Objective. The aim of the present study was to evaluate sniff test, maximal inspiratory pressure, and presence of paradoxical inspiratory diaphragmatic movements and their diagnostic value in patients referred for suspicion of diaphragmatic dysfunction. Methods. Twenty-two patients (8 men and 14 women, years) with suspected diaphragmatic dysfunction were included. Pulmonary function test was evaluated by spirometry. Diaphragm dysfunction was diagnosed with unilateral phrenic nerve stimulation. Esophageal pressure was recorded during sniff test and maximal static inspiratory movements. Detection of paradoxical diaphragmatic movement was performed with anteroposterior projection of chest X-ray fluoroscopic video. Results. Phrenic nerve stimulation enabled diagnosis of diaphragmatic paralysis in 15 of the 22 patients. The remaining 7 patients had normal explorations. Lung volumes were significantly lower in patients with diaphragmatic paralysis than in control subjects, as maximal inspiratory pressure. No patient with normal diaphragmatic exploration had paradoxical inspiratory movement. The combined diagnostic value of reduced esophageal pressure during sniff test, reduced esophageal pressure during maximal static inspiratory movements, and presence of paradoxical inspiratory movement had a sensitivity of 87% and a specificity of 71%. Conclusion. Our results suggest that, in most cases, a combination of sniff test, maximal inspiratory pressure, and paradoxical inspiratory movement could help to diagnose diaphragmatic dysfunction. Nevertheless, phrenic nerve stimulation remains the best test for assessing diaphragmatic dysfunction. 1. Introduction Diaphragmatic paralysis is common and may be due to infectious, iatrogenic, or malignant causes, although the most common is frigore paralysis. Damage to the diaphragm or the phrenic nerve decreases inspiratory pressure, leading to diaphragmatic weakness and reduction in inspiratory muscle capacity [1] and lung volume, which in turn impair respiratory muscle endurance [2] and produce dyspnea [3]. Diaphragmatic dysfunction should thus be considered as a differential diagnosis of unexplained dyspnea, but its definitive diagnosis is difficult to assert. Definitive diagnosis can be obtained by phrenic nerve stimulation combined with measurement of twitch transdiaphragmatic pressure [4, 5], but the technique may be difficult in some patients. In clinical practice, suspicion of diaphragmatic paralysis is usually based on diaphragmatic curse during diaphragmatic fluoroscopic examination [6], inspiratory muscle strength
References
[1]
C. M. Laroche, A. K. Mier, J. Moxham, and M. Green, “Diaphragm strength in patients with recent hemidiaphragm paralysis,” Thorax, vol. 43, no. 3, pp. 170–174, 1988.
[2]
N. Hart, A. H. Nickol, D. Cramer et al., “Effect of severe isolated unilateral and bilateral diaphragm weakness on exercise performance,” American Journal of Respiratory and Critical Care Medicine, vol. 165, no. 9, pp. 1265–1270, 2002.
[3]
C. M. Laroche, N. Carroll, J. Moxham, and M. Green, “Clinical significance of severe isolated diaphragm weakness,” American Review of Respiratory Disease, vol. 138, no. 4, pp. 862–866, 1988.
[4]
M. Aubier, D. Murciano, Y. Lecocguic, N. Viires, and R. Pariente, “Bilateral phrenic stimulation: a simple technique to assess diaphragmatic fatigue in humans,” Journal of Applied Physiology, vol. 58, no. 1, pp. 58–64, 1985.
[5]
T. Similowsky, B. Fleury, S. Launois, H. P. Cathala, P. Bouche, and J.-P. Derenne, “Cervical magnetic stimulation (SMC). A new method of bilateral phrenic nerve stimulation usable in clinical practice,” Revue des Maladies Respiratoires, vol. 5, no. 6, pp. 609–614, 1988.
[6]
G. J. Gibson, “Diaphragmatic paresis: pathophysiology, clinical features, and investigation,” Thorax, vol. 44, no. 11, pp. 960–970, 1989.
[7]
E. Verin, J. Marie, C. Tardif, and P. Denis, “Spontaneous recovery of diaphragmatic strength in unilateral diaphragmatic paralysis,” Respiratory Medicine, vol. 100, no. 11, pp. 1944–1951, 2006.
[8]
P. H. Quanjer, G. J. Tammeling, J. E. Cotes, O. F. Pedersen, R. Peslin, and J. C. Yernault, “Lung volumes and forced ventilatory flows. Report Working Party Standardization of Lung Function Tests, European Community for Steel and Coal. Official Statement of the European Respiratory Society,” The European Respiratory Journal. Supplement, vol. 16, pp. 5–40, 1993.
[9]
A. Baydur, P. K. Behrakis, and W. A. Zin, “A simple method for assessing the validity of the esophageal balloon technique,” American Review of Respiratory Disease, vol. 126, no. 5, pp. 788–791, 1982.
[10]
F. Héritier, F. Rahm, P. Pasche, and J. Fitting, “Sniff nasal inspiratory pressure: a noninvasive assessment of inspiratory muscle strength,” American Journal of Respiratory and Critical Care Medicine, vol. 150, no. 6, part 1, pp. 1678–1683, 1994.
[11]
N. Syabbalo, “Assessment of respiratory muscle function and strength,” Postgraduate Medical Journal, vol. 74, no. 870, pp. 208–215, 1998.
[12]
C. Uldry and J.-W. Fitting, “Maximal values of sniff nasal inspiratory pressure in healthy subjects,” Thorax, vol. 50, no. 4, pp. 371–375, 1995.
