Noninvasive Prediction of Twitch Transdiaphragmatic Pressure: Insights from Spirometry, Diaphragm Ultrasound, and Phrenic Nerve Stimulation Studies.

摘要: Background Twitch transdiaphragmatic pressure (twPdi) following magnetic stimulation (MS) of the phrenic nerves is gold standard for non-volitional assessment diaphragm strength. Expiratory muscle function can be investigated using MS abdominal muscles and measurement twitch gastric (twPgas). Objectives To investigate whether pressures lower thoracic nerve roots predicted noninvasively by ultrasound parameters volitional tests respiratory Methods Sixty-three healthy subjects underwent spirometry, maximum inspiratory (PImax) expiratory (PEmax), ultrasound. TwPdi cervical twPgas after (twPgas-Thor) were measured esophageal balloon catheters inserted transnasally. Using surface electrodes, compound action potentials (CMAP) simultaneously recorded from or obliquus abdominis muscles, respectively. Results Forced flow (FEF25-75) was significantly correlated with twPdi (r = 0.37; p 0.003) its components (twPgas pressure, twPes). Diaphragm excursion velocity during tidal breathing to twPes 0.44; 0.02). No prediction possible CMAP amplitude, forced vital capacity (FVC), PImax. TwPgas-Thor FEF25-75 0.46; 0.05) thickness at total lung 0.38; 0.04) but could not FVC, PEmax. Conclusions twPgas-Thor cannot measures strength, CMAP, Invasive recording remains indispensable objective