Effect of transverse acceleration on pulmonary function

1959 ◽  
Vol 14 (6) ◽  
pp. 914-916 ◽  
Author(s):  
Neil S. Cherniack ◽  
Alvin S. Hyde ◽  
F. W. Zechman
Keyword(s):  
Pulmonary Function ◽  
Tidal Volume ◽  
Respiratory Rate ◽  
Centrifugal Force ◽  
Vital Capacity ◽  
Minute Volume ◽  
Respiratory Parameters

Since difficulty with respiration limits tolerance to transverse acceleration, the effect of this acceleration on different respiratory factors was tested in 15 subjects. Minute volume, respiratory rate, tidal volume, maximum breathing capacity, 0.5-second timed vital capacity and total vital capacity were measured at 3 and 5 g with the subject's trunk perpendicular to the centrifugal force and legs and knees flexed at 90 degrees. Vital capacity was reduced significantly at 3 and 5 g. Maximum breathing capacity was significantly reduced at 5 g. One-half-second timed vital capacity represented an increasing fraction of total vital capacity as acceleration increased. Minute volume and respiratory rate also increased significantly at 5 g while tidal volume was essentially unchanged. Results are obtained which indicate that the nature of the predominant respiratory defect during forward acceleration is restrictive. Of the respiratory parameters measured, vital capacity showed the greatest decrement. Submitted on April 17, 1959

Pulmonary function during norepinephrine-induced calorigenesis in cold-acclimatized rats

1963 ◽  
Vol 18 (6) ◽  
pp. 1213-1216 ◽  
Author(s):  
Eugene Evonuk ◽  
John P. Hannon
Keyword(s):  
Pulmonary Function ◽  
Tidal Volume ◽  
Respiratory Rate ◽  
Minute Volume ◽  
Oxygen Extraction ◽  
Cold Acclimatization ◽  
Infusion Of Norepinephrine

The effects of cold acclimatization on pulmonary function during norepinephrine-induced calorigenesis were studied. Norepinephrine resulted in a marked increase (85%) in the pulmonary minute volume in both the warm- and cold-acclimatized rats. This increase in the warm-acclimatized rats was accomplished entirely by increasing the respiratory rate, whereas in the cold-acclimatized rats, the increase in pulmonary minute volume was achieved for the most part by increasing the tidal volume with a slight increase in respiratory rate. Cold acclimatization was associated with a greater “efficiency of oxygen extraction” before, during, and after the infusion of norepinephrine. pulmonary minute volume; respiratory rate; oxygen extraction Submitted on December 6, 1962

STUDIES OF RESPIRATORY PHYSIOLOGY IN CHILDREN

PEDIATRICS ◽  
1959 ◽  
Vol 24 (2) ◽  
pp. 181-193
Author(s):  
C. D. Cook ◽  
P. J. Helliesen ◽  
L. Kulczycki ◽  
H. Barrie ◽  
L. Friedlander ◽  
...  
Keyword(s):  
Tidal Volume ◽  
Respiratory Rate ◽  
Vital Capacity ◽  
Total Lung Capacity ◽  
Lung Compliance ◽  
Respiratory Physiology ◽  
Residual Volume ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Residual Capacity

Tidal volume, respiratory rate and lung volumes have been measured in 64 patients with cystic fibrosis of the pancreas while lung compliance and resistance were measured in 42 of these. Serial studies of lung volumes were done in 43. Tidal volume was reduced and the respiratory rate increased only in the most severely ill patients. Excluding the three patients with lobectomies, residual volume and functional residual capacity were found to be significantly increased in 46 and 21%, respectively. These changes correlated well with the roentgenographic evaluation of emphysema. Vital capacity was significantly reduced in 34% while total lung capacity was, on the average, relatively unchanged. Seventy per cent of the 61 patients had a signficantly elevated RV/TLC ratio. Lung compliance was significantly reduced in only the most severely ill patients but resistance was significantly increased in 35% of the patients studied. The serial studies of lung volumes showed no consistent trends among the groups of patients in the period between studies. However, 10% of the surviving patients showed evidence of significant improvement while 15% deteriorated. [See Fig. 8. in Source Pdf.] Although there were individual discrepancies, there was a definite correlation between the clinical evaluation and tests of respiratory function, especially the changes in residual volume, the vital capacity, RV/ TLC ratio and the lung compliance and resistance.

scholarly journals Micron-sized intrapulmonary particle deposition in the developing rat lung

