García-Sánchez M J, Polo A, Almazán A, Ramírez-Sánchez A, Palacio M A
Hospital General de Especialidades Ruiz de Alda, Ciudad Sanitaria Virgen de las Nieves, Granada.
Rev Esp Anestesiol Reanim. 1992 Mar-Apr;39(2):82-5.
We compare the degree of nitrous oxide diffusion in three types of endotracheal tubes available in the market, by means of continuous monitoring of the pressure attained at the pneumoballoon. Among the systems designed to impede or to minimize nitrous oxide diffusion, we have used in this study the so called "rediffusion system". When the endotracheal tube possesses this system, the pressure attained at the pneumoballoon remained constant throughout the study period (23.2 +/- 0.53 mmHg at time zero vs 24.2 +/- 0.66 mmHg 50 min after administration of protoxide). In contrast, endotracheal tubes without "rediffusion system" showed a statistically significant increase (p less than 0.05) of pneumoballoon pressure (25.2 +/- 2.43 mmHg and 26.7 +/- 1.01 mmHg at time zero vs 45.2 +/- 3.12 and 44.3 +/- 2.41 mmHg 50 min after protoxide administration in the two other types of endotracheal tubes). We believe that during anesthesia with nitrous oxide the pneumoballoon pressure should be monitored or systems that avoid diffusion of this inhalational agent should be inserted. Our results indicate that endotracheal tubes equiped with "rediffusion system" are effective in impeding diffusion of the inhalational agents.
我们通过持续监测气圈处达到的压力，比较了市场上三种类型气管内导管中氧化亚氮的扩散程度。在旨在阻碍或最小化氧化亚氮扩散的系统中，我们在本研究中使用了所谓的“再扩散系统”。当气管内导管具备该系统时，在整个研究期间气圈处达到的压力保持恒定（给药初始时为23.2±0.53 mmHg，给予氧化亚氮50分钟后为24.2±0.66 mmHg）。相比之下，没有“再扩散系统”的气管内导管显示气圈压力有统计学意义的增加（p<0.05）（在另外两种类型的气管内导管中，给药初始时分别为25.2±2.43 mmHg和26.7±1.01 mmHg，给予氧化亚氮50分钟后分别为45.2±3.12 mmHg和44.3±2.41 mmHg）。我们认为在氧化亚氮麻醉期间，应监测气圈压力或插入避免这种吸入剂扩散的系统。我们的结果表明，配备“再扩散系统”的气管内导管可有效阻碍吸入剂的扩散。
