Respiratory resistance during emotional stimulation: evidence for a nonspecific effect of experienced arousal?

Purpose An investigational, portable instrument was used to assess inspiratory (R i ) and expiratory (R e ) resistances during resting tidal breathing (RTB), postexercise breathing (PEB), and recovery breathing (RB) in athletes with and without paradoxical vocal fold motion disorder (PVFMD). Method Prospective, controlled, repeated measures within-subject and between-groups design. Twenty-four teenage female athletes, 12 with and 12 without PVFMD, breathed into the Airflow Perturbation Device for baseline measures of respiratory resistance and for two successive 1-min trials after treadmill running for up to 12 min. Exercise duration and dyspnea ratings were collected and compared across groups. Results Athletes with PVFMD had lower than control R i and R e values during RTB that significantly increased at PEB and decreased during RB. Control athletes' R e decreased significantly from RTB to PEB but not from PEB to RB, whereas R i did not change from RTB to PEB but decreased from PEB to RB. Athletes without PVFMD ran longer, providing lower dyspnea ratings. Conclusion Immediately following exercise, athletes with PVFMD experienced increased respiratory resistance that affected their exercise performance. The difference in resting respiratory resistances between groups is intriguing and could point to anatomical differences or neural adaptation in teenagers with PVFMD. The Airflow Perturbation Device appears to be a clinically feasible tool that can provide insight into PVFMD and objective data for tracking treatment progress.

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Is the specific effect of receiving oxaliplatin, or merely the nonspecific effect of having suffered cancer, the cause of Takotsubo syndrome?

Journal of Cardiovascular Medicine ◽

10.2459/jcm.0000000000000247 ◽

2016 ◽

Vol 17 (1) ◽

pp. 69 ◽

Cited By ~ 2

Author(s):

John E. Madias

Keyword(s):

Specific Effect ◽

Takotsubo Syndrome ◽

Nonspecific Effect

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Evaluation of Respiratory Resistance as a Predictor for Oral Appliance Treatment Response in Obstructive Sleep Apnea: A Pilot Study

Journal of Clinical Medicine ◽

10.3390/jcm10061255 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1255

Author(s):

Hiroyuki Ishiyama ◽

Masayuki Hideshima ◽

Shusuke Inukai ◽

Meiyo Tamaoka ◽

Akira Nishiyama ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Pilot Study ◽

Reduction Rate ◽

Oral Appliance ◽

Respiratory Resistance ◽

Obstructive Sleep ◽

Respiratory Event ◽

Significant Difference ◽

Treatment Responses

The aim of this study was to determine the utility of respiratory resistance as a predictor of oral appliance (OA) response in obstructive sleep apnea (OSA). Twenty-seven patients with OSA (mean respiratory event index (REI): 17.5 ± 6.5 events/h) were recruited. At baseline, the respiratory resistance (R20) was measured by impulse oscillometry (IOS) with a fitted nasal mask in the supine position, and cephalometric radiographs were obtained to analyze the pharyngeal airway space (SPAS: superior posterior airway space, MAS: middle airway space, IAS: inferior airway space). The R20 and radiographs after the OA treatment were evaluated, and the changes from the baseline were analyzed. A sleep test with OA was carried out using a portable device. The subjects were divided into Responders and Non-responders based on an REI improvement ≥ 50% from the baseline, or REI < 5 after treatment, and the R20 reduction rate between the two groups were compared. The subjects comprised 20 responders and 7 non-responders. The R20 reduction rate with OA in responders was significantly greater than it was in non-responders (14.4 ± 7.9 % versus 2.4 ± 9.8 %, p < 0.05). In responders, SPAS, MAS, and IAS were significantly widened and R20 was significantly decreased with OA (p < 0.05). There was no significant difference in non-responders (p > 0.05). A logistic multiple regression analysis showed that the R20 reduction rate was predictive for OA treatment responses (2% incremental odds ratio (OR), 24.5; 95% CI, 21.5–28.0; p = 0.018). This pilot study confirmed that respiratory resistance may have significant clinical utility in predicting OA treatment responses.

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Respiratory input impedance in anesthetized paralyzed patients

Journal of Applied Physiology ◽

10.1152/jappl.1990.69.4.1372 ◽

1990 ◽

Vol 69 (4) ◽

pp. 1372-1379 ◽

Cited By ~ 43

Author(s):

D. Navajas ◽

R. Farre ◽

J. Canet ◽

M. Rotger ◽

J. Sanchis

Keyword(s):

Mechanical Model ◽

Forced Oscillation ◽

Respiratory Resistance ◽

Frequency Range ◽

Entire Frequency Range ◽

Peripheral Airways ◽

Distal Branch ◽

Low Amplitude ◽

Gas Compressibility ◽

Central Airway

Respiratory impedance (Zrs) was measured between 0.25 and 32 Hz in seven anesthetized and paralyzed patients by applying forced oscillation of low amplitude at the inlet of the endotracheal tube. Effective respiratory resistance (Rrs; in cmH2O.l-1.s) fell sharply from 6.2 +/- 2.1 (SD) at 0.25 Hz to 2.3 +/- 0.6 at 2 Hz. From then on, Rrs decreased slightly with frequency down to 1.5 +/- 0.5 at 32 Hz. Respiratory reactance (Xrs; in cmH2O.l-1.s) was -22.2 +/- 5.9 at 0.25 Hz and reached zero at approximately 14 Hz and 2.3 +/- 0.8 at 32 Hz. Effective respiratory elastance (Ers = -2pi x frequency x Xrs; in cmH2O/1) was 34.8 +/- 9.2 at 0.25 Hz and increased markedly with frequency up to 44.2 +/- 8.6 at 2 Hz. We interpreted Zrs data in terms of a T network mechanical model. We represented the proximal branch by central airway resistance and inertance. The shunt pathway accounted for bronchial distensibility and alveolar gas compressibility. The distal branch included a Newtonian resistance component for tissues and peripheral airways and a viscoelastic component for tissues. When the viscoelastic component was represented by a Kelvin body as in the model of Bates et al. (J. Appl. Physiol. 61: 873-880, 1986), a good fit was obtained over the entire frequency range, and reasonable values of parameters were estimated. The strong frequency dependence of Rrs and Ers observed below 2 Hz in our anesthetized paralyzed patients could be mainly interpreted in terms of tissue viscoelasticity. Nevertheless, the high Ers we found with low volume excursions suggests that tissues also exhibit plasticlike properties.

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Respiratory dynamic resistance

Journal of Applied Physiology ◽

10.1152/jappl.1962.17.4.609 ◽

1962 ◽

Vol 17 (4) ◽

pp. 609-612 ◽

Cited By ~ 8

Author(s):

Ernest Croft Long ◽

Wayland Elroy Hull ◽

Emile Louis Gebel

Keyword(s):

Respiratory Cycle ◽

Dynamic Resistance ◽

Respiratory Resistance ◽

Differential Coefficient ◽

Energy Dissipated ◽

Nonlinear Resistance

Sinusoidal forcing at frequencies up to 17 cycles/sec was applied to the anesthetized, apneic dog by a body respirator. Forcing pressure and volume displacement were displayed in quadrature on an oscilloscope and planimetric integration of these loops indicated an increase in energy dissipated by total respiratory resistance per liter of air displaced, due to turbulence and changing airway geometry, with increasing frequency. Nonlinear resistance was calculated and the differential coefficient, dP/dV (dynamic resistance), was determined at 10° intervals throughout the respiratory cycle, at each of three frequencies in four dogs. Total respiratory resistance is a “nonohmic” dependent variable and changes progressively throughout the cycle. Submitted on October 20, 1961

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