2012 ◽  
Vol 112 (5) ◽  
pp. 759-765
Author(s):  
Holger Schulz ◽  
Gunter Eder ◽  
Ines Bolle ◽  
Akira Tsuda ◽  
Stefan Karrasch
Keyword(s):  
Tidal Volume ◽  
Respiratory Rate ◽  
Surface Area ◽  
Lung Development ◽  
Particle Deposition ◽  
Structural Changes ◽  
Breathing Patterns ◽  
Respiratory Parameters ◽  
Wistar Kyoto ◽  
Postnatal Lung Development

Little is known about the effects of postnatal developmental changes in lung architecture and breathing patterns on intrapulmonary particle deposition. We measured deposition in the developing Wistar-Kyoto rat, whose lung development largely parallels that of humans. Deposition of 2-μm sebacate particles was determined in anesthetized, intubated, spontaneously breathing rats on postnatal days (P) 7 to 90 by aerosol photometry (Karrasch S, Eder G, Bolle I, Tsuda A, Schulz H. J Appl Physiol 107: 1293–1299, 2009). Respiratory parameters were determined by body plethysmography. Tidal volume increased substantially from P7 (0.19 ml) to P90 (2.1 ml) while respiratory rate declined from 182 to 107/min. Breath-specific deposition was lowest (9%) at P7 and P90 and markedly higher at P35 (almost 16%). Structural changes of the alveolar region include a ninefold increase in surface area (Bolle I, Eder G, Takenaka S, Ganguly K, Karrasch S, Zeller C, Neuner M, Kreyling WG, Tsuda A, Schulz H. J Appl Physiol 104: 1167–1176, 2008). Particle deposition per unit of time and surface area peaked at P35 and showed a minimum at P90. At an inhaled particle number concentration of 105/cm3, there was an estimated 450, 690, and 330 particles/(min × cm2) at P7, P35, and P90, respectively. Multiple regression models showed that deposition depends on the mean linear intercept as structural component and the breathing parameters, tidal volume, and respiratory rate ( r2 > 0.9). In conclusion, micron-sized particle deposition was dependent on the stage of postnatal lung development. A maximum was observed during late alveolarization (P35), which corresponds to human lungs of about eight years of age. Children at this age may therefore be more susceptible to micron-sized airborne environmental health hazards.

Ventilatory Responses to Exercise and to Carbon Dioxide in Mitral Stenosis before and after Valvulotomy: Causes of Tachypnoea

1978 ◽  
Vol 54 (1) ◽  
pp. 9-16 ◽  
Author(s):  
J. W. Reed ◽  
M. Ablett ◽  
J. E. Cotes
Keyword(s):  
Carbon Dioxide ◽  
Tidal Volume ◽  
Mitral Stenosis ◽  
Vital Capacity ◽  
Minute Ventilation ◽  
Residual Effect ◽  
Minute Volume ◽  
Cardiac Frequency ◽  
Control Subjects ◽  
Exercise Ventilation

1. The ventilation and cardiac frequency during progressive exercise and the respiratory responses to breathing carbon dioxide have been measured in 33 female patients with mitral stenosis and in 31 control subjects. Compared with the control subjects, the patients' exercise ventilation and cardiac frequency were increased; the exercise tidal volume at standard minute volume, the vital capacity and the ventilatory response to carbon dioxide were reduced. The extent to which the standardized tidal volume was lower during exercise than during breathing carbon dioxide was correlated with the severity of the stenosis, as gauged by the increase in exercise cardiac frequency above the level predicted from anthropometric measurements. 2. Twenty patients were studied postoperatively. In the 12 who showed clinical improvement the exercise ventilation and cardiac frequency were reduced and the exercise tidal volume at a given minute ventilation was increased. The latter change occurred despite a reduction in vital capacity, which was probably a residual effect of thoractomy. There was no significant change in the response to breathing carbon dioxide. No material change in function was observed in the patients whose condition was not improved by the operation. 3. It is suggested that in mitral stenosis the tachypnoea which occurs during exercise, whilst mainly a mechanical consequence of the reduced vital, capacity, is also partly due to pulmonary congestion stimulating intrapulmonary receptors.

scholarly journals Physiological respiratory parameters in pre-hospital patients with suspected COVID-19: A prospective cohort study

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0257018
Author(s):  
Johan Mälberg ◽  
Nermin Hadziosmanovic ◽  
David Smekal
Keyword(s):  
Logistic Regression ◽  
Hospital Admission ◽  
Tidal Volume ◽  
Respiratory Rate ◽  
Dead Space ◽  
Hospital Admissions ◽  
Rapid Shallow Breathing Index ◽  
Respiratory Parameters ◽  
Hospital Patients ◽  
Adjusted Logistic Regression

