Stiffness of the pleural surface of the chest wall is similar to that of the lung

2003 ◽  
Vol 95 (6) ◽  
pp. 2345-2349 ◽  
Author(s):  
Andrew Gouldstone ◽  
Richard E. Brown ◽  
James P. Butler ◽  
Stephen H. Loring
Keyword(s):  
Chest Wall ◽  
Elastohydrodynamic Lubrication ◽  
Geometric Standard Deviation ◽  
Parietal Pleura ◽  
Shear Stresses ◽  
Membrane Tension ◽  
Similar Extent ◽  
Spatial Uniformity ◽  
Pleural Surface

To address the role of the parietal pleura in reduction of mesothelial shear stresses during breathing, we measured the stiffness of the parietal pleural surface of mammalian chest walls using microindentation. The pleural surface was indented over ribs and intercostal spaces with rigid flat punches (tip radii of 0.01, 0.02, and 0.1 cm) to probe stiffness at length scales comparable with those of surface asperities. We found a tissue shear modulus of 6,700 dyn/cm2 and pleural membrane tension of 4,900 dyn/cm, with a geometric standard deviation of 0.42. These values are similar to those measured for the lung by Hajji et al., using indentation (Hajji MA, Wilson TA, and Lai-Fook SJ. J Appl Physiol Respirat Environ Exerc Physiol 47: 175–181, 1979). Surprisingly, the pleural surface over ribs and intercostal spaces exhibited similar stiffness. In addition, caudal regions exhibited lower stiffness than cranial regions. In the context of elastohydrodynamic lubrication, these results suggest that shear-induced pressures during breathing deform the chest wall and lung surfaces to a similar extent, promoting spatial uniformity of pleural fluid thickness and reducing shear stresses.

Pleural stress pressure as a force to control liquid accumulation and maintain lung expansion

1985 ◽  
Vol 58 (2) ◽  
pp. 339-345 ◽  
Author(s):  
K. Harada ◽  
T. Mutsuda ◽  
N. Saoyama ◽  
N. Hamaguchi ◽  
Y. Shimada
Keyword(s):  
Chest Wall ◽  
Mean Value ◽  
Pleural Space ◽  
Liquid Volume ◽  
Parietal Pleura ◽  
Elastic Recoil ◽  
Normal Range ◽  
Pleural Surface ◽  
Lung Expansion ◽  
The Relationship

Total gas pressure in the pleural space is more subatmospheric than that in the alveolar cavity. This pressure difference minus elastic recoil pressure of the lung was termed stress pressure. We investigated the relationship between stress pressure and a force that would hold the lung against the chest wall to prevent accumulation of liquid. The condition was a pleural space with an enlarged pleural surface pressure. Dogs anesthetized with pentobarbital sodium were placed in a box maintained subatmospherically at approximately -30 cmH2O and breathed atmospheric air for 4 h. Liquid volume in the pleural space of the dogs was measured under conditions of thoracotomy. In the normal group, the volume of the pleural liquid was within the normal range of approximately 2.0 ml and the visceral and the parietal pleura made contact. In the pneumothorax group, established by injecting 50 ml of air into the pleural space, the liquid increased significantly in all cases by a mean value of approximately 12 ml. Thus pleural stress pressure seems to be an important force holding the lung against the chest wall and aiding in the control of accumulation of liquid in a more subatmospheric pleural space.

Shear stress alters pleural mesothelial cell permeability in culture

1996 ◽  
Vol 81 (1) ◽  
pp. 448-458 ◽  
Author(s):  
C. M. Waters ◽  
M. R. Glucksberg ◽  
N. Depaola ◽  
J. Chang ◽  
J. B. Grotberg
Keyword(s):  
Shear Stress ◽  
Chest Wall ◽  
Fluid Shear Stress ◽  
Mesothelial Cells ◽  
Pleural Space ◽  
Cell Permeability ◽  
Parietal Pleura ◽  
Sodium Fluorescein ◽  
Shear Stresses ◽  
Visceral Pleura

