had no effect on cardiovascular status. CONCLUSIONS: ASPIDS is a simple adjunct to mechanical ventilation that can decrease PaCO2 during conventional mechanical ventilation and permissive hypercapnia.