Search results for "ventilator"
showing 10 items of 84 documents
Patient-Ventilator Asynchronies: Clinical Implications and Practical Solutions
2020
Mechanical ventilation is a supportive treatment commonly applied in critically ill patients. Whenever the patient is spontaneously breathing, the pressure applied to the respiratory system depends on the sum of the pressure generated by the respiratory muscles and the pressure generated by the ventilator. Patient-ventilator interaction is of utmost importance in spontaneously breathing patients, and thus the ventilator should be able to adapt to patient's changes in ventilatory demand and respiratory mechanics. Nevertheless, a lack of coordination between patient and ventilator due to a mismatch between neural and ventilator timing throughout the respiratory cycle may make weaning difficul…
Ventilator Settings to Avoid Nuisance Alarms During Mouthpiece Ventilation
2016
BACKGROUND: A recent study found that activation of disconnection and low-pressure alarms is common during mouthpiece ventilation and may represent a major limitation to its use. The aim of this bench study was: (1) to investigate the technical aspects that can influence the setting of the ventilator during mouthpiece ventilation and (2) to provide a practical setting strategy to avoid the alarm activation. METHODS: Eight life-support ventilators able to deliver volume controlled ventilation were tested in a bench study using a single-limb non-vented circuit configuration connected to a standard mouthpiece. Disconnection and apnea alarm were turned off or set at the least sensitive setting.…
Blockade of astrocytic activation delays the occurrence of severe hypoxia-induced seizure and respiratory arrest in mice
2020
Seizures are induced when subjects are exposed to severe hypoxia. It is followed by ventilatory fall-off and eventual respiratory arrest, which may underlie the pathophysiology of death in patients with epilepsy and severe respiratory disorders. However, the mechanisms of hypoxia-induced seizures have not been fully understood. Because astrocytes are involved in various neurological disorders, we aimed to investigate whether astrocytes are operational in seizure generation and respiratory arrest in a severe hypoxic condition. We examined the effects of astrocytic activation blockade on responses of EEG and ventilation to severe hypoxia. Adult mice were divided into two groups; in one group …
Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): study protocol for a randomized controlled trial.
2012
Abstract Background Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with …
Analysis of discrete and continuous distributions of ventilatory time constants from dynamic computed tomography.
2005
In this study, an algorithm was developed to measure the distribution of pulmonary time constants (TCs) from dynamic computed tomography (CT) data sets during a sudden airway pressure step up. Simulations with synthetic data were performed to test the methodology as well as the influence of experimental noise. Furthermore the algorithm was applied to in vivo data. In five pigs sudden changes in airway pressure were imposed during dynamic CT acquisition in healthy lungs and in a saline lavage ARDS model. The fractional gas content in the imaged slice (FGC) was calculated by density measurements for each CT image. Temporal variations of the FGC were analysed assuming a model with a continuous…
Ventilation, oxidative stress and risk of brain injury in preterm newborn
2020
AbstractPreterm infants have an increased risk of cognitive and behavioral deficits and cerebral palsy compared to term born babies. Especially before 32 weeks of gestation, infants may require respiratory support, but at the same time, ventilation is known to induce oxidative stress, increasing the risk of brain injury. Ventilation may cause brain damage through two pathways: localized cerebral inflammatory response and hemodynamic instability. During ventilation, the most important causes of pro-inflammatory cytokine release are oxygen toxicity, barotrauma and volutrauma. The purpose of this review was to analyze the mechanism of ventilation-induced lung injury (VILI) and the relationship…
Mechanical ventilation in patients with cardiogenic pulmonary edema: a sub-analysis of the LUNG SAFE study
2022
Supported by Centro de Investigación Biomédica en Red (CIBER)‑Enfermedades respiratorias, Madrid, Spain (CB17/06/00021) and Fundación para el Fomento en Asturias de la Investigación Científica aplicada y la tecnología (FICYT, AYUD2021/52014). RRG is the recipient of a grant from Instituto de Salud Carlos III, Madrid, Spain (CM20/00083).
Ventilatory chemosensitivity, cerebral and muscle oxygenation, and total hemoglobin mass before and after a 72-day mt. Everest expedition.
2014
Abstract. Cheung, Stephen S, Niina E. Mutanen, Heikki M. Karinen, Anne S. Koponen, Heikki Kyro ̈ la ̈ inen, Heikki O. Tikkanen, and Juha E. Peltonen. Ventilatory chemosensitivity, cerebral and muscle oxygenation, and total hemoglobin mass before and after a 72-day Mt. Everest expedition. High Alt Med Biol 15:331–340, 2014.— Background: We investigated the effects of chronic hypobaric hypoxic acclimatization, performed over the course of a 72-day self-supported Everest expedition, on ventilatory chemosensitivity, arterial saturation, and tissue oxygenation adaptation along with total hemoglobin mass (tHb-mass) in nine experienced climbers (age 37 – 6 years, _ VO 2peak 55 – 7mL $ kg - 1 $ min…
Antioxidation and the Hypoxic Ventilatory Response
2012
Reactive oxygen species favor the reductive state of iron. Antioxidation, by depleting biologically active ferrous iron, could then have a stabilizing effect, akin to hypoxia, on HIF-1α; the process which controls the genetic responses to hypoxia. However, the influence of antioxidation on the hypoxic ventilatory responses (HVR) is unclear. In this study we set out to determine the influence of mangiferin, a natural polyphenolic compound present in mango trees, with strong antioxidant and iron chelating properties, on the HVR. The study was performed in awake Wistar rats. Acute HVR to 12% and 8% FiO2 before and 40 min after mangiferin (300 mg/kg, i.p.) pretreatment were recorded plethysmogr…
Deguna un plaušu ventilācijas funkciju salīdzinājums pacientiem pirms deguna ķirurģijas
2020
Ir pierādīta augšējo un dziļo elpceļu vienotība alerģisku slimību kontekstā, taču apgrūtinātas deguna elpošanas ietekme uz elpceļiem ārpus tā joprojām nav pilnībā izpētīta, un ir nepieciešama dziļāka izpratne par elpceļu daļu mijiedarbības rezultātiem. Darba mērķis ir salīdzināt deguna un plaušu funkcionālos rādītājus pacientiem ar apgrūtinātu deguna elpošanu, kam plānota deguna ķirurģija, kā arī salīdzināt spirometrijas rādītājus apgrūtinātas un brīvas deguna elpošanas grupās. Materiāli un metodes: Tika veikts gadījuma-kontroles pētījums klīnikā „Headline”, izmantojot četru fāžu rinomanometriju (4PR) pētījuma grupai (24 pacienti ar deguna obstrukciju, kam plānota deguna ķirurģija), un spir…