Chest
Volume 131, Issue 2, February 2007, Pages 368-375
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Original Research: Lung Function Testing
Lung Function Accurately Predicts Hypercapnia in Patients With Duchenne Muscular Dystrophy

https://doi.org/10.1378/chest.06-1265Get rights and content

Abstract

Background:In patients with Duchenne muscular dystrophy (DMD), implementation of mechanical ventilation depends on sleep investigation and measurement of CO2tension. The objective of this cross-sectional study was to determine which noninvasive lung function parameter best predicts nocturnal hypercapnia and diurnal hypercapnia in these patients.

Methods:According to transcutaneous CO2(Tcco2) measurement, 114 DMD patients were classified into three groups: nocturnal hypercapnia (n = 38) [group N], diurnal hypercapnia (n = 39), despite nocturnal ventilation (group D), and 24-h normocapnia and spontaneous breathing (n = 37) [group S] as control. Tcco2tension and lung function variables included vital capacity (VC) and maximal inspiratory pressure (MIP), and breathing pattern variables included tidal volume (Vt) and respiratory rate (RR), measured at the time of group inclusion. The rapid and shallow breathing index (RSBI [RR/Vt]) and Vt/VC ratio were calculated. Areas under the curve from the receiver operating characteristic (ROC) were calculated for those parameters.

Results:Compared to group S, lung function was significantly worse in group N and group D. VC, RR, and RSBI distinguished group S from group N by ROC comparison. Cut-off values of VC ≤ 680 mL (ROC, 0.968), MIP ≤ 22 cm H2O (ROC, 0.928), and Vt/VC > 0.33 (ROC, 0.923) accurately discriminated group D from group N, but RSBI, RR, and Vtdid not.

Conclusions:Lung function is useful to predict nocturnal hypercapnia in patients with DMD. Moreover, VC < 680 mL is very sensitive to predict daytime hypercapnia.

Section snippets

Study Design

Patients who met inclusion criteria for one of the groups on this study were followed up at our center. These patients were included in the present cross-sectional study. Patients were systematically assessed every 6 months during a 24-h scheduled hospital admission.

Patients

During the period from January 1, 1995, until December 31, 2004, 168 DMD patients were referred to Hospital Inkendaal, a specialist center for patients with neuromuscular disease. Study inclusion criteria comprised wheelchair-bound

Results

Table 1reports patient characteristics from group S, group N, and group D. The mean height was similar in the three groups. Despite the older age, VC and Vtwere progressively lower in the three groups (p < 0.001). The patients breathed shallower and more rapidly in group N compared to group S (p < 0.05), but this pattern was not different from group D. The VC, Vt, MIP, Vt/VC ratio, Ve, and BMI but not RR and RSBI were significantly lower in group D compared to group N. Finally, the Veat rest

Discussion

The present study suggests that patients with DMD remain normocapnic as long as VC remains > 1,820 mL. If VC drops below this value, nocturnal hypercapnia is likely to be present. If VC further decreases to < 680 mL, patients may start to be hypercapnic by the end of the day despite treatment with effective N-NIPPV. Hypercapnia during the night (yielding N-NIPPV) and during the day (requiring D-NIPPV) is not entirely obtained from the same variables.

In DMD, distinction should be made between

References (34)

  • A Hahn et al.

    Clinical implications of maximal respiratory pressure determinations for individuals with Duchenne muscular dystrophy.

    Arch Phys Med Rehabil

    (1997)
  • Y Rideau et al.

    Respiratory function in the muscular dystrophies.

    Muscle Nerve

    (1981)
  • M Estenne et al.

    Chest wall stiffness in patients with chronic respiratory muscle weakness.

    Am Rev Respir Dis

    (1983)
  • P Begin et al.

    Relationship between chronic hypercapnia and inspiratory-muscle weakness in myotonic dystrophy.

    Am J Respir Crit Care Med

    (1997)
  • M Vitacca et al.

    Breathing pattern and respiratory mechanics in patients with amyotrophic lateral sclerosis.

    Eur Respir J

    (1997)
  • F Garcia-Rio et al.

    Breathing pattern and central ventilatory drive in mild and moderate generalised myasthenia gravis.

    Thorax

    (1994)
  • JC Chevrolet et al.

    Repeated vital capacity measurements as predictive parameters for mechanical ventilation need and weaning success in the Guillain-Barré syndrome.

    Am Rev Respir Dis

    (1991)
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    This work was performed at Inkendaal Rehabilitation Hospital, Neuromuscular Centre VUB-Inkendaal and Centre for Home Mechanical Ventilation.

    The authors have no conflicts of interest to disclose.

    Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestjournal.org/misc/reprints.shtml).

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