Search results for "ventilation"
showing 10 items of 476 documents
Industrial waste heat: Estimation of the technically available resource in the EU per industrial sector, temperature level and country
2018
Abstract Industrial waste heat is examined in EU countries, focusing on the amount that can be recovered and exploited, referred to as technical potential of waste heat. An alternative methodology is proposed here, which is based on waste heat fractions derived from a detailed study of the UK industry from the period 2000–2003. These fractions express the part of heat consumption that is wasted and is possible to be recovered. The waste heat fractions have been calculated in this work for each main industrial sector and temperature level. The methodology initially includes the adjustment of waste heat fractions from each industrial sector from the UK industry to the conditions of the differ…
Measurements of alveolar pO2 using 19F-MRI in partial liquid ventilation.
2003
Rationale and Objectives: Partial liquid ventilation using Perfluorcarbon (PFC) is an innovative treatment of acute respiratory distress syndrome. However, the underlying mechanisms are not totally clear. The aim was to investigate the distribution of oxygen partial pressure within the PFC-filled lung (ppO 2 ). Methods: Nine pigs underwent partial liquid ventilation, receiving 20 mL PFC/kg bodyweight (bw). Measurements were obtained by a chemical shift selective TurboFLASH sequence at different axial lung levels. ppO 2 was calculated from 1 9 F-MRI by nonlinear curve T 1 -fitting technique after noise correction. Results: Quantification and distribution of ppO 2 was performed successfully. …
Survey of neonatal respiratory support use in very preterm infants in Italy
2012
Background: Respiratory support in very preterm infants is often a life-saving procedure and several techniques are available. There is lack of data on the current use of these techniques. Methods and aim: We analyzed a cohort of infants <30 weeks gestation or < 1501 g birth weight, enrolled in the Italian Neonatal Network in 2009 and 2010 (n = 8297, mean gestation = 29.3 weeks, mean birth weight = 1089 g) to ascertain the use of several techniques. We also conducted a questionnaire survey of all neonatal units adhering to the Italian Neonatal Network, inquiring about preferred methods of respiratory support. Results: Conventional ventilation was used in 53% of these infants, high frequency…
Functional MR imaging of pulmonary ventilation using hyperpolarized noble gases.
2000
The current status of experimental and clinical applications for functional MR imaging of pulmonary ventilation using hyperpolarized noble gases are reviewed. 3-helium (3He) and 129-xenon (129Xe) can be hyperpolarized by optical pumping techniques such as spin exchange or metastability exchange in sufficient amounts. This process leads to an artificial, non-equilibrium increase of the density of excited nuclei which represents the source of the MR signal. Those hyperpolarized gases are administered mostly via inhalation, and will fill airways and airspaces allowing for ventilation imaging. Recent human studies concentrate on imaging the airways and airspaces with high spatial resolution. N…
Bi-Level ventilation decreases pulmonary shunt and modulates neuroinflammation in a cardiopulmonary resuscitation model
2020
Background Optimal ventilation strategies during cardiopulmonary resuscitation are still heavily debated and poorly understood. So far, no convincing evidence could be presented in favour of outcome relevance and necessity of specific ventilation patterns. In recent years, alternative models to the guideline-based intermittent positive pressure ventilation (IPPV) have been proposed. In this randomized controlled trial, we evaluated a bi-level ventilation approach in a porcine model to assess possible physiological advantages for the pulmonary system as well as resulting changes in neuroinflammation compared to standard measures. Methods Sixteen male German landrace pigs were anesthetized a…
Nasal provocation testing as an international standard for evaluation of allergic and nonallergic rhinitis.
2005
Standardized nasal provocation testing (NPT) has been shown to be a safe and very useful tool in the diagnosis of allergic and nonallergic rhinitis. However, in the United States, its use has been mostly limited to scientific investigations, and it has not yet been widely accepted as a standard diagnostic procedure in clinical practice. NPT aims to identify and quantify the clinical relevance of inhalant allergens or occupational irritants. During NPT, nasal respiratory mucosa is exposed to an airborne substance suspected to cause symptoms in the respective individual. Clinical reactions are monitored in a controlled and standardized fashion. Nasal secretions, symptoms such as itching, snee…
The new agreement of the international RIGA consensus conference on nasal airway function tests.
2018
The report reflects an agreement based on the consensus conference of the International Standardization Committee on the Objective Assessment of the Nasal Airway in Riga, 2nd Nov. 2016. The aim of the conference was to address the existing nasal airway function tests and to take into account physical, mathematical and technical correctness as a base of international standardization as well as the requirements of the Council Directive 93/42/EEC of 14 June 1993 concerning medical devices. Rhinomanometry, acoustic rhinometry, peak nasal inspiratory flow, Odiosoft-Rhino, optical rhinometry, 24-h measurements, computational fluid dynamics, nasometry and the mirrow test were evaluated for importa…
Bayesian joint modeling of bivariate longitudinal and competing risks data: An application to study patient-ventilator asynchronies in critical care …
2017
Mechanical ventilation is a common procedure of life support in intensive care. Patient-ventilator asynchronies (PVAs) occur when the timing of the ventilator cycle is not simultaneous with the timing of the patient respiratory cycle. The association between severity markers and the events death or alive discharge has been acknowledged before, however, little is known about the addition of PVAs data to the analyses. We used an index of asynchronies (AI) to measure PVAs and the SOFA (sequential organ failure assessment) score to assess overall severity. To investigate the added value of including the AI, we propose a Bayesian joint model of bivariate longitudinal and competing risks data. Th…
Nasal pressure swings as the measure of inspiratory effort in spontaneously breathing patients with de novo acute respiratory failure.
2022
Abstract Background Excessive inspiratory effort could translate into self-inflicted lung injury, thus worsening clinical outcomes of spontaneously breathing patients with acute respiratory failure (ARF). Although esophageal manometry is a reliable method to estimate the magnitude of inspiratory effort, procedural issues significantly limit its use in daily clinical practice. The aim of this study is to describe the correlation between esophageal pressure swings (ΔPes) and nasal (ΔPnos) as a potential measure of inspiratory effort in spontaneously breathing patients with de novo ARF. Methods From January 1, 2021, to September 1, 2021, 61 consecutive patients with ARF (83.6% related to COVID…
Ventilation rates and unsatisfied percentage from indoor CO2 concentration.
2011
This work reports the results of a survey carried out on a hall in a historic building in Palermo (Italy) with the aim of assessing the air quality by means of objective measurement of carbon dioxide (CO2) concentration and its subjective evaluation through a questionnaire. The measured values of CO2 concentration were compared with those evaluated using the Meckler equation under steady-state conditions, having verified necessary parameters such as the constancy of the indoor and outdoor CO2 levels and the uniformity of the CO2 generation rate for all the occupants. The positive correspondence between measured and calculated results allowed us to utilise, under differing circum- stances, t…