Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

To evaluate the response of normal subjects to assisted ventilation, we studied 6 naive healthy subjects before and during negative-pressure ventilation (NPV) with "low" (-10 cmH2O) and "high" (-30 cmH2O) pressures in an Emerson tank respirator. Ventilation was measured with an inductive plethysmograph (Respitrace), and diaphragmatic electromyogram (DEMG) was studied with a bipolar esophageal electrode. During NPV a 1:1 phase lock was observed between subjects and iron lung frequency in all subjects. Tidal volume increased in most subjects, more with high than with low pressures (P less than 0.05), whereas DEMG increased, decreased, or showed no change. Postinspiratory inspiratory diaphragmatic activity (PIIA) significantly increased during high-pressure NPV and was accompanied by an increase in tonic DEMG in one-half of the subjects. Voluntary relaxation resulted in a decrease in DEMG and PIIA. We suggest that cortical activity can explain persistency of active breathing during negative-pressure ventilation.

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Sustained Improvement in Gas Exchange After Negative Pressure Ventilation for 8 Hours Per Day on 2 Successive Days in Chronic Airflow Limitation

American Review of Respiratory Disease ◽

10.1164/ajrccm/144.2.390 ◽

1991 ◽

Vol 144 (2) ◽

pp. 390-394 ◽

Cited By ~ 14

Author(s):

Enrique Fernandez ◽

Paltiel Weiner ◽

Ephraim Meltzer ◽

Mary M. Lutz ◽

David B. Badish ◽

...

Keyword(s):

Gas Exchange ◽

Negative Pressure ◽

Airflow Limitation ◽

Sustained Improvement ◽

Negative Pressure Ventilation

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Negative pressure ventilation decreases inflammation and lung edema during normothermic ex-vivo lung perfusion

The Journal of Heart and Lung Transplantation ◽

10.1016/j.healun.2017.09.007 ◽

2018 ◽

Vol 37 (4) ◽

pp. 520-530 ◽

Cited By ~ 16

Author(s):

Nader S. Aboelnazar ◽

Sayed Himmat ◽

Sanaz Hatami ◽

Christopher W. White ◽

Mohamad S. Burhani ◽

...

Keyword(s):

Negative Pressure ◽

Ex Vivo ◽

Lung Perfusion ◽

Lung Edema ◽

Ex Vivo Lung Perfusion ◽

Negative Pressure Ventilation

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Negative pressure ventilation for infants with respiratory failure after cardiac surgery

Pediatric Anesthesia ◽

10.1111/j.1460-9592.1992.tb00479.x ◽

1992 ◽

Vol 2 (1) ◽

pp. 45-50

Author(s):

D. S. JARDINE ◽

A. COSTARINO

Keyword(s):

Cardiac Surgery ◽

Respiratory Failure ◽

Negative Pressure ◽

Negative Pressure Ventilation

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Augmentation of phrenic neural activity by increased rates of lung inflation

Journal of Applied Physiology ◽

10.1152/jappl.1981.50.1.149 ◽

1981 ◽

Vol 50 (1) ◽

pp. 149-161 ◽

Cited By ~ 39

Author(s):

A. I. Pack ◽

R. G. DeLaney ◽

A. P. Fishman

Keyword(s):

Tidal Volume ◽

Volume Change ◽

Neural Activity ◽

Negative Pressure ◽

Spontaneous Breathing ◽

Moving Average ◽

Constant Flow ◽

Lung Inflation ◽

Negative Pressure Ventilation ◽

Single Breath

Studies were conducted in anesthetized paralyzed dogs using a cycle-triggered constant-flow ventilator, which ventilated the animal in phase with the recorded phrenic neural activity. Intermittently tests were performed in which the animal was ventilated with a different airflow for a single breath. Increased airflows, within the range generated during spontaneous breathing, caused an increased rate of rise of the moving average phrenic neurogram and a shortening of the duration of the nerve burst. The magnitude of the increase in the rate of rise of the neurogram was related to the level of inspiratory airflow. Tests with brief pulses of airflow showed that an increase in the rate of rise of the phrenic neurogram could be produced without inflating the lung above the resting tidal volume of the animal. Similar results were obtained with negative-pressure ventilation and the effects were abolished by vagotomy. This vagally mediated augmentation of phrenic neural output may accelerate the inspiratory volume change in the lung during spontaneous breathing at hyperpneic levels.

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Negative Pressure Ventilation as a Treatment Modality in Patients with Hyperinflation

Current Topics in Rehabilitation - Chronic Pulmonary Hyperinflation ◽

10.1007/978-1-4471-3782-5_19 ◽

1991 ◽

pp. 145-150

Author(s):

N. Ambrosino ◽

S. Nava ◽

C. Fracchia ◽

C. Rampulla

Keyword(s):

Negative Pressure ◽

Treatment Modality ◽

Negative Pressure Ventilation

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Diagnosis and validation by computational fluid dynamics of poultry house with negative pressure ventilation

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v23n10p761-767 ◽

2019 ◽

Vol 23 (10) ◽

pp. 761-767

Author(s):

Gisele C. de A. Cunha ◽

José P. Lopes Neto ◽

Dermeval A. Furtado ◽

Valéria P. Borges ◽

Elias A. Freire ◽

...

Keyword(s):

Thermal Comfort ◽

Negative Pressure ◽

Environmental Variables ◽

Fluid Dynamic ◽

Air Velocity ◽

Cfd Simulations ◽

Heterogeneous Distribution ◽

Poultry House ◽

Mean Values ◽

Negative Pressure Ventilation

ABSTRACT Negative pressure ventilation in poultry houses has been used to enable the correction of their internal microclimates, and studies point to the heterogeneous distribution of air along the aviaries and the inadequacy of the environmental variables to the recommended ranges for thermal comfort of adult birds, especially in the hottest hours of the day. This study aimed to diagnose the facilities of a poultry house in the state of Paraíba, Brazil, regarding the distribution of environmental variables and thermal comfort; develop a computational model and validate it for Computational Fluid Dynamic - CFD simulations. Air temperature (Tair), air relative humidity (RH) and air velocity (Vair) data allowed characterizing the internal environment by comparison with the recommended ranges for each variable and by the temperature-humidity-velocity index (THVI). The poultry house does not provide comfort for the housed adult birds, between 12 and 14 h, with THVI indicating alert and Tair, RH and Vair values outside the recommended ranges; the CFD model for the poultry house was validated with Tair averages collected in the field of 27.75 ± 1.35 ºC and simulated of 27.85 ± 0.55 ºC, mean values of RH collected of 83 ± 12% and simulated of 78 ± 3%, and means of Vair collected of 2.35 ± 1.35 m s-1 and simulated of 2.50 ± 1.50 m s-1.

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