Bronchial thermoplasty reduces airway resistance
Abstract Background The mechanism for symptomatic improvement after bronchial thermoplasty (BT) is unclear, since spirometry reveals little or no change. In this study, the effects of BT on airway resistance were examined using two independent techniques. Methods Eighteen consecutive patients, with...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2020-03-01
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| Series: | Respiratory Research |
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| Online Access: | http://link.springer.com/article/10.1186/s12931-020-1330-5 |
| _version_ | 1818863169300332544 |
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| author | David Langton Kim Bennetts Peter Noble Virginia Plummer Francis Thien |
| author_facet | David Langton Kim Bennetts Peter Noble Virginia Plummer Francis Thien |
| author_sort | David Langton |
| collection | DOAJ |
| description | Abstract Background The mechanism for symptomatic improvement after bronchial thermoplasty (BT) is unclear, since spirometry reveals little or no change. In this study, the effects of BT on airway resistance were examined using two independent techniques. Methods Eighteen consecutive patients, with severe asthma (57.6 ± 14.2 years) were evaluated by spirometry and plethysmography at three time points: (i) baseline, (ii) left lung treated but right lung untreated and (iii) 6 weeks after both lungs were treated with BT. At each assessment, total and specific airway resistance (Raw, sRaw) were measured. High resolution CT scans were undertaken at the first two assessments, and measurements of lobar volume, airway volume and airway resistance were made. The Asthma Control Questionnaire (ACQ) was administered at each assessment. Results The baseline ACQ score was 3.5 ± 0.9, and improved progressively to 1.8 ± 1.2 (p < 0.01). At baseline, severe airflow obstruction was observed, FEV1 44.8 ± 13.7% predicted, together with gas trapping, and elevated Raw at 342 ± 173%predicted. Following BT, significant improvements in Raw and sRaw were observed, as well as a reduction in Residual Volume, increase in Vital Capacity and no change in FEV1. The change in Raw correlated with the change in ACQ (r = 0.56, p < 0.05). CT scans demonstrated reduced airway volume at baseline, which correlated with the increased Raw determined by plethysmography (p = − 0.536, p = < 0.05). Following BT, the airway volume increased in the treated lung, and this was accompanied by a significant reduction in CT-determined local airway resistance. Conclusion Symptomatic improvement after BT is mediated by increased airway volume and reduced airway resistance. |
| first_indexed | 2024-12-19T10:11:29Z |
| format | Article |
| id | doaj.art-83ca895d75b141c5923976717c8012c8 |
| institution | Directory Open Access Journal |
| issn | 1465-993X |
| language | English |
| last_indexed | 2024-12-19T10:11:29Z |
| publishDate | 2020-03-01 |
| publisher | BMC |
| record_format | Article |
| series | Respiratory Research |
| spelling | doaj.art-83ca895d75b141c5923976717c8012c82022-12-21T20:26:21ZengBMCRespiratory Research1465-993X2020-03-012111810.1186/s12931-020-1330-5Bronchial thermoplasty reduces airway resistanceDavid Langton0Kim Bennetts1Peter Noble2Virginia Plummer3Francis Thien4Department of Thoracic Medicine, Frankston Hospital, Peninsula HealthDepartment of Thoracic Medicine, Frankston Hospital, Peninsula HealthSchool of Human Sciences, The University of Western AustraliaFaculty of Medicine, Nursing and Health Sciences, Monash UniversityFaculty of Medicine, Nursing and Health Sciences, Monash UniversityAbstract Background The mechanism for symptomatic improvement after bronchial thermoplasty (BT) is unclear, since spirometry reveals little or no change. In this study, the effects of BT on airway resistance were examined using two independent techniques. Methods Eighteen consecutive patients, with severe asthma (57.6 ± 14.2 years) were evaluated by spirometry and plethysmography at three time points: (i) baseline, (ii) left lung treated but right lung untreated and (iii) 6 weeks after both lungs were treated with BT. At each assessment, total and specific airway resistance (Raw, sRaw) were measured. High resolution CT scans were undertaken at the first two assessments, and measurements of lobar volume, airway volume and airway resistance were made. The Asthma Control Questionnaire (ACQ) was administered at each assessment. Results The baseline ACQ score was 3.5 ± 0.9, and improved progressively to 1.8 ± 1.2 (p < 0.01). At baseline, severe airflow obstruction was observed, FEV1 44.8 ± 13.7% predicted, together with gas trapping, and elevated Raw at 342 ± 173%predicted. Following BT, significant improvements in Raw and sRaw were observed, as well as a reduction in Residual Volume, increase in Vital Capacity and no change in FEV1. The change in Raw correlated with the change in ACQ (r = 0.56, p < 0.05). CT scans demonstrated reduced airway volume at baseline, which correlated with the increased Raw determined by plethysmography (p = − 0.536, p = < 0.05). Following BT, the airway volume increased in the treated lung, and this was accompanied by a significant reduction in CT-determined local airway resistance. Conclusion Symptomatic improvement after BT is mediated by increased airway volume and reduced airway resistance.http://link.springer.com/article/10.1186/s12931-020-1330-5Bronchial thermoplastyAsthmaAirway resistanceImaging |
| spellingShingle | David Langton Kim Bennetts Peter Noble Virginia Plummer Francis Thien Bronchial thermoplasty reduces airway resistance Respiratory Research Bronchial thermoplasty Asthma Airway resistance Imaging |
| title | Bronchial thermoplasty reduces airway resistance |
| title_full | Bronchial thermoplasty reduces airway resistance |
| title_fullStr | Bronchial thermoplasty reduces airway resistance |
| title_full_unstemmed | Bronchial thermoplasty reduces airway resistance |
| title_short | Bronchial thermoplasty reduces airway resistance |
| title_sort | bronchial thermoplasty reduces airway resistance |
| topic | Bronchial thermoplasty Asthma Airway resistance Imaging |
| url | http://link.springer.com/article/10.1186/s12931-020-1330-5 |
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