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Background: Although Osteogenesis Imperfecta (OI) affects the connective tissue, pulmonary function might be compromised because of thoracic deformities. OI is known to be a restrictive lung disease, but spirometry provides global measurement without localizing the site of the restriction. Opto-electronic plethysmography (OEP), is a non-invasive method able to underline altered respiratory function as well as ventilatory thoraco-abdominal paradoxes during spontaneous breathing. We aimed to reconstruct the thoraco-abdominal surface, to perform local analyses of trunk motion and to make quantitative comparison of trunk shape and respiratory kinematics according to OI severity, particularly during maximal inspiratory and expiratory expansions. This is a cross-sectional study where we have studied the thoraco-abdominal compartmental analysis in 26 adult OI patients (14 Type III) at rest and during vital capacity manoeuvre using OEP. We have also applied a new method that created realistic and accurate 3D models to perform local analyses of trunk motion and to make quantitative comparison of trunk shape and respiratory kinematics.Results: Type III patients were characterized by lower spirometric lung volume, by lower sleep quality, by a more compressed thoracic configuration aggravated by severe scoliosis, by reduced global expansion at rest and during maximal maneuvers because of the reduced expansion of the pulmonary ribcage at rest (12% vs. 65% in healthy subjects), during maximal inspiration (37% vs. 69%) and expiration (16% vs. 68%) with local paradoxical movement occurring on the side of the ribcage region.Conclusion: The kinematics of the trunk changed to compensate for the severe structural deformities by shifting the expansion in the abdomen both at rest and during maximal manoeuvre because of a restricted thorax. For the first time, we have quantified and localized the site of the restriction in OI patients in the lateral part of the thorax. The 3D analysis proposed seemed a promising graphical immediate new method for pathophysiology study of chest wall restriction. [ABSTRACT FROM AUTHOR]

Background: Although Osteogenesis Imperfecta (OI) affects the connective tissue causing extremely brittle bones with consequent skeletal deformities, it is important to go beyond bones. Indeed, the quality of life in OI does not only depend on bones status, as OI might affect also other important functions. We have therefore implemented a multidisciplinary study to assess lung function, breathing pattern, sleep quality and nutritional status in 27 adult OI type III and IV patients (median age: 34.6 years; 19 women; 14 type III).Results: According to nocturnal oxygen desaturation, two groups were identified: 13 patients with (OI_OSA, incidence: 48.2%) and 14 without (no_OSA) obstructive sleep apnea. The former was characterized by higher spinal and ribcage deformity, by more restrictive lung function, by paradoxical thoracic breathing in supine position, by rapid and shallow breathing, by higher body mass index, by longer neck and waist circumferences; by higher abdominal volume and by greater percentage of body fat mass, particularly localized in the trunk. The best predictor of OI_OSA was the negative value of the supine ribcage contribution to tidal volume, followed by the ratio between the neck and the waist circumferences with body height and the supine thoraco-abdominal volumes phase shift angle.Conclusions: The pathophysiology of OI ensued a dangerous vicious circle, in which breathing, sleep and nutritional status are tightly linked, and they might all end up in negatively affecting the quality of life. The vicious circle is fed by some intrinsic characteristics of the disease (thoracic, cranial and mandibular deformities) and some bad daily habits of the patients (i.e. physical inactivity and low dietary quality). The former impacts on restricting the respiratory function, the latter makes Olers more prone to experience overweight or obesity. The main consequence is a high incidence of obstructive sleep apnea, which remains an underdiagnosed disorder in individuals with severe OI who are obese, with a neck to height ratio over than 31.6%, and characterized by paradoxical breathing in supine position. A multidisciplinary approach, including evaluations of breathing, sleep and nutrition, is required to better manage the disease and fulfil the maximizing well-being of OI patients. [ABSTRACT FROM AUTHOR]

