Effort sensation, chemoresponsiveness, and breathing pattern during inspiratory resistive loading
| Autor: | M. G. Pearson, J. Carter, Pma Calverley, J. E. Clague |
|---|---|
| Rok vydání: | 1992 |
| Předmět: |
Adult
Male medicine.medical_specialty Physiology Physical Exertion Respiratory physiology pCO2 Hypercapnia Physiology (medical) Internal medicine Sensation Respiration Humans Medicine Tidal volume Resistive touchscreen business.industry Carbon Dioxide Chemoreceptor Cells Respiratory Function Tests Surgery Respiratory Mechanics Breathing Cardiology medicine.symptom business |
| Zdroj: | Journal of Applied Physiology. 73:440-445 |
| ISSN: | 1522-1601 8750-7587 |
| DOI: | 10.1152/jappl.1992.73.2.440 |
| Popis: | Although inspiratory resistive loading (IRL) reduces the ventilatory response to CO2 (VE/PCO2) and increases the sensation of inspiratory effort (IES), there are few data about the converse situation: whether CO2 responsiveness influences sustained load compensation and whether awareness of respiratory effort modifies this behavior. We studied 12 normal men during CO2 rebreathing while free breathing and with a 10-cmH2O.l-1.s IRL and compared these data with 5 min of resting breathing with and without the IRL. Breathing pattern, end-tidal PCO2, IES, and mouth occlusion pressure (P0.1) were recorded. Free-breathing VE/PCO2 was inversely related to an index of effort perception (IES/VE; r = -0.63, P less than 0.05), and the reduction in VE/PCO2 produced by IRL was related to the initial free-breathing VE/PCO2 (r = 0.87, P less than 0.01). IRL produced variable increases in inspiratory duration (TI), IES, and P0.1 at rest, and the change in tidal volume correlated with both VE/PCO2 (r = 0.63, P less than 0.05) and IES/VE (r = -0.69, P less than 0.05), this latter index also predicting the changes in TI with loading (r = -0.83, P less than 0.01). These data suggest that in normal subjects perception of inspiratory effort can modify free-breathing CO2 responsiveness and is as important as CO2 sensitivity in determining the response to short-term resistive loading. Individuals with good perception choose a small-tidal volume and short-TI breathing pattern during loading, possibly to minimize the discomfort of breathing. |
| Databáze: | OpenAIRE |
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