Sancho Jesús, Servera Emilio, Díaz Juan, Marín Julio
Department of Respiratory Medicine, Hospital Clínico Universitario, Universitat de València, Valencia, Spain.
Chest. 2004 Apr;125(4):1400-5. doi: 10.1378/chest.125.4.1400.
To determine under what circumstances the use of mechanical insufflation-exsufflation (MI-E) can generate clinically effective expiratory flows for airway clearance (> 2.7 L/s) for clinically stable patients with amyotrophic lateral sclerosis (ALS).
Twenty-six consecutive patients with ALS were studied, 15 with severe bulbar dysfunction. Using a pneumotachograph and with the aid of an oronasal mask, we measured FVC, FEV(1), peak cough flow (PCF), maximum insufflation capacity (MIC), PCF generated from a maximum insufflation MIC (PCFMIC), and PCF generated by MI-E (PCFMI-E). MI-E was delivered at +/- 40 cm H(2)O. Maximum inspiratory pressure (PImax) and maximum expiratory pressure (PEmax) at the mouth were also measured.
Although both groups had a similar time from ALS symptom onset to diagnosis, statistical differences (p < 0.05) were found between nonbulbar and bulbar patients in lung function and cough capacity parameters: FVC, 2.58 +/- 1.24 L vs 1.62 +/- 0.74 L; FEV(1), 2.26 +/- 1.18 L vs 1.54 +/- 0.69 L; PImax, - 93.45 +/- 47.47 cm H(2)O vs - 3.64 +/- 25.07 cm H(2)O; PEmax, 140.45 +/- 75.98 cm H(2)O vs 69.93 +/- 32.14 cm H(2)O; MIC, 3.02 +/- 1.22 L vs 1.97 +/- 0.75 L; PCF, 5.91 +/- 2.55 L/s vs 3.42 +/- 1.44 L/s; PCFMIC, 6.68 +/- 2.71 L/s vs 4.00 +/- 1.48 L/s; and PCFMI-E, 4.34 +/- 0.82 L/s vs 3.35 +/- 0.77 L/s. Four patients with bulbar dysfunction and MIC > 1 L had PCFMI-E < 2.7 L/s. The receiver operating characteristic (ROC) curve analysis showed PCFMIC of <or= 2.7 L/s predicting those patients with PCFMI-E < 2.7 L/s. The ROC curve analysis showed PCFMIC > 4 L/s predicting those patients with PCFMIC greater than PCFMI-E.
MI-E is able to generate clinically effective PCFMI-E (> 2.7 L/s) for stable patients with ALS, except for those with bulbar dysfunction who also have a MIC > 1 L and PCFMIC <2.7 L/s who probably have severe dynamic collapse of the upper airways during the exsufflation cycle. Clinically stable patients with mild respiratory dysfunction and PCFMIC > 4 L/s might not benefit from MI-E except during an acute respiratory illness.
确定在何种情况下，对于临床症状稳定的肌萎缩侧索硬化症（ALS）患者，使用机械吸气-呼气（MI-E）能产生临床上有效的呼气流量用于气道清理（>2.7升/秒）。
对26例连续的ALS患者进行研究，其中15例有严重延髓功能障碍。使用呼吸流速仪并借助口鼻面罩，我们测量了用力肺活量（FVC）、第1秒用力呼气量（FEV₁）、峰值咳嗽流量（PCF）、最大吸气容量（MIC）、由最大吸气MIC产生的PCF（PCFMIC）以及由MI-E产生的PCF（PCFMI-E）。MI-E以±40厘米水柱的压力进行。还测量了口腔处的最大吸气压力（PImax）和最大呼气压力（PEmax）。
尽管两组从ALS症状出现到诊断的时间相似，但在肺功能和咳嗽能力参数方面，非延髓型和延髓型患者之间存在统计学差异（p<0.05）：FVC，2.58±1.24升对1.62±0.74升；FEV₁，2.26±1.18升对1.54±0.69升；PImax，-93.45±47.47厘米水柱对-3.64±25.07厘米水柱；PEmax，140.45±75.98厘米水柱对69.93±32.14厘米水柱；MIC，3.02±1.22升对1.97±0.75升；PCF，5.91±2.55升/秒对3.42±1.44升/秒；PCFMIC，6.68±2.71升/秒对4.00±1.48升/秒；以及PCFMI-E，4.34±0.82升/秒对3.35±0.77升/秒。4例有延髓功能障碍且MIC>1升的患者PCFMI-E<2.7升/秒。受试者工作特征（ROC）曲线分析显示，PCFMIC≤2.7升/秒可预测那些PCFMI-E<2.7升/秒的患者。ROC曲线分析显示，PCFMIC>4升/秒可预测那些PCFMIC大于PCFMI-E的患者。
对于临床症状稳定的ALS患者，MI-E能够产生临床上有效的PCFMI-E（>2.7升/秒），但对于那些有延髓功能障碍且MIC>1升且PCFMIC<2.7升/秒的患者除外，这类患者在呼气阶段可能存在上呼吸道严重动态塌陷。临床症状稳定且有轻度呼吸功能障碍且PCFMIC>4升/秒的患者，可能除了在急性呼吸道疾病期间外，无法从MI-E中获益。
