It is claimed that lung volume reduction surgery (LVRS) improves inspiratory muscle function. As diaphragm structure and function are not directly appraisable in patients, we studied the effects of LVRS on the diaphragm in vitro contractile properties and morphology in hamsters with elastase-induced emphysema. Four months after intratracheal instillation of elastase (40 U/100 g), hamsters underwent either bilateral LVRS (LVRS, n = 11) or a sham operation (SHAM, n = 8). Four animals died during the perioperative period in LVRS (n = 7). Hamsters instilled with saline served as control (CTL, n = 8). Animals were studied at the age of 9 mo. LVRS was associated with a significant 25% decrease in functional residual capacity compared to SHAM (p < 0.05). Compared with CTL, LVRS and SHAM showed a significant 18% and 14% reduction in diaphragm mass, respectively (p = 0.02). LVRS had a significantly decreased twitch tension compared to CTL and SHAM (p < 0.01). Both LVRS and SHAM showed increased resistance to muscle fatigue compared with CTL. The histochemical analysis revealed a significant shift from type IIx/b toward type IIa fibers in LVRS and SHAM compared with CTL. In conclusion, emphysema is associated with functional adaptations but LVRS does not appear to beneficially alter the diaphragm contractile and morphological characteristics in hamsters with elastase-induced emphysema.
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http://dx.doi.org/10.1164/ajrccm.162.3.9911096 | DOI Listing |
Minerva Med
August 2015
Centre of Respiratory Endoscopy and Laser‑Theraphy, A.O. Spedali Civili di Brescia, Brescia, Italy -
Lung volume reduction coil (LVRC) treatment is a minimally-invasive technique planned to achieve an improvement of exercise capacity and pulmonary function in subjects with advanced emphysema and hyperinflation. It has been proposed together with other bronchoscopic lung volume reduction approaches to reduce lung hyperinflation in emphysema as less invasive alternatives to LVRS and are currently under clinical investigation. Following the successful early experiences in previous pilot trials, recent studies allow further investigation into the feasibility, safety and efficacy of LVR coil treatment in a multi-center setting in a larger group of patients.
View Article and Find Full Text PDFMinerva Med
July 2015
Centre Of Respiratory Endoscopy and Laser‑theraphy A.O. Spedali Civili di Brescia, Brescia, Italy -
Lung volume reduction coil (LVRC) treatment is a minimally-invasive technique planned to achieve an improvement of exercise capacity and pulmonary function in subjects with advanced emphysema and hyperinflation. It has been proposed together with other bronchoscopic lung volume reduction approaches to reduce lung hyperinflation in emphysema as less invasive alternatives to LVRS and are currently under clinical investigation. Following the successful early experiences in previous pilot trials, recent studies allow further investigation into the feasibility, safety and efficacy of LVR coil treatment in a multi-center setting in a larger group of patients.
View Article and Find Full Text PDFSurg Today
December 2005
Second Department of Surgery, Hokkaido University Hospital, Sapporo 060-8648, Japan.
Purpose: We performed lung volume reduction surgery (LVRS) in an experimental model using a simple stapling technique (SST) for pulmonary emphysema. The technique uses a stapler to isolate the affected lung from the remaining lung instead of removing it. We performed the present experiment using dogs to study the effects and safety of LVRS using the SST.
View Article and Find Full Text PDFAm J Respir Crit Care Med
October 2004
Division of Pulmonary/Critical Care Medicine, Cedars-Sinai Medical Center, David Geffen School of Medicine at University of California, Los Angeles, CA 90048, USA.
With emphysema, diaphragm length adaptation results in shortened fibers. We hypothesize that passive diaphragm stretch occurring acutely after lung volume reduction surgery (LVRS) results in fiber injury. Bilateral LVRS was performed in emphysematous hamsters.
View Article and Find Full Text PDFEur Respir J
June 2002
Respiratory Muscle Research Unit, University Hospitals, Katholieke Universiteit Leuven, Belgium.
Unlabelled: The authors have demonstrated previously that emphysema and lung volume reduction surgery (LVRS) resulted in a significant shift of type IIx/b to type IIa fibres in the diaphragm of hamsters with elastase-induced emphysema. To explore the mechanisms leading to this fibre switching, the mRNA expression of the myogenic regulatory factors, the inhibitors of DNA binding proteins (Id-proteins) and insulin-like growth factor-I were examined. Ribonucleic acid was extracted from the diaphragm of control, emphysematous, emphysematous and sham operated and LVRS hamsters and subjected to reverse transcriptase polymerase chain reaction.
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