Shivaram U, Miro A M, Cash M E, Finch P J, Heurich A E, Kamholz S L
Department of Medicine, Brooklyn VA Medical Center, NY 11209.
J Crit Care. 1993 Jun;8(2):87-92. doi: 10.1016/0883-9441(93)90012-a.
The effects of nasal continuous positive airway pressure (CPAP) on expiratory flow, arterial blood gas tensions, cardiovascular status, and dyspnea were studied in 21 patients with acute asthma. Therapy consisted of the following CPAP sequence: 30 minutes at 5 cm H2O, 20 minutes at 0 cm H2O, 30 minutes at 7.5 cm H2O, and 20 minutes at 0 cm H2O. Six control patients were fitted with a CPAP mask but given no positive-pressure therapy. Significant reductions in respiratory rate occurred from a baseline of 22.0 +/- 1.0 to 19.8 +/- 3.8 breaths/min at CPAP 5 cm H2O and to 19.4 +/- 4.3 breaths/min at CPAP 7.5 cm H2O (P < .05). No significant change occurred in forced expiratory volume in 1 second (FEV1), heart rate, mean arterial blood pressure, or arterial blood gas tension with either level of CPAP. Dyspnea, as assessed by a breathlessness score, improved during CPAP therapy (P < .05). These levels of CPAP were tolerated without deleterious side effects. In comparison, the control group showed no change in heart rate, respiratory rate, or breathlessness score during the study period. These data show that application of CPAP in acute asthma reduces respiratory rate and dyspnea with no untoward effects on gas exchange, expiratory airflow, or hemodynamics.
对21例急性哮喘患者研究了鼻持续气道正压通气（CPAP）对呼气流量、动脉血气张力、心血管状态和呼吸困难的影响。治疗采用以下CPAP序列：5 cm H₂O通气30分钟，0 cm H₂O通气20分钟，7.5 cm H₂O通气30分钟，0 cm H₂O通气20分钟。6例对照患者佩戴CPAP面罩但未给予正压通气治疗。呼吸频率从基线的22.0±1.0次/分钟显著降低至CPAP 5 cm H₂O时的19.8±3.8次/分钟以及CPAP 7.5 cm H₂O时的19.4±4.3次/分钟（P<0.05）。两种CPAP水平下，一秒用力呼气量（FEV₁）、心率、平均动脉血压或动脉血气张力均无显著变化。通过呼吸困难评分评估，CPAP治疗期间呼吸困难有所改善（P<0.05）。这些CPAP水平可耐受，无有害副作用。相比之下，对照组在研究期间心率、呼吸频率或呼吸困难评分均无变化。这些数据表明，在急性哮喘中应用CPAP可降低呼吸频率和呼吸困难，且对气体交换、呼气气流或血流动力学无不良影响。
