高频通气(HFV)是一种高通气频率和低潮气量的通气方式，其通气频率至少为机体正常呼吸频率的4倍，而潮气量近于或小于解剖死腔。其主要类型包括：高频正压通气、高频喷射通气和高频振荡通气等。其中，高频振荡通气(HFOV)是目前公认的最先进高频通气技术，在临床中应用最广泛。
急性肺损伤( ALI) 及急性呼吸窘迫综合征( ARDS) 是各种肺内外致病因素导致的急性呼吸衰竭, 以进行性呼吸困难和顽固性低氧血症为特征, 常继发于休克、创伤、严重感染以及大面积烧伤等疾病。病理以双肺弥漫性的渗出为特点。病情进展迅速, 预后极差, 具有很高死亡率。治疗时需要纠正缺氧, 以保证组织氧供。传统的常规机械通气( CMV) 在改善氧合、呼吸力学参数以及肺内炎症反应的同时, 导致肺损伤, 即呼吸机相关性肺损伤( VALI) 。近年认为, 采用高频振荡通气( HFOV) 代替CMV 能明显避免产生VALI, 并能改善ALI/ARDS的呼吸系统顺应性和氧合作用, 减轻肺内炎症反应和VALI, 利于急性损伤肺内塌陷和闭塞的小气道和肺泡重新开放。并且有人提出HFOV 与部分液体通气( PLV)联用( HFOV-PLV) 可进一步改善气体交换, 抑制肺组织的炎性反应, 减少肺损伤及氟碳化合物( PFCs) 用量, 稳定全身血液循环, 减少中枢神经系统( CNS) 并发症[ 1] 。
急性呼吸窘迫综合征( ARDS) 柏林定义指出: ARDS 以急性起病, 胸部X 线片示双肺弥漫性渗出性改变, 无左房高压的证据, 氧合指数≤300 mm Hg 为临床特征, 发病率及病死率高。几乎所有的 ARDS患者都需要机械通气治疗, 但是传统的通气模式及参数可能导致呼吸机相关性肺损伤 (VILI) , 主要包括气压伤, 容积伤和萎陷伤等。ARDS Network 的研究显示: 与大潮气量( 12 mL/ kg) 合并低呼气末正压 (PEEP) 的通气方式相比, 小潮气量( 6 mL/ kg) 合并高呼气末正压的肺保护性通气策略可以扩张陷闭的肺泡, 同时防止正常肺泡过度扩张, 从而降低肺损伤的发生率, 改善通气和氧合, 降低患者的死亡率。但是, 在实施肺保护性通气策略的基础上, 患者可能在较高的通气压力下仍然无法达到基本的通气和氧合目标, 所以死亡率仍然很高。高频振荡通气( HFOV) 以较快的频率( 成人180 ～600 次/min) 、较低的潮气量( 等于或略低于解剖死腔量) 和较高的平均气道压为特征, 也是一种肺保护性通气方式, 可作为传统通气方式的替代治疗, 降低ARDS患者的死亡率。
ObjectiveTo retrospectively compare the clinical effects of high frequency oscillatory ventilation (HFOV) and conventional ventilation (CV) on patients with acute respiratory distress syndrome (ARDS) induced by smoke inhalation injury. MethodsForty-three patients with smoke inhalation induced ARDS were admitted in the Center Hospital of Hu Ludao between October 2004 and June 2015.Among the patients, 19 cases were treated with CV (CV group) and 24 cases were treated with HFOV (HFOV group).The clinical data were collected and compared between two groups including blood gas at certain time points (6 h, 24 h, 48 h, 96 h, and 7 d) as well as complications and prognosis. ResultsThere was no significant difference in arterial blood gas between two groups before treatment (P > 0.05).After ventilation treatment, there were significant differences in arterial blood gas parameters between two groups except arterial carbon dioxide partial pressure at 48 and 96 h.And the patients in the HFOV group improved more obviously.The hospitalization time and ventilation time in the HFOV group were significantly shorter than those in the CV group (P < 0.05).No significant difference was found between two groups in the incidences of mortality, complications or 30-day survival rate (P > 0.05). ConclusionsBoth high frequency oscillatory ventilation and conventional ventilation can improve the clinical status in patients with smoke inhalation induced ARDS.These two ventilation modes do not present any difference with respect to prognosis by present evidence.