Scott G C, Berger R, McKean H E
University of Missouri-Columbia Hospital and Clinics, Department of Pulmonary, Environmental and Critical Care Medicine 65212.
Am Rev Respir Dis. 1989 Mar;139(3):659-62. doi: 10.1164/ajrccm/139.3.659.
It has been postulated that spontaneous pneumothoraces (SP) develop because of rupture of subpleural blebs, and that atmospheric pressure changes (delta AP) may be contributory. A 5-year retrospective analysis of SP admissions was carried out to determine if delta AP do play a role in SP development. Using a 36-yr record of hourly delta AP, a normative background for delta AP was constructed. A fall in AP below the fifth, or a rise above the ninety-fifth percentile during these time periods, was classed as "unusual." Atmospheric pressure changes in the 4 days prior to SP were analyzed. The expected frequency of SP occurring by chance, if no relationship to delta AP existed, was also calculated. A total of 192 cases of SP was analyzed. Traumatic pneumothoraces were excluded. The majority of cases (72%) had been exposed to at least one "unusual" delta AP in the 4 days prior to onset of symptoms. Among those with four or more "unusual" exposures, SP occurrence was significantly more frequent than expected by chance alone (p less than 10(-10]. A strong positive association between delta AP and SP was not found in all cases, as delta AP are unlikely to be the only causative factor for SP. This finding of a relationship with ambient pressure changes lends support to the theory that SP develop as a result of rupture of subpleural blebs.
据推测，特发性气胸（SP）是由于胸膜下肺大疱破裂所致，大气压力变化（ΔAP）可能起一定作用。对特发性气胸入院病例进行了5年回顾性分析，以确定ΔAP是否在特发性气胸的发生中起作用。利用36年的每小时ΔAP记录，构建了ΔAP的正常背景。在这些时间段内，AP下降至第五百分位数以下或上升至第九十五百分位数以上被归类为“异常”。分析了特发性气胸发生前4天的大气压力变化。还计算了如果与ΔAP不存在关系，特发性气胸偶然发生的预期频率。共分析了192例特发性气胸病例，排除了创伤性气胸。大多数病例（72%）在症状出现前4天至少经历过一次“异常”的ΔAP。在有四次或更多“异常”暴露的患者中，特发性气胸的发生频率明显高于仅偶然预期的频率（p<10-10）。并非在所有病例中都发现ΔAP与特发性气胸之间有强正相关，因为ΔAP不太可能是特发性气胸的唯一致病因素。这一与环境压力变化相关的发现支持了特发性气胸是由于胸膜下肺大疱破裂所致的理论。
