Teaching the distribution of pulmonary blood flow using a Starling resistor model and turbine flowmeters.

The distribution of pulmonary blood flow is uneven and can be described as a three-zone model, the West zones: zone 1 occurs whenever alveolar pressure exceeds arterial pressure; zone 2 when the arterial pressure is greater than alveolar but the alveolar pressure exceeds the venous pressure; and finally zone 3 when both arterial and venous pressures exceed alveolar pressure. Consequently, the blood flow is almost determined by the difference between the arterial and venous pressures in zone 3 and between arterial and alveolar pressures in zone 2 and ceases in zone 1. The understanding of this subject may be difficult to some medical students.

Innovative Pre-Clinical Data Using Peptides to Intervene in the Evolution of Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a progressive, relentless, and deadly disease. Little is known about its pathogenetic mechanisms; therefore, developing efficient pharmacological therapies is challenging. This work aimed to apply a therapeutic alternative using immunomodulatory peptides in a chronic pulmonary fibrosis murine model.

Effectiveness of a 3D bikefitting method in riding pain, fatigue, and comfort: a randomized controlled clinical trial.

To investigate the effects of bike fitting compared to qualitative-based riding posture recommendations on comfort, fatigue, and pain in amateur cyclists. This was a randomised controlled parallel trial of 162 amateur cyclists divided into two groups: bike fitting group (BFG) - participants received a bike fitting session based on 3D kinematic assessments; and a control group (QG) - participants who received a handout containing qualitative-based cycling posture recommendations. Primary outcomes were perceived comfort (FEEL Scale), perceived fatigue (OMNI Scale), and perceived pain (numeric rating pain scale, NRPS).

Long-Term Effects of a Kinematic Bikefitting Method on Pain, Comfort, and Fatigue: A Prospective Cohort Study.

The purpose of this study is to analyze the long-term riders' subjective responses to a standardized bikefitting method on their bicycles. Eighty-six amateur mountain bikers had their riding posture and bicycle components ergonomically adjusted through a 3D kinematic bikefitting method. Validated subjective scales (Feeling, OMNI, and Numerical Rating Pain Scale) were used to assess their overall riding comfort and fatigue along with localized pain for six body parts.

Fish Oil Nanoemulsion Supplementation Attenuates Bleomycin-Induced Pulmonary Fibrosis BALB/c Mice.

Diets rich in omega-3 or -6 fatty acids will produce different profiles for cell membranes phospholipid constitutions. Omegas 3 and 6 are part of the diet and can modulate the inflammatory profile. We evaluated the effects of the oral absorption of fish oil, when associated with a lipid nanoemulsion in an experimental pulmonary inflammatory model.

Local envenomation caused by a bioactive peptide fraction of Bothrops jararaca snake venom induces leukocyte influx in the lung and changes in pulmonary mechanics.

The crude venom of the Bothrops jararaca snake (Bj-CV) is a complex mixture of biologically active proteins that includes a variety of peptides in the low molecular weight fraction (Bj-PF). We investigated how an intramuscular injection of Bj-CV (1.2 mg kg) and Bj-PF (0.

Combined exercise training improved exercise capacity and lung inflammation in rats with hepatopulmonary syndrome.

Aim: Physical exercise training attenuates pulmonary inflammation, but its effects on impaired respiratory function caused by hepatopulmonary syndrome (HPS) have not been evaluated. We determined if the combination of moderate intensity aerobic and resistance training during HPS development modifies exercise capacity, respiratory system mechanics, and lung inflammation responses.

Main Methods: Wistar rats were randomly divided into sham, HPS, and HPS + combined exercise training groups.

Right ventricular contractility decreases during exercise in patients with non-advanced idiopathic pulmonary fibrosis.

Early right ventricular dysfunction in patients with non-advanced idiopathic pulmonary fibrosis (IPF) has not been fully elucidated. Thus, we aimed to assess right ventricular functions in IPF patients and controls by speckle-tracking strain echocardiography at rest and peak exercise.We screened 116 IPF patients from February to August 2019 to include 20 patients with no history of oxygen therapy, peripheral saturation levels ≥92% at rest, Gender-Age-Physiology Index score ≤5, and modified Medical Research Council score ≤3.

Concentric and eccentric isokinetic hamstring injury risk among 582 professional elite soccer players: a 10-years retrospective cohort study.

Background/aim: Different authors have tried to correlate the peak isokinetic torque values with the incidence of soccer match injuries. However, due to the wide variety of assessment testing protocols, such an inference becomes difficult. This study aimed to verify the capacity of an isokinetic test to establish injury risk reference values for hamstring strain injuries.

Noninvasive assessment of peripheral skeletal muscle weakness in idiopathic pulmonary fibrosis: a pilot study with multiparametric MRI of the rectus femoris muscle.

