Advertisement

Topics

Assessing Respiratory Variability During Mechanical Ventilation in Acute Lung Injury (ALI)

2014-08-27 03:15:23 | BioPortfolio

Summary

Healthy biological systems are characterized by a normal range of "variability" in organ function. For example, many studies of heart rate clearly document that loss of the normal level of intrinsic, beat-to-beat variability in heart rate is associated with poor prognosis and early death.

Unlike the heart, little is known about patterns of respiratory variability in illness. What is known is that, like the heart, healthy subjects have a specific range of variability in breath- to-breath depth and timing. Additionally, in animal models, ventilator strategies that re-introduce normal variability to the breathing pattern significantly reduce ventilator-associated lung injury.

Critically ill patients requiring mechanical ventilation offer an opportunity to observe and analyze respiratory patterns in a completely non-invasive manner. Current mechanical ventilators produce real-time output of respiratory tracings that can analyzed for variability.

The investigators propose to non-invasively record these tracings from patients ventilated in the intensive care units for mathematical variability analysis. The purpose of these pilot analyses are to: (1) demonstrate the range of respiratory variability present in the mechanically ve ventilated critically ill and (2) demonstrate the ventilator modality that delivers or permits the closest approximation to previously described beneficial or normal levels of variability. Future studies will use this pilot data in order to determine if the observed patterns of respiratory variability in mechanically ventilated critically ill subjects have prognostic or therapeutic implications.

Description

Different modes of mechanical ventilation allow different levels of patient control of the respiratory pattern. For example, the most common mode of ventilation, called volume control, gives very little control to the patient in the amount of air taken for each breath. Other modes, such as pressure control, pressure regulated volume control and pressure support, allow more patient control of the volume of air delivered by the ventilator. Newer modes, such as airway pressure release ventilation (APRV), allow completely spontaneous patient respirations. All of these modes allow at least some patient control of respiratory rates.

Studies of natural breathing by healthy subjects have shown normal levels of variability in respiratory rate and tidal volume.1 Variability in physiological processes has been associated with health and the loss of variability can presage the onset of illness. For example, normal humans exposed to LPS (lipopolysaccharide-the potent immune-stimulating cell wall component of bacteria) lose their normal respiratory variability. Thus, physiological variability may represent a "hidden vital sign," the monitoring of which may herald important clinical events. Additionally, re-establishing normal levels of variability has therapeutic benefits in animal models. 2

The variability in respiratory patterns in ill patients has not been well studied. For example, it is currently unclear if critical illness results in deviations from normal variability patterns, if ventilator modes allowing increasing patient control of respiration allow patients to attain greater normalcy of respiratory variability, or if deviations from normal respiratory patterns while on ventilator modes which allow for increased levels of spontaneous breathing have prognostic implications.

The purpose of this pilot study is to record respiratory patterns from the ventilators of patients receiving various modes of mechanical ventilation in order to quantify and compare levels of respiratory variability associated with each mode. Our hypothesis is that APRV, a mode that allows spontaneous respiration, will be associated with respiratory variability patterns that most closely approximate that of normal subjects.

We hope that data derived from this study will inform future observational studies correlating respiratory variability during mechanical ventilation with severity of illness and prognosis.

Study Design

Observational Model: Case Control, Time Perspective: Prospective

Conditions

Acute Lung Injury

Location

Boston Medical Center
Boston
Massachusetts
United States
02118

Status

Not yet recruiting

Source

Boston Medical Center

Results (where available)

View Results

Links

Published on BioPortfolio: 2014-08-27T03:15:23-0400

Clinical Trials [2204 Associated Clinical Trials listed on BioPortfolio]

Incidence of Acute Lung Injury in Children

Acute lung injury in children is a syndrome of rapid onset of acute respiratory failure and require admission into intensive care units (ICU) for advanced life support. There are almost no...

Acute Lung Injury After Cardiac Surgery: Pathogenesis

The purpose of the present study is to visualize the inflammatory response and coagulation disorders during cardiac surgery in order to identify possible predictors for acute lung injury p...

Regional Lung Opening and Closing Pressures in Patients With Acute Lung Injury

The purpose of this study is the measurement of regional opening and closing pressures of lung tissue by electrical impedance tomography in lung healthy and patients with acute lung injury...

