Establishment of noninvasive artificial ventilation in patients with sever lung edema

1. 正压通气（鼻持续气道正压通气）（研究1）将30例重度心源性肺水肿呼吸衰竭患者分为两组：吸氧加鼻腔CPAP组（CPAP组）和仅面罩吸氧组（氧气组）。CPAP组患者心率和平均肺动脉压明显降低。CPAP组6 h后PaO2/FiO2比值升高（163±70 ~ 332±104,p<0.01）。动脉血浆ET-1浓度与平均肺动脉压、Pao2/FIo2有显著相关性。（研究2）将连续22例患者随机分为以下两组：经鼻罩吸氧加CPAP组（CPAP组）和仅经面罩吸氧组（氧气组）。CPAP组2例（18%）、吸氧组8例（73%）需气管插管机械通气（p=0.03）。CPAP组住院死亡率（9%）明显低于吸氧组（64%,p=0.02）。CPAP组肺动脉楔压、平均肺动脉压、心率明显降低。插管组PaO2/FiO2比值明显升高。CPAP组动脉血浆内皮素-1浓度下降明显早于吸氧组（p<0.05）。鼻腔CPAP可早期改善氧合和血流动力学，降低死亡率。肺水肿患者建议进行早期积极的呼吸管理。负压通气（外高频振荡）（研究1）对7例上腹部手术后高碳酸血症患者采用EHFO通气。PaCO2明显降低。PaO2显著升高。FEV1和FVC显著升高。EHFO是一种有效的气体交换方法，与早期恢复术前肺功能有关。（研究2）12例患者采用EHFO联合PSV通气。心脏指数和脑卒中容量指数明显升高，但肺动脉楔压没有变化。PaO2/FiO2和PaCO2。采用EHFO后，整个肺区呼吸音都很困难。EHFO联合PSV作为急性呼吸衰竭患者的一种通气方法，在有利于分泌物引流的情况下，可能比传统机械通气有潜在的优势。EHFO的有益效果可能在几小时后出现。少

1. Positive pressure ventilation (Nasal continuous positive airway pressure)(Study 1) Thirty patients with respiratory failure due to severe cardiogenic puylmonary edema were assigned to two groups : received oxygen plus nasal CPAP (CPAP group), and received only oxygen by face mask (oxygen group). The heart rate and the mean pulmonary artery pressure decreased significantly in the CPAP group. The PaO2/FiO2 ratio increased in the CPAP group (163±70 to 332±104, p<0.01) after 6 hr. There was a significant correlation between the arterial plasma ET-1 concentrations and mean pulmonary artery pressure, and Pao2/FIo2.(Study 2) Tenty-two consecutive patients were assigned at random to either of the following two groups : received oxygen plus CPAP delivered by a nasal mask (CPAP group), and received only oxygen through face mask (oxygen group). Two patients (18%) in the CPAP group and 8 patients (73%) in the oxygen group required mechanical ventilation with endotracheal intubation (p=0.03). Th … More e hospital mortality rate in the CPAP group (9%) was significantly lower than the oxygen group (64%, p=0.02). The pulmonary artery wedge pressure, mean pulmonary artery pressure, and heart rate significantly decreased in the CPAP. The PaO2/FiO2 ratio significantly increased in the intubation group. Arterial plasma endothelin-1 concentrations decreased significantly earlier in the CPAP group than in the oxygen group (p<0.05). Nasal CPAP lead to an early improvement in oxygenation and hemodynamics, and decreased the mortality rate. Early and active respiratory management is recommended in patients with pulmonary edema.2. Negative pressure ventilation (External high-frequency oscillation)(Study 1) Seven patients with postoperative hypercapnia following upper abdominal surgery were ventilated with EHFO. PaCO2 significantly decreased. PaO2 significantly increased. The FEV1 and FVC significantly increased. EHFO is an effective method of gas exchange which is associated with earlier return to preoperative lung function.(Study 2) Twelve patients were ventilated with EHFO combined with PSV. Significant increases were noted in cardiac index and stroke volume index without changes in pulmonary artery wedge pressure. PaO2/FiO2 and PaCO2. Breath sounds could be hard well throughout the lung fields after institution of EHFO. As a method of ventilation for patients with acute respiratory failure, EHFO combined with PSV may have potential advantages over conventional mechanical ventilation when drainage of secretions is facilitated. Beneficial effects of EHFO may appear after several hours. Less