• Apnea and HFJV at 300–400 Hz induce minimal surrogate marker movement. • Apnea and HFJV at 300–400 Hz induce hypercapnia. • Tidal volume of 80 ml observed with HFJV at 200 Hz results in effective CO 2 removal. • HFJV at 200 Hz is the best compromise between lung immobilization and gas exchange. • Abdominal motion is highly correlated to diaphragm motion. Respiratory-induced motion introduces uncertainties in the delivery of dose in radiotherapy treatments. Various methods are used clinically, e.g. breath-holding, while there is limited experience with other methods such as apneic oxygenation and high frequency jet ventilation (HFJV). This study aims to compare the latter approaches for lung immobilization and their clinical impact on gas exchange in an animal model. Two radiopaque tumor surrogate markers (TSM) were placed in the central (cTSM) and peripheral (dTSM) regions of the lungs in 9 anesthetized and muscle relaxed pigs undergoing 3 ventilatory interventions (1) HFJV at rates of 200 (JV200), 300 (JV300) and 400 (JV400) min−1; (2) apnea at continuous positive airway pressure (CPAP) levels of 0, 8 and 16 cmH 2 O; (3) conventional mechanical ventilation (CMV) as reference mode. cTSM and dTSM were visualized using fluoroscopy and their coordinates were computed. The ventilatory pattern was registered, and oxygen and carbon dioxide (pCO 2) partial pressures were measured. The highest range of TSM motion, and ventilation was found during CMV, the lowest during apnea. During HFJV the amount of motion varied inversely with increasing frequency. The reduction of TSM motion at JV300, JV400 and all CPAP levels came at the cost of increased pCO 2 , however the relatively low frequency of 200 min−1 for HFJV was the only ventilatory setting that enabled adequate CO 2 removal. In this model , HFJV at 200 min−1 was the best compromise between immobilization and gas exchange for sessions of 10-min duration. [ABSTRACT FROM AUTHOR]

Lung transplantation is a complex but effective treatment of end-stage pulmonary disease. Among the post-operative complications, phrenic nerve injury, and consequent diaphragmatic dysfunction are known to occur but are hitherto poorly described. We aimed to investigate the effect of lung transplantation on diaphragmatic function with a multimodal approach. A total of 30 patients were studied at 4 time points: pre-operatively, at discharge after surgery, and after approximately 6 and subsequently 12 months post surgery. The diaphragmatic function was studied in terms of geometry (assessed by the radius of the diaphragmatic curvature delineated on chest X-ray), weakness (considering changes in forced vital capacity when the patient shifted from upright to supine position), force (maximal pressure during sniff), mobility (excursion of the dome of the diaphragm delineated by ultrasound), contractility (thickening fraction assessed by ultrasound), electrical activity (latency and area of compound muscle action potential during electrical stimulation of phrenic nerve), and kinematics (relative contribution of the abdominal compartment to tidal volume). Despite good clinical recovery (indicated by spirometry and 6 minutes walking test), a reduction of the diaphragmatic function was detected at discharge; it persisted 6 months later to recover fully 1 year after transplantation. Diaphragmatic dysfunction was demonstrated in terms of force, weakness, electrical activity, and kinematics. Our data suggest that the dysfunction was caused by phrenic nerve neurapraxia or moderate axonotmesis, potentially as a consequence of the surgical procedure (i.e., the use of ice and pericardium manipulation). The occurrence of diaphragmatic dysfunction in patients with a good clinical recovery indicates that the evaluation of diaphragmatic function should be included in the post-operative assessment after lung transplantation. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The video-assisted thoracic surgery (VATS) approach is encouraged over postero-lateral thoracotomy (PLT) for lobectomy in lung cancer. We compare the ribcage kinematics during exercise before and after both procedures, assuming that VATS, being minimally invasive, could better preserve ribcage expansion. METHODS: Thirty-one patients undergoing lobectomy by means of VATS (n = 20) or PLT (n = 11) were compared presurgery, after chest drainage removal (T1) and 2 months post-surgery (T2) during quiet breathing and incremental exercise. Spirometry, chest pain, ventilatory pattern and expansions of the ribcage (ΔVRC) and abdomen were measured. Furthermore, the expansion of the ribcage and abdomen in the operated (ΔVRC-OP and ΔVAB-OP, respectively) and non-operated (ΔVRC-NO and ΔVAB-NO, respectively) sides was also considered. RESULTS: At T1, in both groups, spirometry worsened and chest pain increased, being higher after PLT. Tidal volume (VT) decreased after PLT because the ribcage expanded less due to reduced ΔVRC-OP. Contrary to this, in VATS, there were no changes in VT and ΔVRC, although ΔVRC-OP was lower, because ΔVRC-NO increased at high level of exercise. At T2, ΔVRC-OP was completely restored after VATS. At high levels of exercise following PLT, although patients still showed reduced ΔVRC and ΔVRC-OP, VT was restored owing to increased ΔVAB-NO. CONCLUSIONS: We demonstrate VATS to have a reduced impact on ribcage kinematics while PLT induced restriction more markedly during exercise and still present 2 months after surgery. Patients adopt 2 different compensatory mechanisms, by shifting the expansion toward the contralateral ribcage after VATS and toward the abdomen after PLT. Our study justifies thoracoscopic lobectomy prompt recovery. [ABSTRACT FROM AUTHOR]