[13]
F. D. McCool and G. E. Tzelepis, “Dysfunction of the diaphragm,” The New England Journal of Medicine, vol. 366, no. 10, pp. 932–942, 2012.
[14]
L. F. Black and R. E. Hyatt, “Maximal respiratory pressures: normal values and relationship to age and sex,” American Review of Respiratory Disease, vol. 99, no. 5, pp. 696–702, 1969.
[15]
C. Bruschi, I. Cerveri, M. C. Zoia et al., “Reference values of maximal respiratory mouth pressures: a population-based study,” American Review of Respiratory Disease, vol. 146, no. 3, pp. 790–793, 1992.
[16]
“ATS/ERS Statement on respiratory Muscle Testing,” American Journal of Respiratory and Critical Care Medicine, vol. 166, pp. 518–624, 2002.
[17]
T. Similowski, B. Fleury, S. Launois, H. P. Cathala, P. Bouche, and J. P. Derenne, “Cervical magnetic stimulation: a new painless method for bilateral phrenic nerve stimulation in conscious humans,” Journal of Applied Physiology, vol. 67, no. 4, pp. 1311–1318, 1989.
[18]
G. H. Mills, D. Kyroussis, C.-H. Hamnegard, S. Wragg, J. Moxham, and M. Green, “Unilateral magnetic stimulation of the phrenic nerve,” Thorax, vol. 50, no. 11, pp. 1162–1172, 1995.
[19]
M. J. Tobin, “Respiratory muscles in disease,” Clinics in Chest Medicine, vol. 9, no. 2, pp. 263–286, 1988.
[20]
G. H. Mills, D. Kyroussis, C. H. Hamnegard, M. I. Polkey, M. Green, and J. Moxham, “Bilateral magnetic stimulation of the phrenic nerves from an anterolateral approach,” American Journal of Respiratory and Critical Care Medicine, vol. 154, no. 4, part 1, pp. 1099–1105, 1996.
[21]
T. Similowski, C. Straus, V. Attali, A. Duguet, B. Jourdain, and J. Derenne, “Assessment of the motor pathway to the diaphragm using cortical and cervical magnetic stimulation in the decision-making process of phrenic pacing,” Chest, vol. 110, no. 6, pp. 1551–1557, 1996.
[22]
A. Teixeira, P. Cherin, A. Demoule et al., “Diaphragmatic dysfunction in patients with idiopathic inflammatory myopathies,” Neuromuscular Disorders, vol. 15, no. 1, pp. 32–39, 2005.
[23]
Y. M. Luo, N. Hart, N. Mustfa et al., “Reproducibility of twitch and sniff transdiaphragmatic pressures,” Respiratory Physiology and Neurobiology, vol. 132, no. 3, pp. 301–306, 2002.
[24]
J. Steier, S. Kaul, J. Seymour, et al., “The value of multiple tests of respiratory muscle strength,” Thorax, vol. 44, pp. 990–996, 1989.
[25]
T. Similowski, C. Straus, V. Attali, A. Duguet, and J. Derenne, “Cervical magnetic stimulation as a method to discriminate between diaphragm and rib cage muscle fatigue,” Journal of Applied Physiology, vol. 84, no. 5, pp. 1692–1700, 1998.
[26]
G. H. Mills, D. Kyroussis, C. Hamnegard et al., “Cervical magnetic stimulation of the phrenic nerves in bilateral diaphragm paralysis,” American Journal of Respiratory and Critical Care Medicine, vol. 155, no. 5, pp. 1565–1569, 1997.
[27]
J. M. Miller, J. Moxham, and M. Green, “The maximal sniff in the assessment of diaphragm function in man,” Clinical Science, vol. 69, no. 1, pp. 91–96, 1985.
[28]
C. M. Laroche, A. K. Mier, J. Moxham, and M. Green, “The value of sniff esophageal pressures in the assessment of global inspiratory muscle strenght,” American Review of Respiratory Disease, vol. 138, no. 3, pp. 598–603, 1988.
[29]
Y. F. Heijdra, P. N. R. Dekhuijzen, C. L. A. van Herwaarden, and H. T. M. Folgering, “Differences between sniff mouth pressures and static maximal inspiratory mouth pressures,” European Respiratory Journal, vol. 6, no. 4, pp. 541–546, 1993.
[30]
F. Heritier, C. Perret, and J.-W. Fitting, “Maximal sniff mouth pressure compared with maximal inspiratory pressure in acute respiratory failure,” Chest, vol. 100, no. 1, pp. 175–178, 1991.
[31]
E. A. Lennon and G. Simon, “The height of the diaphragm in the chest radiograph of normal adults,” British Journal of Radiology, vol. 38, no. 456, pp. 937–943, 1965.
[32]
D. A. Young and G. Simon, “Certain movements measured on inspiration-expiration chest radiographs correlated with pulmonary function studies,” Clinical Radiology, vol. 23, no. 1, pp. 37–41, 1972.
[33]
I. Y. Ch'en and J. D. Armstrong II, “Value of fluoroscopy in patients with suspected bilateral hemidiaphragmatic paralysis,” American Journal of Roentgenology, vol. 160, no. 1, pp. 29–31, 1993.
[34]
J. G. Houston, M. Fleet, M. D. Cowan, and N. C. McMillan, “Comparison of ultrasound with fluoroscopy in the assessment of suspected hemidiaphragmatic movement abnormality,” Clinical Radiology, vol. 50, no. 2, pp. 95–98, 1995.
