抽象
这项研究进行评估比例辅助通气(PAV)的生理作用,通过鼻罩无创给药,肺通气模式,动脉血气,肺力学,和吸气肌肉努力在稳定,高碳酸血症患者的慢性阻塞性肺病。在15例患者,PAV通过调整体积分别根据“失控”技术和患者的舒适性辅助(VA)和流动辅助(FA)设置。支持的程度固定在总的可能援助的80%,平均为13.9 +/- 4.1厘米水柱X L(-1),4.1 +/- 1.3厘米水柱X L(-1)×S个分别用于VA和FA。持续气道正压(CPAP),在2厘米水柱成立,然后增加到5厘米水柱。生理测量在CPAP上升之后自主呼吸(SB)期间进行的,经过40分钟的PAV,和20分钟。On average, PAV improved ventilation (10.3+/-2.1 to 12.5+/-2.0 L x m(-1)), tidal volume (0.60+/-0.11 to 0.76+/-0.24 L), arterial oxygen tension and arterial carbon dioxide pressure (from 6.7+/-0.7 to 7.1+/-0.9 and from 7.6+/-1.0 to 7.2+/-1.2 kPa, respectively). During SB, pulmonary resistance and dynamic lung elastance averaged 15.0+/-7.6 cmH2O x L(-1) s and 15.8+/-8.0 cmH2O x L(-1), respectively. Assuming a normal chest wall elastance (5 cmH2O x L(-1)), VA and FA relieved respectively approximately 70% of the elastic and 30% of the resistive burden, with PAV set with the procedure of this study. The overall magnitude of the patients' inspiratory effort, measured by means of the oesophageal and diaphragmatic pressure time product in 10 patients was significantly reduced by PAV, on average, 328+/-122 to 226+/-118 (-31%) and 361+/-119 to 254+/-126 (-30%) cmH2O x min(-1), respectively. In 10 patients the electrical activity of the diaphragm (Edi) was also reduced by PAV to approximately 70%, on average, of the SB activity. The rise of CPAP 25 cmH2O did not cause any further significant change in the physiological variables. In all instances there was a good patient-ventilator interaction, the ventilatory breath never entering into the patient's neural expiratory time. These data show that nasal proportional assist ventilation can provide physiological benefits to the stable hypercapnic chronic obstructive pulmonary disease patients. In fact, proportional assist ventilation, which was well tolerated by all patients, unloaded the inspiratory muscles and improved arterial blood gases. Further studies can clarify whether these beneficial physiological effects of nasal proportional assist ventilation can bear profitable consequences in the overall clinical management of chronic obstructive pulmonary disease patients with chronic carbon dioxide retention.