The effect of posture on asynchronous chest wall movement in COPD

Rita Priori, Andrea Aliverti, André L. Albuquerque, Marco Quaranta, Paul Albert, and Peter M. A. Calverley 


Chronic obstructive pulmonary disease (COPD) patients often show asynchronous movement of the lower rib cage during spontaneous quiet breathing and exercise. We speculated that varying body position from seated to supine would influence rib cage asynchrony by changing the configuration of the respiratory muscles. Twenty-three severe COPD patients (forced expiratory volume in 1 s = 32.5±7.0% predicted) and 12 healthy age-matched controls were studied. Measurements of the phase shift between upper and lower rib cage and between upper rib cage and abdomen were performed with opto-electronic plethysmography during quiet breathing in the seated and supine position. Changes in diaphragm zone of apposition were measured by ultrasounds. Control subjects showed no compartmental asynchronous movement, whether seated or supine. In 13 COPD patients, rib cage asynchrony was noticed in the seated posture. This asynchrony disappeared in the supine posture. In COPD, upper rib cage and abdomen were synchronous when seated, but a Strong asynchrony was found in supine. The relationships between changes in diaphragm zone of apposition and volume variations of chest wall compartments supported these findings. Rib cage paradox was noticed in approximately one-half of the COPD patients while seated, but was not related to impaired diaphragm motion. In the supine posture, the rib cage paradox disappeared, suggesting that, in this posture, diaphragm mechanics improves. In conclusion, changing body position induces importante differences in the chest wall behavior in COPD patients.

Variations of Thoracoabdominal Volumes After Lung Transplantation Measured by Opto-Electronic Plethysmography

M. Nosotti, M. Laviola, S. Mariani, E. Privitera, P. Mendogni, I.F. Nataloni, A. Aliverti, and L. Santambrogi


Background. Lung function after lung transplantation (LTx) has been widely studied. On the contrary, the thoracoabdominal volume rearrangement after LTx has yet to be investigated. Methods. Patients with cystic fibrosis and listed for double LTx at our institution were enrolled for the prospective study to explore the effects of LTx on the rearrangement of respiratory volumes in patients affected by cystic fibrosis, by utilizing the opto-electronic plethysmography (OEP), a noninvasive method to study the volume and motion of the human trunk. Rib cage and abdominal volumes were tested with OEP (OEP system, BTS, Milano, Italy). Results. Eight patients were enrolled (male-to-female ratio: 1:3; mean age 29.3 _ 7.8 years). After LTx the volume changes analyzed with OEP revealed a significant decrease of the total lung capacity (TLC) as well as the functional residual capacity and residual volume when the chest wall volume was considered. Dividing the whole respiratory volume in the three compartments showed different trends. Conclusions. We consider OEP a particularly useful device in patients with severe respiratory disease, in that it allows a noninvasive estimate of the volume change of the chest wall. This study demonstrates a significant reduction of thoracoabdominal volumes in patients affected by cystic fibrosis treated with bilateral LTx. Abdomen and upper rib cage were congruent with the volume reduction, while the lower rib cage showed an opposite tendency.

Chest wall regional volumes in obese women

Jacqueline de Melo Barcelar, Andrea Aliverti, Talita Lourdes Lins de Barros Melo, Camila Soares Dornelas, Catarina Souza Ferreira Rattes Lima, Cyda Maria A. Reinaux, Armèle Dornelas de Andrade


Excess body fat, particularly in the abdominal region, is responsible for respiratory system alterations.To study if and how both lung function and thoraco-abdominal volume variations during quiet breathingare altered in obese women and to determine if different obesity patterns in women have an influence onlung and chest wall function, 30 obese women (BMI ≥ 40 kg/m2) with both central and peripheral obesitywere studied by spirometry and opto-electronic plethysmography during quiet breathing and comparedwith normoweight women.Compared to controls, obese were characterized by lung restriction and higher minute ventilationat rest. Pulmonary rib cage tidal volume variations were significantly lower and abdominal volumevariations higher in obese women. No differences were found between central and peripheral obesewomen.In conclusion, in obese women, independently if obesity is central or peripheral, both lung functionand thoraco-abdominal pattern during spontaneous breathing are strongly altered. The amount of fat inthe abdominal compartment, and not the peripheral, alters the respiratory system.

