Background: The power of breathing (PoB) is used to estimate the mechanical workload of the respiratory system. Aim of this study was to investigate the effect of different tidal volume-respiratory rate combinations on the PoB when the elastic load is constant. In order to assure strict control of the experimental conditions, the PoB was calculated on an airway pressure-volume curve in mechanically ventilated patients.
Methods: Ten patients received three different tidal volume-respiratory rate combinations while minute ventilation was constant. Respiratory mechanics, PoB and its elastic and resistive components were calculated. Alternative methods to estimate the elastic workload were assessed: elastic work of breathing per litre per minute, elastic workload index (the square root of elastic work of breathing multiplied by respiratory rate) and elastic double product of the respiratory system (the elastic pressure multiplied by respiratory rate).
Results: Despite constant elastance and minute ventilation, the elastic PoB showed an increment greater than 200% from the lower to the greater tidal volume, accounting for approximately 80% of the whole PoB increment. On the contrary, elastic work of breathing per litre per minute, elastic workload index and elastic double product did not change.
Conclusion: Changes in breathing pattern markedly affect the PoB despite constant mechanical load. Other indexes could assess the elastic workload without tidal volume dependence. Power of breathing use should be avoided to compare different mechanical loads or efficiencies of the respiratory muscles when tidal volume is variable.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1111/j.1399-6576.2005.00664.x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Improving lung protective mechanical ventilation: the individualised intraoperative open-lung approach.
Br J Anaesth
February 2025
CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain; Intensive Care Unit, Hospital Universitario La Princesa, Madrid, Spain.
Despite the maturity and sophistication of anaesthesia workstations, improvements in our understanding of intraoperative mechanical ventilation, and use of less invasive surgical techniques, postoperative pulmonary complications (PPCs) are still a common problem in surgical patients of all ages. PPCs are associated with a higher incidence of perioperative morbidity and mortality, longer hospital stays, and higher healthcare costs. PPCs are strongly associated with anaesthesia-induced atelectasis, which predisposes to lung damage when partially collapsed lungs are subjected to mechanical ventilation.
View Article and Find Full Text PDFEnhanced breathing effort in pulmonary function tests by CO2/O2 gas mixture and barometric whole-body plethysmography in healthy and feline lower airway disease cats.
Am J Vet Res
January 2025
National Taiwan University Veterinary Hospital, National Taiwan University, Taipei, Taiwan.
Objective: Enhancing ventilatory effort during pulmonary function testing can help reveal flow limitations not evident in normal tidal breathing. This study aimed to assess the efficacy and tolerability of using a CO2/O2 gas mixture to enhance tidal breathing with a barometric whole-body plethysmography system in both healthy cats and those with feline lower airway disease (FLAD).
Methods: This prospective study included healthy cats and those with FLAD, which underwent pulmonary function testing and were exposed to a 10% CO2/90% O2 gas mixture in a barometric whole-body plethysmography chamber, with CO2 concentrations maintained within the target range of 5% to 10%.
Electrical impedance tomography confirmed the impact of the method of delivery of term neonates on early lung aeration.
Adv Clin Exp Med
January 2025
Clinic of Children's Diseases, Institute of Clinical Medicine, Faculty of Medicine, Vilnius University, Lithuania.
Background: The number of infants born via cesarean section (CS) is increasing globally due to medical and cultural reasons.
Objectives: This study aimed to determine the effect of the mode of delivery on early lung aeration in newborns using electrical impedance tomography (EIT).
Material And Methods: The case-control study was conducted from December 2020 to April 2021.
Automated mechanical ventilator design and analysis using neural network.
Sci Rep
January 2025
School of Computing, SASTRA Deemed University, Thanjavur, Tamil Nadu, India.
Mechanical ventilation is the process through which breathing support is provided to patients who face inconvenience during respiration. During the pandemic, many people were suffering from lung disorders, which elevated the demand for mechanical ventilators. The handling of mechanical ventilators is to be done under the assistance of trained professionals and demands the selection of ideal parameters.
View Article and Find Full Text PDFNitrosyl factors play a vital role in the ventilatory depressant effects of fentanyl in freely moving guinea pigs.
Biomed Pharmacother
January 2025
Department of Pediatrics, Case Western Reserve University, Cleveland, OH, USA; Department of Pharmacology, Case Western Reserve University, Cleveland, OH 44106, USA.
An understanding of intracellular mechanisms by which fentanyl and other synthetic opioids exert adverse effects on breathing is needed. Using freely moving adult male guinea pigs, we administered the nitric oxide synthase (NOS) inhibitor, L-NAME (N-nitro-L-arginine methyl ester), to determine whether nitrosyl factors, such as nitric oxide and S-nitrosothiols, play a role in fentanyl-induced respiratory depression. Ventilatory parameters were recorded by whole body plethysmography to determine the effects of fentanyl (75 μg/kg, IV) in guinea pigs that had received a prior injection of vehicle (saline), L-NAME or the inactive D-isomer, D-NAME (both at 50 μmol/kg, IV), 15 min beforehand.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!