Morphofunctional Lung Analysis by Positron Emission Tomography

Patients affected by acute lung injury-acute respiratory distress syndrome (ALI-ARDS) undergo a positron emission tomography (PET) scan in order to analyse lung function.

Timing and Intensity of the Exposures and Attributable Burden of Acute Lung Injury

The purpose of the study is to identify the patients at high risk of developing Acute Lung Injury (ALI) at the time of hospital admission, and before intensive care unit admission. Aim 1-...

PubMed Articles [13199 Associated PubMed Articles listed on BioPortfolio]

Apelin-13 Administration Protects Against LPS-Induced Acute Lung Injury by Inhibiting NF-κB Pathway and NLRP3 Inflammasome Activation.

Acute lung injury (ALI) is induced by a variety of external and internal factors and leads to acute progressive respiratory failure. Previous studies have shown that apelin-13 can decrease the acute l...

A Conserved Distal Lung Regenerative Pathway in Acute Lung Injury.

Improved tools have led to a burgeoning understanding of lung regeneration in mice, but it is not yet known how these insights may be relevant to acute lung injury in humans. We report in detail two c...

The Emerging Role of Neutrophils in Repair after Acute Lung Injury.

Neutrophils are key players in acute lung injury. Once recruited from the circulation, these cells release cytotoxic molecules that lead to tissue disruption, so their blockade has been advocated to p...

Ulinastatin protects rats from sepsis-induced acute lung injury by suppressing the JAK-STAT3 pathway.

Sepsis is usually accompanied by pulmonary inflammations, leading to acute lung injury. During this process, endogenous factors that play a regulatory role could be exploited to therapeutically allevi...

G-CSF mediates lung injury in mice with adenine-induced acute kidney injury.

Acute lung injury (ALI) is a serious complication among patients with acute kidney injury (AKI) that is a systemic inflammatory disease with high morbidity and mortality. The pathophysiology of AKI-as...

Medical and Biotech [MESH] Definitions

A rare but serious transfusion-related reaction in which fluid builds up in the lungs unrelated to excessively high infusion rate and/or volume (TRANSFUSION-ASSOCIATED CIRCULATORY OVERLOAD). Signs of Transfusion-Related Acute Lung Injury include pulmonary secretions; hypotension; fever; DYSPNEA; TACHYPNEA; TACHYCARDIA; and CYANOSIS.

Damage to any compartment of the lung caused by physical, chemical, or biological agents which characteristically elicit inflammatory reaction. These inflammatory reactions can either be acute and dominated by NEUTROPHILS, or chronic and dominated by LYMPHOCYTES and MACROPHAGES.

A condition of lung damage that is characterized by bilateral pulmonary infiltrates (PULMONARY EDEMA) rich in NEUTROPHILS, and in the absence of clinical HEART FAILURE. This can represent a spectrum of pulmonary lesions, endothelial and epithelial, due to numerous factors (physical, chemical, or biological).

Abrupt reduction in kidney function defined as an absolute increase in serum CREATININE of more than or equal to 0.3. mg/dl, a percentage increase in serum creatinine of more than or equal to 50%, or a reduction in urine output. Acute kidney injury encompasses the entire spectrum of the syndrome including acute kidney failure; ACUTE KIDNEY TUBULAR NECROSIS; and other less severe conditions.

Injury following pressure changes; includes injury to the eustachian tube, ear drum, lung and stomach.

More From BioPortfolio on "Assessing Respiratory Variability During Mechanical Ventilation in Acute Lung Injury (ALI)"

Advertisement
Quick Search
Advertisement
Advertisement

 

Relevant Topics

Nutrition
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...

Biological Therapy
Biological therapy involves the use of living organisms, substances derived from living organisms, or laboratory-produced versions of such substances to treat disease. Some biological therapies for cancer use vaccines or bacteria to stimulate the body&rs...

Cardiovascular disease (CVD)
Acute Coronary Syndromes (ACS) Blood Cardiovascular Dialysis Hypertension Stent Stroke Vascular Cardiovascular disease (CVD) includes all the diseases of the heart and circulation including coronary heart disease (angina...


Searches Linking to this Trial