Background: To investigate differences in magnetic resonance imaging (MRI) features of rectus femoris muscle between idiopathic pulmonary fibrosis (IPF) patients and healthy volunteers.

Methods: Thirteen IPF patients with GAP Index stage II disease were subjected to pulmonary function tests, 6-minute walk test (6MWT), quadriceps femoris muscle strength measurement and MRI of the thigh at rest. At MRI, muscle cross-sectional areas, T2 and T2* relaxometry, and 3-point Dixon fat fraction were measured.

Right ventricular dysfunction in patients with non-severe idiopathic pulmonary fibrosis: a cross-sectional prospective single-center study.

Background: Little is known about right ventricular dysfunction in non-advanced idiopathic pulmonary fibrosis (IPF) patients without hypoxemia at rest. We evaluated it at rest and during exercise.

Research Design And Methods: 123 IPF patients were evaluated, and 27 met all the following criteria: Gender-Age-Physiology Index score ≤5, modified Medical Research Council dyspnea score ≤3, peripheral oxygen saturation ≥92% at rest, and no history of oxygen therapy.

Lung MRI to predict response or lack of response to treatment in interstitial lung disease: initial observations on SSFSE/PROPELLER T2 match/mismatch.

Background: Ground-glass opacities (GGO) are frequently found in interstitial lung diseases (ILD) and may represent either active inflammation or subresolution interstitial fibrosis. We sought to investigate the ability of lung MRI to predict treatment response in individuals with ILD presenting with predominant GGO. : prospective cohort, 15 participants presenting with ILD manifested as predominant GGO and referred for a new treatment regimen with a systemic glucocorticoid and/or an immunosuppressive agent, underwent 1.

Brazilian Guidelines for Early Mobilization in Intensive Care Unit.

Immobility can cause several complications, including skeletal muscle atrophy and weakness, that influence the recovery of critically ill patients. This effect can be mitigated by early mobilization. Six key questions guided this research: Is early mobilization safe? Which patients are candidates for early mobilization? What are the contraindications? What is the appropriate dose, and how should it be defined? What results are obtained? What are the prognostic indicators for the use of early mobilization? The objective of this guideline was to produce a document that would provide evidence-based recommendations and suggestions regarding the early mobilization of critically ill adult patients, with the aim of improving understanding of the topic and making a positive impact on patient care.

Accuracy of chest auscultation in detecting abnormal respiratory mechanics in the immediate postoperative period after cardiac surgery.

Objective: To investigate the accuracy of chest auscultation in detecting abnormal respiratory mechanics.

Methods: We evaluated 200 mechanically ventilated patients in the immediate postoperative period after cardiac surgery. We assessed respiratory system mechanics - static compliance of the respiratory system (Cst,rs) and respiratory system resistance (R,rs) - after which two independent examiners, blinded to the respiratory system mechanics data, performed chest auscultation.

Effects of repetitive transcranial magnetic stimulation of upper airway muscles during sleep in obstructive sleep apnea patients.

We tested the hypothesis that stimulating the genioglossus by repetitive transcranial magnetic stimulation (rTMS) during the ascendant portion of the inspiratory flow of airflow-limited breaths would sustain the recruitment of upper airway dilator muscles over time and improve airway dynamics without arousing obstructive sleep apnea (OSA) patients. In a cross-sectional design, nine OSA patients underwent a rTMS trial during stable non-rapid eye movement (NREM) sleep. Submental muscle motor threshold (SUB) and motor-evoked potential were evaluated during wakefulness and sleep.

Prevalence of lung structure abnormalities in patients with acromegaly and their relationship with gas exchange: cross-sectional analytical study with a control group.

Context And Objective: Different functional respiratory alterations have been described in acromegaly, but their relationship with pulmonary tissue abnormalities is unknown. The objective of this study was to observe possible changes in lung structure and explain their relationship with gas exchange abnormalities.

Design And Setting: Cross-sectional analytical study with a control group, conducted at a university hospital.

Mechanical effects of repetitive transcranial magnetic stimulation of upper airway muscles in awake obstructive sleep apnoea subjects.

New Findings: What is the central question of this study? Can repetitive transcranial magnetic stimulation (rTMS) of the genioglossus enhance the beneficial effects observed with transcranial magnetic stimulation single twitches on upper airway mechanical properties? What is the main finding and its importance? We found that both inspiratory and expiratory rTMS protocols induce a different activation pattern of upper airway muscles, with evidence for an increase in genioglossus corticomotor excitability in response to rTMS. This is of major importance because it might open the door for rTMS protocols with the goal of increasing corticomotor excitability and, thus, possibly increasing the tonic genioglossus activity, which is known to be diminished during sleep in subjects with sleep apnoea.

