Sympathetic Neural Outflow and Chemoreflex Sensitivity Are Related to Spontaneous Breathing Rate in Normal Men

Airway resistance was measured with a volume displacement body plethysmograph in 40 normal subjects breathing at their spontaneous breathing rate. The measurements are based on a method designed by DuBois et al. which was modified in order to extend its applicability. The subjects were rebreathing from a bag containing gas at approximately BTPS conditions. Possible errors in conditioning the gas in the bag were corrected mathematically. The values of airway resistance obtained (1.26 ± .39 cm H2O/liter-1 sec) agree with those published by DuBois et al. and other authors using his technique. The measurements were found to correlate with results obtained on the same subjects with related techniques. The paper also includes measurements of lung tissue viscous resistance and inertance of the gas in the airways. respiratory mechanics; mechanics of breathing; airway inertance; lung tissue viscance Submitted on November 22, 1963

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Comparison of spontaneous vs. metronome-guided breathing on assessment of vagal modulation using RR variability

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.280.3.h1145 ◽

2001 ◽

Vol 280 (3) ◽

pp. H1145-H1150 ◽

Cited By ~ 65

Author(s):

Daniel M. Bloomfield ◽

Anthony Magnano ◽

J. Thomas Bigger ◽

Harold Rivadeneira ◽

Michael Parides ◽

...

Keyword(s):

High Frequency ◽

Spontaneous Breathing ◽

Healthy Subjects ◽

Sinus Node ◽

Cardiac Patients ◽

Breathing Rate ◽

Autonomic Activity ◽

Vagal Modulation ◽

Significant Difference ◽

Rr Variability

R-R interval variability (RR variability) is increasingly being used as an index of autonomic activity. High-frequency (HF) power reflects vagal modulation of the sinus node. Since vagal modulation occurs at the respiratory frequency, some investigators have suggested that HF power cannot be interpreted unless the breathing rate is controlled. We hypothesized that HF power during spontaneous breathing would not differ significantly from HF power during metronome-guided breathing. We measured HF power during spontaneous breathing in 20 healthy subjects and 19 patients with heart disease. Each subject's spontaneous breathing rate was determined, and the calculation of HF power was repeated with a metronome set to his or her average spontaneous breathing rate. There was no significant difference between the logarithm of HF power measured during spontaneous and metronome-guided breathing [4.88 ± 0.29 vs. 5.29 ± 0.30 ln(ms2), P = 0.32] in the group as a whole and when patients and healthy subjects were examined separately. We did observe a small (9.9%) decrease in HF power with increasing metronome-guided breathing rates (from 9 to 20 breaths/min). These data indicate that HF power during spontaneous and metronome-guided breathing differs at most by very small amounts. This variability is several logarithmic units less than the wide discrepancies observed between healthy subjects and cardiac patients with a heterogeneous group of cardiovascular disorders. In addition, HF power is relatively constant across the range of typical breathing rates. These data indicate that there is no need to control breathing rate to interpret HF power when RR variability (and specifically HF power) is used to identify high-risk cardiac patients.

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Prediction of the effectiveness of spontaneous breathing in patients with brain damage of various etiologies

Annals of the Russian academy of medical sciences ◽

10.15690/vramn1203 ◽

2020 ◽

Vol 74 (6) ◽

pp. 371-377

Author(s):

Yuri Y. Kiryachkov ◽

Marina V. Petrova ◽

Alexandr L. Parfenov ◽

Anatoly A. Loginov ◽

Artem E. Skvortsov

Keyword(s):

Brain Damage ◽

Spontaneous Breathing ◽

Minute Ventilation ◽

Stress Test ◽

Severe Heart Failure ◽

Successful Recovery ◽

Starting Point ◽

Level Of Consciousness ◽

Chemoreflex Sensitivity ◽

Peripheral Chemoreflex

BACKGROUND: Long-term respiratory support is a severe disabling factor and is accompanied by a long stay of patients in intensive care units. AIMS: The analysis of the predictors of the success of disconnection from mechanical ventilation on the basis of clinical and diagnostic criteria in patients with brain damage of various etiologies. METHODS: The study included 53 patients (husband ― 28, women ― 25; cf. age 53.69 2.34) who are in 2019 with the consequences of traumatic brain injury (TBI) (n = 18; 33.9%); consequences of acute cerebrovascular accident (n = 24; 45.3%); the effects of anoxic brain damage (n = 3; 5.7%); consequences of subarachnoid hemorrhage (n = 8; 15.1%). RESULTS: The statistically significant predictor of recovery of spontaneous breathing in the 1st and 2nd groups of patients were preserved chemoreflex sensitivity (IPCS), the sensitivity and specificity of IPCS was 78.57% [95 % DI 49.295.26] and 83.3 % [95 % CI 62.695.26]. The index of peripheral chemoreflex sensitivity (IPCS) was calculated using the formula: IPCS = [RRe / RRi] [Vt(e) / Vt(i)] [VE(e) / VE(i)] [Vt(e) VE(i)], where IPCS is the index of peripheral chemoreflex sensitivity in l/min; RRi and RRe; Vt(i) and Vt(e); VE(e) and VE(i) ― respiratory rate (RR, breaths/min), tidal volume (Vt), minute ventilation (VE), (l/min) of the starting point ― (i) before carrying out a functional stress test and (e) ― during a functional test of normobaric hypoxia with SpO2 in the range of 9080 %. CONCLUSIONS: The most significant clinical parameters statistically reliably hampering the process of successful recovery of spontaneous breathing in addition to chemoreflex sensitivity are the presence of severe heart failure, pneumonia, autonomic dysfunction, level of consciousness, age, higher levels of inspiratory and expiratory pressure mounted on a respirator.

