Sniff nasal inspiratory pressure (SNIP) is used to assess respiratory muscle strength in neuromuscular diseases like amyotrophic lateral sclerosis (ALS). The effect of contralateral nostril occlusion and mouth sealing on SNIP measurement are unclear. 81 participants were included (16 healthy, 39 patients with limb-onset ALS and 26 patients with bulbar-onset ALS). SNIP was obtained with combinations of mouth open/sealed and contralateral nostril open/occluded. Occluding the contralateral nostril (with mouth closed) increased SNIP by 12 cmH2O (95% CI 4, 20; p=0.003) in the healthy participants, by 9 cmH2O (95% CI 5, 12; p<0.001) in the limb-onset cohort and by 10 cmH2O (95% CI 5, 14; p<0.001) in the bulbar-onset cohort. Opening the mouth decreased SNIP by 19 cmH2O (95% CI 5, 34; p<0.009) in healthy participants, by 8 cmH2O (95% CI 4, 13; p<0.001) in the limb-onset cohort and by 13 cmH2O (95% CI 7, 19; p<0.001) in the bulbar-onset cohort. With contralateral nostril occlusion, 11% fewer individuals would have qualified for non-invasive ventilation. In conclusion, contralateral nostril occlusion increased SNIP compared with standard technique, likely reflecting true strength. Opening the mouth reduced SNIP, emphasising the need for good mouth sealing. Documenting SNIP technique is important for longitudinal assessments and clinical decision-making.

中文翻译：

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鼻孔阻塞和封口对嗅鼻吸气压测量的影响


嗅鼻吸气压 （SNIP） 用于评估肌萎缩侧索硬化症 （ALS） 等神经肌肉疾病中的呼吸肌力量。对侧鼻孔阻塞和口腔密封对 SNIP 测量的影响尚不清楚。纳入 81 名参与者 （16 名健康患者、39 名肢体发病的 ALS 患者和 26 名延髓发病的 ALS 患者）。SNIP 是通过张口/密封和对侧鼻孔张开/闭塞的组合获得的。闭塞对侧鼻孔（闭口）使健康参与者的 SNIP 增加了 12 cmH2O（95% CI 4,20;p=0.003），肢体发作队列增加了 9 cmH2O（95% CI 5,12;p<0.001），延髓发作队列增加了 10 cmH2O（95% CI 5,14;p<0.001）。在健康参与者中，张口使 SNIP 减少了 19 cmH2O （95% CI 5， 34;p<0.009），在肢体发作队列中减少了 8 cmH2O （95% CI 4， 13;p<0.001），在延髓发作队列中降低了 13 cmH2O （95% CI 7， 19;p<0.001）。对于对侧鼻孔阻塞，符合无创通气条件的个体减少 11%。总之，与标准技术相比，对侧鼻孔阻塞增加了 SNIP，可能反映了真实强度。张口减少了 SNIP，强调了良好口腔密封的必要性。记录 SNIP 技术对于纵向评估和临床决策很重要。