Comparison of superimposed high-frequency jet ventilation with conventional jet ventilation for laryngeal surgery

R. Leiter, A. Aliverti, R. Priori, P. Staun, A. Lo Mauro, A. Larsson, P. Frykholm


Background. New ventilators have simplified the use of supraglottic superimposed highfrequency jet ventilation (SHFJVSG), but it has not been systematically compared with other modes of jet ventilation (JV) in humans. We sought to investigate whether SHFJVSG would provide more effective ventilation compared with single-frequency JV techniques. Methods. A total of 16 patients undergoing minor laryngeal surgery under general anaesthesia were included. In each patient, four different JV techniques were applied in random order for 10-min periods: SHFJVSG, supraglottic normal frequency (NFJVSG), supraglottic high frequency (HFJVSG), and infraglottic high-frequency jet ventilation (HFJVIG). Chest wall volume variations were continuously measured with opto-electronic plethysmography (OEP), intratracheal pressure was recorded and blood gases were measured. Results. Chest wall volumes were normalized to NFJVSG end-expiratory level. The increase in end-expiratory chest wall volume (EEVCW) was 239 (196) ml during SHFJVSG (P,0.05 compared with NFJVSG). EEVCW was 148 (145) and 44 (106) ml during HFJVSG and HFJVIG, respectively (P,0.05 compared with SHFJVSG). Tidal volume (VT) during SHFJVSG was 269 (149) ml. VT was 229 (169) ml (P¼1.00 compared with SHFJVSG), 145 (50) ml (P,0.05), and 110 (33) ml (P,0.01) during NFJVSG, HFJVSG, and HFJVIG, respectively. Intratracheal pressures corresponded well to changes in both EEVCW and VT. All JV modes resulted in adequate oxygenation. However, PaCO2 was lowest during HFJVSG [4.3 (1.3) kPa; P,0.01 compared with SHFJVSG]. Conclusion. SHFJVSG was associated with increased EEVCW and VT compared with the three other investigated JV modes. All four modes provided adequate ventilation and oxygenation, and thus can be used for uncomplicated laryngeal surgery in healthy patients with limited airway obstruction. 

Exercise improvement after pectus excavatum repair is not related to chest wall function

Acosta J., Bradley A., Raja V., Aliverti A., Badiyani S., Motta A., Moriconi S., Parker K., Rajesh P., Naidu B.


OBJECTIVES: In patients undergoing corrective surgery for pectus excavatum, there is evidence of improvement in cardiopulmonary function. It is unclear how much of this improvement is attributable to improved chest wall function. Thus, we observed changes in chest wall function in response to an incremental load exercise pre- and postoperatively. METHODS: Using optoelectronic plethysmography, total and regional chest wall volumes were measured in 7 male patients with severe pectus excavatum who underwent a Nuss correction. Rib cage and abdominal volumes were recorded at rest and during exercise (incremental cycle ergometry), pre- and postoperatively in conjunction with spirometry. RESULTS: Tidal volume increases during exercise are blunted compared with baseline measurements at 6 days (−36 ± 7%) partially recovering at 6 months postoperatively (−18 ± 22%). This is mirrored by changes in spirometry. Tidal volume decreased during exercise initially in all compartments, but persisted in the rib cage compartment. An increase of 44% (P = 0.009) in exercise tolerance was found 6 months after surgical correction. CONCLUSIONS: Six months after Nuss correction in pectus patients, there was a decrease in rib cage mobility. Despite reduction, patients had a significant improvement in exercise tolerance. Therefore, we conclude that early postoperative improvement in exercise capacity is not due to changes in chest wall function. The longer term effects on chest wall function are yet to be defined.

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