The sliding motion of the lung against the chest wall creates a shear stress in the pleural space, which can be as high as 60 dyn/cm2, depending on the respiration rate. Such shear stresses may affect the mesothelial cells that line the pleural space on the lung (visceral pleura) and chest wall (parietal pleura). When exposed to shear stress (17 dyn/cm2) in a parallel-plate flow chamber for 22 h, rat visceral pleura mesothelial cells were not altered morphologically and did not align in the direction of flow, in contrast to the shape changes observed for bovine aortic endothelial cells. By using mesothelial cells cultured on porous microcarrier beads, we measured the permeability of the cells at different flows in a cell-column chromatography assay. The permeabilities to sodium fluorescein and cyanocobalamin increased from 8.2 +/- 1.0 and 7.8 +/- 0.7 x 10(-5) cm/s to 22.5 +/- 1.2 and 21.8 +/- 3.0 x 10(-5) cm/s, respectively, when the flow was increased from 0.9 to 3.5 ml/min (corresponding to average shear stresses of 4.7-18.4 dyn/cm2). The permeabilities returned to baseline values when the flow was reduced. Cytochalasin D stimulated an increase in permeability that was not augmented by a subsequent increase in shear stress. These results suggest that the barrier function of mesothelial cells is responsive to changes in fluid shear stress.

scholarly journals Preoperative computed tomography-guided localization of lung nodules with needle placement: a series of cases

2021 ◽  
Vol 48 ◽  
Author(s):  
RAFAEL EGOROFF FOGOLIN ◽  
PAULO CESAR BUFFARA BOSCARDIM ◽  
JULIANO MENDES SOUZA
Keyword(s):  
Computed Tomography ◽  
Chest Wall ◽  
Surgical Intervention ◽  
Pulmonary Nodules ◽  
Lung Nodules ◽  
Histopathological Study ◽  
Parietal Pleura ◽  
Needle Placement ◽  
Pleural Surface ◽  
Shortest Distance

ABSTRACT Objective: to report the preoperative localization of pulmonary nodules with the placement of a guidewire oriented by Computed Tomography. Methods: the nodules were marked using a needle in the shape of a hook or another in the shape of a Q, guided by tomography. The choice of the location for the marking was the shortest distance from the chest wall to the nodule. The marking procedure was performed under local anesthesia and a tomographic control was obtained immediately at the end. Patients were referred to the operating room. Surgical resection occurred less than two hours after the needle placement. Results: between February 2017 and October 2019, 22 patients aged 43 to 82 years (mean 62.1) were included. The nodules had diameters that varied from 4 to 30 mm and the distance between the nodules and the pleural surface varied from 2 to 43 mm. The location and resection of the nodules were successfully performed in all cases. The guidewire was displaced in five cases. Five patients presented pneumothorax, with the space between the visceral and parietal pleura varying from 2 to 19 mm. In nine patients, an intraparenchymal hematoma of 6 to 35 mm in length was observed without signs, symptoms, or hemodynamic and ventilatory repercussions. The histopathological study was conclusive in all patients. Conclusions: the localization of pulmonary nodules through guidewires proved to be safe, reliable, and feasible in this series of cases. There was no need for surgical intervention to treat complications.

Quantitative Analysis of Reynolds and Navier–Stokes Based Modeling Approaches for Isothermal Newtonian Elastohydrodynamic Lubrication

2021 ◽  
Vol 143 (12) ◽  
Author(s):  
Leoluca Scurria ◽  
Tommaso Tamarozzi ◽  
Oleg Voronkov ◽  
Dieter Fauconnier
Keyword(s):  
High Speed ◽  
Stokes Equations ◽  
Thickness Distribution ◽  
Elastohydrodynamic Lubrication ◽  
Lubricant Film ◽  
Secondary Flows ◽  
Navier Stokes ◽  
Shear Stresses ◽  
Low Viscosity ◽  
Fluid Film Thickness

