Efficiency of the normal human diaphragm with hyperinflation.

@article{Finucane2005EfficiencyOT,
  title={Efficiency of the normal human diaphragm with hyperinflation.},
  author={Kevin E. Finucane and Janine A. Panizza and Bhajan Singh},
  journal={Journal of applied physiology},
  year={2005},
  volume={99 4},
  pages={
          1402-11
        }
}
We evaluated an index of diaphragm efficiency (Eff(di)), diaphragm power output (Wdi) relative to electrical activation, in five healthy adults during tidal breathing at usual end-expiratory lung volume (EELV) and diaphragm length (L(di ee)) and at shorter L(di ee) during hyperinflation with expiratory positive airway pressure (EPAP). Measurements were repeated with an inspiratory threshold (7.5 cmH(2)O) plus resistive (6.5 cmH(2)O.l(-1).s) load. Wdi was the product of mean inspiratory… 
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41 Citations
Background Citations
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Methods Citations
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Results Citations
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41 Citations

Citation Type

Citation Type

Human diaphragm efficiency estimated as power output relative to activation increases with hypercapnic hyperpnea.
TLDR
Eff(di) increased due to preinspiratory lengthening and inspiratory unloading of the diaphragm, consistent with muscle behavior in vitro, and phasic abdominal muscle activity with hyperpnea reduces diaphragem energy consumption.
Diaphragm efficiency estimated as power output relative to activation in chronic obstructive pulmonary disease.
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In COPD with modest airflow obstruction, Eff(di) did not increase normally with hyperpnea due to a constant L(di ee) and inspiratory flattening of the diaphragm.
Role of bronchodilation and pattern of breathing in increasing tidal expiratory flow with progressive induced hypercapnia in chronic obstructive pulmonary disease.
TLDR
In chronic obstructive pulmonary disease (COPD), progressive HC increases V̇exp due to bronchodilation, increased Pel secondary to decreasing Ti, and increased expiratory effort, all promoting lung emptying and a stable EELV.
Estimation of Patient’s Inspiratory Effort From the Electrical Activity of the Diaphragm*
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The derivation of the Pmusc/Eadi index from Eadi and airway pressure during an expiratory occlusion enables a continuous estimate of patient’s inspiratory effort, stable within each patient under different conditions of ventilator assistance.
Neuroventilatory efficiency and extubation readiness in critically ill patients
TLDR
This study shows that a mixed group of critically ill patients for whom weaning fails have increased neural respiratory drive and impaired ability to convert neuromuscular activity into tidal ventilation, in part because of diaphragm weakness.
Inspiratory resistive loading does not increase sympathetic tone in COPD.
Noninvasive Assessment of Neuromechanical Coupling and Mechanical Efficiency of Parasternal Intercostal Muscle during Inspiratory Threshold Loading
TLDR
The proposed nonin invasive NMC and MEff indices of parasternal intercostal muscles may be of potential clinical value, particularly for the regular assessment of patients with disordered respiratory mechanics using noninvasive wearable and wireless devices.
Effects of positive expiratory pressure on pulmonary clearance of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid in healthy individuals.
TLDR
The findings indicate that PEP, at the levels tested, is able to induce an increase in pulmonary epithelial membrane permeability and lung volume in healthy subjects.
Neuromuscular efficiency is impaired during exercise in COPD patients
Prospective Effects of Manual Diaphragmatic Release and Thoracic Lymphatic Pumping in Childhood Asthma
TLDR
The thoracic lymphatic pump technique and conventional respiratory retraining approaches were helpful interventions that could be used to alleviate the symptoms of childhood asthma, but the diaphragmatic release technique was a potentially more effective intervention.
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