Abstract: Stimulation of upper airway (UA) muscles during sleep by isolated transcranial magnetic stimulation (TMS) twitch can improve airflow dynamics without arousal, but the effect of repetitive TMS (rTMS) on UA dynamics is unknown.

Accuracy of pulmonary auscultation to detect abnormal respiratory mechanics: a cross-sectional diagnostic study.

Pulmonary auscultation is a method used in clinical practice for the evaluation and detection of abnormalities relating to the respiratory system. This method has limitations, as it depends on the experience and hearing acuity of the examiner to determine adventitious sounds. In this context, it's important to analyze whether there is a correlation between auscultation of lung sounds and the behavior of the respiratory mechanical properties of the respiratory system in patients with immediate postoperative cardiac surgery.

Pulmonary arterial hypertension and sepsis: prothrombotic profile and inflammation can changes pulmonary mechanics?

Pulmonary arterial hypertension (PAH) is associated to cellular and structural alterations of lung vasculature. Endothelial dysfunction promotes vasoconstriction, smooth muscle hypertrophy, intimal proliferation, angioproliferative plexiform lesions, and in situ thrombosis increasing pulmonary vascular resistance and arterial stiffness. Indeed, an inflammatory component has been defined in PAH on the last years.

Impact of stepwise mandibular advancement on upper airway mechanics in obstructive sleep apnea using phrenic nerve magnetic stimulation.

Mandibular advancement devices (MAD) represent a potential treatment for obstructive sleep apnea (OSA). However, their mechanisms of actions are not completely understood. This study was aimed to explore the effects of MAD-induced mandibular protrusion on upper airway mechanics.

Levofloxacin decreased chest wall mechanical inhomogeneities and airway and vascular remodeling in rats with induced hepatopulmonary syndrome.

The administration of antibiotics decreases bacterial translocation, reduces the activity of nitric oxide synthase and improves the gas exchange of hepatopulmonary syndrome (HPS) in rats. We hypothesized that levofloxacin could reduce HPS-induced respiratory mechanical inhomogeneities and airway and pulmonary vascular remodeling. We assessed the respiratory mechanical properties and lung tissue structure in 24 rats assigned to the control, HPS (eHPS) and HPS+levofloxacin (eHPS+L) groups.

Consecutive transcranial magnetic stimulation twitches reduce flow limitation during sleep in apnoeic patients.

What is the central question of this study? A transcranial magnetic stimulation (TMS)-induced twitch applied on isolated single breaths over the motor cortex somatotopic representation of the tongue briefly recruits submental muscles and improves airflow dynamics of flow-limited respiratory cycles without arousing sleep apnoea patients. However, the mechanical impact of the TMS-induced twitch applied during consecutive breathing cycles on airflow dynamics remains unknown. What is the main finding and what is its importance? Our results show that application of TMS with the stimulator output set at the sleep submental motor threshold intensity on consecutive respiratory cycles increases inspiratory flow and reduces the turbulent airflow component.

Acute upper airway muscle and inspiratory flow responses to transcranial magnetic stimulation during sleep in apnoeic patients.

Transcranial magnetic stimulation (TMS) can activate the corticobulbar system and briefly recruit upper airway dilator muscles, improving the inspiratory airflow dynamics of flow-limited respiratory cycles during sleep. The purpose of this investigation was to quantify the effects of TMS-induced twitches applied during sleep on flow-limited respiratory cycles in 14 obstructive sleep apnoea patients. Submental muscle motor threshold (SUB(MT)) and motor-evoked potential (SUB(MEP)) were examined during wakefulness and sleep.

Impact of CPAP interface and mandibular advancement device on upper airway mechanical properties assessed with phrenic nerve stimulation in sleep apnea patients.

Oronasal mask (ONM) can be used when mouth leaks impair nasal-CPAP effectiveness. However, ONM's constraint on the chin and straps' traction may alter upper airway (UA) mechanical properties. In contrast, mandibular advancement device associated with nasal-CPAP (NM+MAD) may reduce UA resistance.

Assessment of upper airway dynamics by anterior magnetic phrenic stimulation in conscious sleep apnea patients.

Phrenic nerve magnetic stimulation (PNMS) performed anterolaterally at the base of the neck (BAMPS) and cervical magnetic stimulation are common techniques for assessing upper airway (UA) mechanical properties in conscious humans. We considered that if NMS performed at the sternal level (a-MS) could induce a similar percentage of flow-limited twitches as BAMPS in conscious subjects, gauging UA dynamic properties by PNMS would be simplified. Instantaneous flow, pharyngeal and esophageal pressures, as well as thoraco-abdominal motion were recorded in 10 conscious sleep apnea patients.