Abstract When simulating elastohydrodynamic lubrication, two main approaches are usually followed to predict the pressure and fluid film thickness distribution throughout the contact. The conventional approach relies on the Reynolds equation to describe the thin lubricant film, which is coupled to a Boussinesq description of the linear elastic deformation of the solids. A more accurate, yet a time-consuming method is the use of computational fluid dynamics in which the Navier–Stokes equations describe the flow of the thin lubricant film, coupled to a finite element solver for the description of the local contact deformation. This investigation aims at assessing both methods for different lubrication conditions in different elastohydrodynamic lubrication (EHL) regimes and quantify their differences to understand advantages and limitations of both methods. This investigation shows how the results from both approaches deviate for three scenarios: (1) inertial contributions (Re > 1), i.e., thick films, high speed, and low viscosity; (2) high shear stresses leading to secondary flows; and (3) large deformations of the solids leading to inaccuracies of the Boussinesq equation.

scholarly journals Clinical Implications High Frequency Chest Wall Oscillation (HFCWO)

2012 ◽  
Vol 1 (1) ◽  
Author(s):  
E. Mantellini ◽  
L. Perrero ◽  
S. Petrozzino ◽  
A. Gatta ◽  
S. Bona
Keyword(s):  
Chest Wall ◽  
High Frequency ◽  
Neuromuscular Disease ◽  
Respiratory Infections ◽  
Neuromuscular Diseases ◽  
Correct Treatment ◽  
Bronchial Secretions ◽  
High Incidence ◽  
Wall Oscillation

Purpose: patients with neuromuscular diseases presents an high incidence of respiratory infections favoured by stagnation of deep bronchial secretions and deficit of cough. The aim of the study is to evaluate the correct treatment of this condition and the role of High Frequency Chest Wall Oscillation (HFCWO) in helping the removal of bronchial secretions and reduce the incidence of infections in patients with neuromuscular disease. Methods: analysis of the current bibliography related to respiratory infections and neuromuscular disease. PCEF (Peak Cough Expiratory Flow) is used as a standardized indicator of efficiency of cough. Results: the High Frequency Chest Wall Oscillation (HFCWO) is useful, in cases of increased production of mucus and impairment of muco-ciliary clearance, to remove the tracheobronchial secretions and reduce the incidence of infections. Conclusions: the correct approach to patients with neuromuscular disease and frequent respiratory infections is focused on treatment of cough ineffective and management of bronchial secretions. High Frequency Chest Wall Oscillation (HFCWO) (VEST) has a central role in treatment of cough ineffective and management of bronchial secretions reducing respiratory infections.

scholarly journals Empyema Necessitans in the Setting of Methicillin-Susceptible Staphylococcus aureus Causing Pneumonia and Bacteremia

2018 ◽  
Vol 2018 ◽  
pp. 1-5
Author(s):  
Sindhura Bandaru ◽  
Sukesh Manthri ◽  
Vidya Sundareshan ◽  
Vidhya Prakash
Keyword(s):  
Staphylococcus Aureus ◽  
Chest Wall ◽  
Subcutaneous Tissue ◽  
Parietal Pleura ◽  
Intravenous Drug Use ◽  
Rare Occurrence ◽  
Left Forearm ◽  
Gram Stain ◽  
Incision And Drainage ◽  
Prompt Diagnosis

Empyema necessitans (EN) is a rare phenomenon that refers to an insidious extension of the empyema through parietal pleura and subsequent dissection into subcutaneous tissue of the chest wall. A 29-year-old man presented to the hospital with fever and chills a few days after an inadvertent needle stick while injecting heroin. His left forearm was warm with an area of fluctuance. He underwent incision and drainage of the left forearm abscess with fluid submitted for Gram stain and culture. His condition rapidly deteriorated due to sepsis, and he required transfer to the intensive care unit. A new 4 × 3 cm area over the left pectoralis muscle had become increasingly indurated, fluctuant, and erythematous. CT of the chest demonstrated extensive cavitary lung lesions and a large loculated left-sided pleural effusion with extension through the chest wall. TEE revealed a 3 cm complex lesion on the superior septal leaflet of the tricuspid valve. The patient underwent incision and drainage of the pectoralis major EN with placement of a drain. Blood and sputum cultures grew methicillin-susceptible Staphylococcus aureus (MSSA) at which time antibiotic therapy was tailored to oxacillin. Our case highlights a rare occurrence of EN due to MSSA in a patient with intravenous drug use (IDU) and underscores the importance of prompt diagnosis and treatment.

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