Background The COVID-19 pandemic has presented emergency medical services (EMS) worldwide with the difficult task of identifying patients with COVID-19 and predicting the severity of their illness. The aim of this study was to investigate whether physiological respiratory parameters in pre-hospital patients with COVID-19 differed from those without COVID-19 and if they could be used to aid EMS personnel in the prediction of illness severity. Methods Patients with suspected COVID-19 were included by EMS personnel in Uppsala, Sweden. A portable respiratory monitor based on pneumotachography was used to sample the included patient’s physiological respiratory parameters. A questionnaire with information about present symptoms and background data was completed. COVID-19 diagnoses and hospital admissions were gathered from the electronic medical record system. The physiological respiratory parameters of patients with and without COVID-19 were then analyzed using descriptive statistical analysis and logistic regression. Results Between May 2020 and January 2021, 95 patients were included, and their physiological respiratory parameters analyzed. Of these patients, 53 had COVID-19. Using adjusted logistic regression, the odds of having COVID-19 increased with respiratory rate (95% CI 1.000–1.118), tidal volume (95% CI 0.996–0.999) and negative inspiratory pressure (95% CI 1.017–1.152). Patients admitted to hospital had higher respiratory rates (p<0.001) and lower tidal volume (p = 0.010) compared to the patients who were not admitted. Using adjusted logistic regression, the odds of hospital admission increased with respiratory rate (95% CI 1.081–1.324), rapid shallow breathing index (95% CI 1.006–1.040) and dead space percentage of tidal volume (95% CI 1.027–1.159). Conclusion Patients taking smaller, faster breaths with less pressure had higher odds of having COVID-19 in this study. Smaller, faster breaths and higher dead space percentage also increased the odds of hospital admission. Physiological respiratory parameters could be a useful tool in detecting COVID-19 and predicting hospital admissions, although more research is needed.

Pulmonary Function Tests

2011 ◽  
pp. 108-121 ◽  
Author(s):  
James R. Munis
Keyword(s):  
Carbon Monoxide ◽  
Pulmonary Function ◽  
Tidal Volume ◽  
Flow Rate ◽  
Pulmonary Function Tests ◽  
Horizontal Axis ◽  
Arterial Blood Gas ◽  
Arterial Blood ◽  
Function Tests ◽  
Respiratory Parameters

Pulmonary function tests (PFTs) sort out the ability of the lungs to ventilate and oxygenate. Perhaps the most useful PFT measures arterial blood gas (ABG). Once we've established that the ABG is normal, it doesn't much matter whether pulmonary function is provided by a machine or is natural, nor do specific respiratory parameters (eg, tidal volume, respiratory rate, flow rate) matter as much as the end result of pulmonary function—the ABGs. The next type of PFT is spirometry, is the measurement of inhaled and exhaled lung gas. The next PFT is the flow-volume loop. Before looking at how the loop changes with pathologic conditions, you should be familiar with the axes of the graph. Note that the horizontal axis is inverted, with high volumes closer to the origin and low volumes further from the origin. Finally, the test measuring diffusing capacity of the lung for carbon monoxide (DLCO) rounds out the list of commonly used PFTs.

scholarly journals Mechanics of Respiration in Unanesthetized Guinea Pigs

1958 ◽  
Vol 192 (2) ◽  
pp. 364-368 ◽  
Author(s):  
Mary O. Amdur ◽  
Jere Mead
Keyword(s):  
Tidal Volume ◽  
Respiratory Rate ◽  
Experimental Animal ◽  
Respiratory System ◽  
Guinea Pigs ◽  
Flow Resistance ◽  
Minute Volume ◽  
Intrapleural Pressure ◽  
Pulmonary Flow ◽  
Volume Resistance

A technique has been described by which tidal volume, intrapleural pressure and rate of flow of gas in and out of the respiratory system can be measured simultaneously in unanesthetized guinea pigs for periods of several hours. These data permit the calculation of the pulmonary flow-resistance and compliance for an experimental animal with normal reflex behavior. The values obtained on 200 normal and 20 tracheotomized animals for tidal volume, respiratory rate, minute volume, resistance and compliance are given.

scholarly journals The efficacy of two-year yogic practice on selected pulmonary function test in postmenopausal women

Biomedicine ◽  
2020 ◽  
Vol 39 (2) ◽  
pp. 292-297
Author(s):  
Bhat Ramesh ◽  
Pratik Kumar Chatterjee ◽  
Budihal Suman Veerappa ◽  
Arun Kumar Nayanatara ◽  
Kunal . ◽  
...  
Keyword(s):  
Pulmonary Function ◽  
Postmenopausal Women ◽  
Vital Capacity ◽  
Control Group ◽  
Yoga Practice ◽  
Group I ◽  
Respiratory Parameters ◽  
Expiratory Flow ◽  
Group Ii ◽  
One Year