It is not completely described how aging affect ventilatory kinematics and what are the mechanisms adopted by the elderly population to overcome these structural modifications. Given this, the aim was to evaluate the acute effects of different inspiratory efforts on ventilatory pattern and chest wall compartmental distribution in elderly women. Variables assessed included: tidal volume (Vt), total chest wall volume (Vcw), pulmonary rib cage (Vrcp%), abdominal rib cage (Vrca%) and abdominal compartment (Vab%) relative contributions to tidal volume. These variables were assessed during quiet breathing, maximal inspiratory pressure maneuver (MIP), and moderate inspiratory resistance (MIR; i.e., 40% of MIP). 22 young women (age: 23.9 ± 2.5 years) and 22 elderly women (age: 68.2 ± 5.0 years) participated to this study. It was possible to show that during quiet breathing, Vab% was predominant in elderly ( p < 0.001), in young, however, Vab% was similar to Vrcp% ( p = 0.095). During MIR, Vrcp% was predominant in young ( p < 0.001) and comparable to Vab% in elderly ( p = 0.249). When MIP was imposed, both groups presented a predominance of Vrcp%. In conclusion, there are differences in abdominal kinematics between young and elderly women during different inspiratory efforts. In elderly, during moderate inspiratory resistance, the pattern is beneficial, deep, and slow. Although, during maximal inspiratory resistance, the ventilatory pattern seems to predict imminent muscle fatigue. [ABSTRACT FROM AUTHOR]

Highlights: [•] In SMA motor neurons degenerate and determine muscle wasting and weakness. [•] In SMA II and IIIA, intercostal muscles are weakened and the diaphragm is spared. [•] In SMA II and IIIA, diaphragm leads inspiration with possible thoracic inwarding. [•] In SMA IIIB all inspiratory muscles are preserved. [•] SMA III sub-classification is valid both for motor and respiratory function. [ABSTRACT FROM AUTHOR]

Highlights: [•] We evaluated obese women during quiet breathing. [•] The chest wall volumes and breathing patterns were assessed. [•] Obese women were characterized by lung restriction and higher minute ventilation at rest. [•] Volume variations of the pulmonary rib cage are lower and volume variations of the abdomen are higher in obese women. [•] The kind of obesity, either central or peripheral, does not further influence lung function and thoraco-abdominal pattern. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the effects of posture and gender on thoraco-abdominal motion and breathing pattern, 34 healthy men and women were studied by Opto-Electronic Plethysmography during quiet breathing in five different postures from seated (with and without back support) to supine position. Chest wall kinematics and breathing pattern were significantly influenced by position and gender. The progressively increased inclination of the trunk determined a progressive reduction of rib cage displacement, tidal volume, and minute ventilation and a progressive increase of abdominal contribution to tidal volume. Female subjects were characterized by smaller dimensions of the rib cage compartment and during quiet breathing by lower tidal volume, minute ventilation and abdominal contribution to tidal volume than males. The effect of posture on abdominal kinematics was significant only in women. The presence of a back support in seated position determined differences in breathing pattern. In conclusion, posture and gender have a strong influence on breathing and on chest wall kinematics. [Copyright &y& Elsevier]

Abstract: Breath-by-breath (BbB) oxygen uptake rate was measured at the mouth (MO) and at the alveolar level, at the onset of square wave cycling exercise of moderate intensity in six healthy male subjects. Alveolar BbB values were calculated correcting MO values by (i) estimating (GR); and (ii) measuring (opto-electronic plethysmography, OEP) BbB lung O2 store changes. kinetics was then described by a bi-exponential model. GR yielded larger values of the time constants (τ 2) of the primary phase of kinetics. The mean response times (MRTs) calculated by analysing GR BbB values were larger than (i) those obtained by using MO and OEP at 90W; and (ii) that by using MO at 120W. OEP corrected yielded the highest normalised amplitude of the cardiodynamic phase of the on-response. Correction of BbB for actual BbB changes of lung O2 stores by OEP thus seems more appropriate for the study of the early cardiodynamic phase of kinetics than GR. [Copyright &y& Elsevier]

Keywords: Sternal angle; opto-electronic plethysmography; Euler angles EN Sternal angle opto-electronic plethysmography Euler angles S411 S412 2 01/29/21 20191002 NES 191002 1. Cross product is used to generate two direct orthonormal vector fields: (Graph HT ht Graph HT ht Graph HT ht ) attached to the manubrium orientation in space and (Graph HT ht Graph HT ht Graph HT ht ) attached to the sternum orientation in space. [Extracted from the article]