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Incidence of Gall Bladder Disease in “Normal” Men

Gastroenterology ◽

10.1016/s0016-5085(59)80010-x ◽

1959 ◽

Vol 36 (2) ◽

pp. 251-255 ◽

Cited By ~ 23

Author(s):

Richard S. Wilbur ◽

Robert J. Bolt

Keyword(s):

Gall Bladder ◽

Gall Bladder Disease ◽

Bladder Disease ◽

Normal Men

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Forced oscillation total respiratory resistance and spontaneous breathing lung resistance in COPD patients

European Respiratory Journal ◽

10.1034/j.1399-3003.1999.14a29.x ◽

1999 ◽

Vol 14 (1) ◽

pp. 172 ◽

Cited By ~ 20

Author(s):

R. Farré ◽

R. Peslin ◽

M. Rotger ◽

J Barberá ◽

D Navajas

Keyword(s):

Spontaneous Breathing ◽

Forced Oscillation ◽

Respiratory Resistance ◽

Copd Patients ◽

Lung Resistance

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Serum uric acid, cholesterol, and cortisol levels: Interrelationships in normal men under stress.

PsycEXTRA Dataset ◽

10.1037/e467332004-001 ◽

1970 ◽

Author(s):

Robert T. Rubin ◽

Richard H. Rahe ◽

Brian R. Clark ◽

Ransom J. Arthur

Keyword(s):

Uric Acid ◽

Serum Uric Acid ◽

Cortisol Levels ◽

Normal Men

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ÉTUDES IN VIVO SUR LE MÉTABOLISME DES ANDROGÉNES APRES ADMINISTRATION DE STÉROÏDES INHIBITEURS DE L'OVULATION

Acta Endocrinologica ◽

10.1530/acta.0.0500131 ◽

1965 ◽

Vol 50 (1) ◽

pp. 131-144 ◽

Cited By ~ 1

Author(s):

P. Mauvais-Jarvis ◽

M. F. Jayle ◽

J. Decourt ◽

J. Louchart ◽

J. Truffert

Keyword(s):

Luteinizing Hormone ◽

Urinary Excretion ◽

Normal Subjects ◽

Hormone Activity ◽

Testosterone Production ◽

Normal Men ◽

Ethinyl Oestradiol

ABSTRACT Normal subjects and hirsute women with micropolycystic ovaries were treated with ethinyl-oestrenol + 3-methoxy-ethinyl-oestradiol (Lyndiol®), in view of studying the action of this compound on the production of androgens and on the urinary excretion of their metabolites. In normal men, the production of testosterone and the excretion of androsterone and aetiocholanolone are suppressed, whereas the excretion of other 17-ketosteroids and the production of dehydroepiandrosterone sulphate are unchanged. Moreover, the luteinizing hormone activity (LH) in plasma is depressed. It seems that the preparation inhibits specifically the testicular androgen production, by suppressing the hypothalamo-hypophyseal control of LH. Testosterone production and urinary 17-ketosteroid excretion are modified in the same way in women with Stein-Leventhal's syndrome. Physiopathological and therapeutical implications which come from these results are discussed.

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SUPRESSION OF ANDROGEN AND OESTROGEN PRODUCTION IN NORMAL MEN

Acta Endocrinologica ◽

10.1530/acta.0.0700342 ◽

1972 ◽

Vol 70 (2) ◽

pp. 342-350 ◽

Cited By ~ 6

Author(s):

M. A. Kirschner ◽

D. W. R. Knorr

Keyword(s):

Urine Sample ◽

Plasma Testosterone ◽

Low Level ◽

Normal Men

ABSTRACT An attempt was made to suppress production of androgens and oestrogens in normal men by administering large doses of exogenous androgens and corticoids. After 5 days of 40 mg fluoxymesterone qd, plasma testosterone concentrations decreased from 509 to 73 ng/100 ml (85%); on adding 8 mg qd of dexamethasone, there was a further decrease to 45 ng/100 ml. Androstenedione concentrations were decreased equally by fluoxymesterone and corticoids. To monitor the suppressive effects of exogenous steroids, urinary LH was followed serially by radioimmunoassay, and decreased to only 40% of control levels after 5 days of fluoxymesterone, with no further suppression noted on adding dexamethasone. Nanogram quantities of steroidal metabolites were not adsorbed by kaolin extraction of urine, thus enabling gonadotrophins (kaolin extract) and low-level steroids (supernate) to be measured in the same urine sample. Urinary oestrone and oestradiol excretion decreased during 5 days of fluoxymesterone, and continued to fall when dexamethasone was added. In no case was oestrone or oestradiol excretion, urinary LH or plasma androgens completely suppressed by large doses of fluoxymesterone alone, or in combination with large doses of dexamethasone.

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