Introduction and Aim: Menopausal transition has been well associated with a series of hormonal changes that has been linked to impairment of respiratory function. The present study was designed to evaluate the cumulative effect of practicing yoga on certain respiratory parameters in postmenopausal women. Materials and Methods: Sixty postmenopausal women were divided into two groups (n=30 each). Based on the duration of yoga, they were grouped into Group I – (Regularly doing yoga for one year) and Group II (Regularly doing yoga for the two years). The women not doing any yogic exercises were taken as the control group; Group Ia (for One year) and Group II a (for two years). The respiratory parameters were measured with the help of vitalograph. Results: All the observed respiratory parameters such as vital capacity (VC), Forced vital capacity (FVC), FEV1 (Forced expiratory volume during the 1st second.), FEV1 ratio, PEFR (Peak expiratory flow rate). FEF50 (Forced Expiratory Flow at 50%), showed a significant (P<0.0001) improvement in Group II when compared to the Group I. Conclusion: Yoga practice can be advocated to improve pulmonary function tests in post-menopausal women which might help in preventing respiratory diseases during aging process. Optimum benefit of yoga was observed during the two years of yoga practice in the postmenopausal women. Continued practice of yoga might be also considered as a preventive exercise to impair age related morbidity and improve the quality of life.  

scholarly journals Function of the Dräger Oxylog Ventilator at High Altitude

1994 ◽  
Vol 22 (3) ◽  
pp. 276-280 ◽  
Author(s):  
G. Thomas ◽  
J. Brimacombe
Keyword(s):  
Tidal Volume ◽  
Respiratory Rate ◽  
High Altitude ◽  
Opposite Direction ◽  
Linear Increase ◽  
Minute Volume ◽  
Normal Lung ◽  
Lung Simulator ◽  
Sufficient Magnitude ◽  
Frequent Observation

We have assessed the performance of the Dräger Oxylog ventilator at high altitude using a decompression chamber and a lung simulator set to mimic the normal and non-compliant lung. In the normal lung, tidal volume increased by 28% at 2040 metres and by 106% at 9120 metres. A lesser change, but in the opposite direction, occurred in respiratory rate. The net effect was a linear increase in minute volume with altitude. At 2040 and 9144 metres minute volume increased by 13% and by 45%, and rate decreased by 10% and 30% respectively. In the abnormal lung stimulation, similar, but slightly less marked, changes occurred in all variables. These changes are of sufficient magnitude to require frequent observation of tidal volume and respiratory rate during aircraft ascent and descent.

scholarly journals Postoperative study of vital capacity and ventilation measurements following elective craniotomy

2008 ◽  
Vol 126 (1) ◽  
pp. 11-16 ◽  
Author(s):  
Luciana Carrupt Machado Sogame ◽  
Sonia Maria Faresin ◽  
Milena Carlos Vidotto ◽  
José Roberto Jardim
Keyword(s):  
Tidal Volume ◽  
Vital Capacity ◽  
Tumor Resection ◽  
Minute Volume ◽  
Respiratory Frequency ◽  
University Hospital ◽  
The Third ◽  
Aneurysm Clipping ◽  
Postoperative Study ◽  
Surgery Duration

CONTEXT AND OBJECTIVE: Changes in pulmonary function commonly occur after general surgery. The aims were to evaluate vital capacity, tidal volume and respiratory frequency among patients undergoing elective craniotomy and to determine possible correlations of these parameters with surgery duration and etiology for neurosurgery. DESIGN AND SETTING: Prospective, open study at a tertiary university hospital. METHODS: Twenty-six patients underwent elective craniotomy for aneurysm clipping (11) or tumor resection (15). Vital capacity (VC), tidal volume (TV), minute volume (VE) and respiratory rate were determined before the operation and on the first to fourth postoperative days. RESULTS: There were significant decreases of 25% in VC, 22% in TV and 12% in VE (p < 0.05) and no significant increase in respiratory frequency (5%) on the first postoperative day. VE returned to baseline on the second postoperative day and TV on the third postoperative day, while VC was 8% lower on the fourth postoperative day, compared with before the operation (p < 0.05). VC reduction was significantly greater in patients undergoing aneurysm clipping (43%) than in patients undergoing tumor resection (14%) when surgery duration was more than four hours (p < 0.05), with no significant change when surgery duration was less than four hours. CONCLUSION: Reductions in VC, TV and VE were observed during the postoperative period in patients undergoing aneurysm clipping or tumor resection. The reductions in VC and TV were greater in patients undergoing craniotomy due to aneurysm and with longer surgery duration.

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