Chest
Volume 90, Issue 6, December 1986, Pages 822-826
Journal home page for Chest

Clinical Investigations
Comparison of Bronchial Responses to Ultrasonically Nebulized Distilled Water, Exercise, and Methacholine in Asthma

https://doi.org/10.1378/chest.90.6.822Get rights and content

We compared the responses to inhaled methacholine, ultrasonically nebulized distilled water, and exercise in 25 subjects with atopic asthma. The methacholine inhalation test and challenges with distilled water and exercise were performed on three separate days 48 hours apart. Bronchial responsiveness to methacholine and ultrasonically nebulized distilled water was measured as the concentration of methacholine (PC20M) and the volume output of the ultrasonic nebulizer (PO20 UNDW) producing a 20 percent fall in the forced expiratory volume in one second (FEV1). The response to exercise was expressed as the percentage of fall in FEV1 from the value before exercise. Seventeen subjects showed a fall in FEV1 of more than 20 percent after exercise. Eight subjects had a stimulus-response curve to distilled water that was flat up to the maximal volume output from the nebulizer, but only four of them also showed no significant response to exercise. The response to exercise correlated better with PO20UNDW (r= –0.66; p<0.01) than with PC20M (r= –0.19; p>0.5) in those responding to distilled water. In all of the tested subjects, exercise-induced bronchoconstriction correlated with PC20M (r=–0.61; p<0.01). The mean PC20M was significantly lower in the subjects with a significant response to distilled water and exercise (p<0.001 and p<0.0001, respectively). We concluded that ultrasonically nebulized distilled water and exercise provoke significant bronchoconstriction in the subjects with more severe nonspecific bronchial hyperresponsiveness. The correlation found between the two stimuli supports the hypothesis that they act by similar mechanisms.

Section snippets

MATERIALS AND METHODS

The group of asthmatic subjects studied comprised 19 male and six female subjects (age range, 9 to 19 years). The criteria for selection were a characteristic clinical history of asthma,20 an initial forced expiratory volume in one second (FEV1) of more than 70 percent of the predicted normal,21 and a range of bronchial responsiveness to inhaled methacholine from slightly to severely increased.3 No attempt was made to select subjects on the basis of a history of exercise-induced asthma. All

RESULTS

There was no significant difference in baseline FEV1 (as percent predicted) on the three days of study by analysis of variance (mean FEV1 before methacholine, 93.8±10.6 (±5D); mean FEV1 before exercise, 91.6 ±9.2; mean FEV1 before distilled water, 90.8 ± 9.7; p>0.5), and in each subject, baseline FEV1 varied by less than 10 percent (Table 1).

Seventeen out of 25 subjects showed a fall in FEV1 greater than 20 percent after exercise (Table 1). In eight subjects the stimulus-response curve with

DISCUSSION

The results of the present study show that both inhaled ultrasonically nebulized distilled water and exercise are effective bronchoconstrictor stimuli in subjects with more severe asthma. In fact, the level of nonspecific bronchial responsiveness, as measured by methacholine challenge, was significantly lower in the subjects who had a response to distilled water and exercise; these subjects also had a longer asthmatic history. In our patients the response to distilled water did not correlate

REFERENCES (40)

  • L Allegra et al.

    Non specific broncho-reactivity obtained with ultrasonic mist aerosol of distilled water

    Eur J Respir Dis

    (1980)
  • RE Schoeffel et al.

    Bronchial hyperreactivity in response to inhalation of ultrasonically nebulized solution of distilled water and saline

    Br Med J

    (1981)
  • T Higenbottam et al.

    Bronchial reactivity in asthmatic adults with normal spirometry values

    Br Med J

    (1983)
  • T Sheppard et al.

    Mechanism of cough and bronchoconstriction induced by distilled water aerosol

    Am Rev Respir Dis

    (1983)
  • F Mormile et al.

    Allergen-induced increase in non-allergic bronchial responsiveness to ultrasonic mist

    Prog Respir Res

    (1985)
  • J Kiviloog

    Bronchial reactivity to exercise and methacholine in bronchial asthma

    Scand J Respir Dis

    (1973)
  • J Kiviloog

    The correlation between exercise-induced bronchoconstriction and bronchial sensitivity in asthma

    Pediatrics

    (1975)
  • CM Mellis et al.

    Comparative study of histamine and exercise challenges in asthmatic children

    Am Rev Respir Dis

    (1979)
  • JA Fleetham et al.

    Cough and bronchoconstriction in response to inhaled citric acid, distilled water and methacholine

    Am Rev Respir Dis

    (1983)
  • LM Fabbri et al.

    Comparison of ultrasonically nebulized distilled water and hyperventilation with cold air in asthma

    Ann Allergy

    (1984)
  • Cited by (62)

    • Psychological status and quality of life in elderly patients with asthma

      2005, Psychosomatics
      Citation Excerpt :

      Histamine solution (diphosphate salt, Sigma, Diesenhofen, Germany) was prepared in sterile isotonic saline. The histamine challenge test was performed according to a standardized procedure.18 Pulmonary functions were measured with a flow-sensing spirometer connected to a computer.

    View all citing articles on Scopus

    Manuscript received March 10; revision accepted May 8.

    View full text