Changes in the Nasal NO Level, Nasal Resistance, and Nasal Patency before and after Exercise in Normal Subjects

Background Past studies reported a low correlation between rhinomanometry and computational fluid dynamics (CFD), but the source of the discrepancy was unclear. Low correlation or lack of correlation has also been reported between subjective and objective measures of nasal patency. Objective: This study investigates (1) the correlation and agreement between nasal resistance derived from CFD (RCFD) and rhinomanometry (RRMN), and (2) the correlation between objective and subjective measures of nasal patency. Methods Twenty-five patients with nasal obstruction underwent anterior rhinomanometry before and after mucosal decongestion with oxymetazoline. Subjective nasal patency was assessed with a 0-10 visual analog scale (VAS). CFD simulations were performed based on computed tomography scans obtained after mucosal decongestion. To validate the CFD methods, nasal resistance was measured in vitro (REXPERIMENT) by performing pressure-flow experiments in anatomically accurate plastic nasal replicas from 6 individuals. Results Mucosal decongestion was associated with a reduction in bilateral nasal resistance (0.34 ± 0.23 Pa.s/ml to 0.19 ± 0.24 Pa.s/ml, p = 0.003) and improved sensation of nasal airflow (bilateral VAS decreased from 5.2 ± 1.9 to 2.6 ± 1.9, p < 0.001). A statistically significant correlation was found between VAS in the most obstructed cavity and unilateral airflow before and after mucosal decongestion (r = −0.42, p = 0.003). Excellent correlation was found between RCFD and REXPERIMENT (r = 0.96, p < 0.001) with good agreement between the numerical and in vitro values (RCFD/REXPERIMENT = 0.93 ± 0.08). A weak correlation was found between RCFD and RRMN (r = 0.41, p = 0.003) with CFD underpredicting nasal resistance derived from rhinomanometry (RCFD/RRMN = 0.65 ± 0.63). A stronger correlation was found when unilateral airflow at a pressure drop of 75 Pa was used to compare CFD with rhinomanometry (r = 0.76, p < 0.001). Conclusion CFD and rhinomanometry are moderately correlated, but CFD underpredicts nasal resistance measured in vivo due in part to the assumption of rigid nasal walls. Our results confirm previous reports that subjective nasal patency correlates better with unilateral than with bilateral measurements and in the context of an intervention.

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Alae nasi activation decreases nasal resistance during hyperoxic hypercapnia

Journal of Applied Physiology ◽

10.1152/jappl.1998.85.1.294 ◽

1998 ◽

Vol 85 (1) ◽

pp. 294-300 ◽

Cited By ~ 7

Author(s):

Yong-Xin Shi ◽

Margaret Seto-Poon ◽

John R. Wheatley

Keyword(s):

Nasal Cavity ◽

Muscle Activity ◽

Normal Subjects ◽

Nasal Passage ◽

Nasal Resistance ◽

Nasal Vestibule ◽

Nasal Decongestant ◽

Linear Relationships ◽

Before And After

It has been proposed that decreases in nasal resistance (Rn) during hypercapnia are entirely due to vasoconstriction in the nasal cavity. We hypothesized that alae nasi (AN) muscle activity dilates the nasal vestibule and contributes to the decrease in Rn during hypercapnia. Nine normal subjects were studied during hyperoxic hypercapnia (HH). Rn and vestibular resistance (Rvest) for one nasal passage were measured simultaneously with the AN electromyogram before and after nasal decongestion. HH decreased Rvest from 1.6 ± 0.6 to 0.8 ± 0.9 cmH2O ⋅ l−1 ⋅ s (predecongestant) and from 1.3 ± 0.8 to 0.6 ± 0.7 cmH2O ⋅ l−1 ⋅ s (postdecongestant; both P < 0.01). Nasal decongestant decreased Rn but not Rvest. Significant inverse linear relationships between Rvest and AN electromyogram were demonstrated for all subjects. We conclude that in normal subjects during HH 1) decreases in Rvest are predominantly due to increases in AN activity; and 2) decreases in Rn are due to a combination of mucosal vasoconstriction and AN activation.

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The acute impact of continuous positive airway pressure on nasal resistance: a randomized controlled comparison

Journal of Applied Physiology ◽

10.1152/japplphysiol.00639.2006 ◽

2007 ◽

Vol 102 (3) ◽

pp. 1214-1219 ◽

Cited By ~ 4

Author(s):

Stephanie Willing ◽

Maybelle San Pedro ◽

Helen S. Driver ◽

Peter Munt ◽

Michael F. Fitzpatrick

Keyword(s):

Continuous Positive Airway Pressure ◽

Airway Pressure ◽

Positive Airway Pressure ◽

Normal Subjects ◽

Acute Effect ◽

Nasal Symptom ◽

Nasal Resistance ◽

Randomized Controlled ◽

Before And After ◽

Peak Nasal Inspiratory Flow

Subjective nasal obstruction is common among users of continuous positive airway pressure (CPAP). The aim of this study was to measure the acute effect of CPAP on nasal resistance and nasal symptoms in awake normal subjects. Twenty-four healthy CPAP-naive adults [8 men, 16 women; mean age 30 yr (SD 14)] underwent a randomized controlled crossover study comparing nasal CPAP (8 cmH2O) for 6 h on one occasion and the control condition (nasal mask without CPAP) on the other. Nasal resistance measurements (posterior active rhinometry) before and after the test exposure were similar on both test days. Nasal resistance during CPAP exposure [2.04 cmH2O·l−1·s (SD 0.72)] was significantly lower than that of the control [2.67 cmH2O·l−1·s (SD 1.07)]: mean difference 0.66 cmH2O·l−1·s, 95% confidence interval 0.19–1.13 cmH2O·l−1·s. The gradient in pressure from CPAP mask to posterior naris during CPAP exposure varied from 1.6 to 2 cmH2O but was not significantly different between time points. Subjective nasal symptom scores and peak nasal inspiratory flow rates did not change significantly on either test day. We conclude that in awake CPAP-naive normal subjects, acute CPAP exposure is associated with a reduction in nasal resistance compared with the control condition, but it is not associated with an immediate post-CPAP change in subjective or objective nasal resistance.

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Nasal resistance asymmetry as a predictor of satisfaction following nasal airway obstruction surgeries

Polski Przegląd Otorynolaryngologiczny ◽

10.5604/01.3001.0010.7498 ◽

2017 ◽

Vol 6 (4) ◽

pp. 1-9

Author(s):

Monika Prus ◽

Jarosław Wysocki ◽

Marta Krasny ◽

Kazimierz Niemczyk

Keyword(s):

Airway Obstruction ◽

Subjective Assessment ◽

Subjective Perception ◽

Nasal Airway ◽

Nasal Resistance ◽

Nasal Patency ◽

Self Evaluation ◽

Before And After ◽

The Right ◽

Medical University

Patients’ subjective assessment of nasal patency often does not correspond to the objective results of functional and imaging examinations. The objective of this study was to identify the rhinometry (AR) and rhinomanometry (RMM) parameters that were best correlated to patients’ self-evaluation of nasal patency before and after nasal airway obstruction surgery. The study material consisted of RMM and AR results as well as SNOT-20 self-evaluation questionnaires completed by 233 patients presenting with rhinological problems and routinely diagnosed at the RMM Lab of the Department and Clinic of Otolaryngology of the Medical University of Warsaw. Data were collected from 70 females (31.4%) aged 18 through 81 years and 153 males (68.6%) aged 16 through 81 years. The results were subjected to statistical analysis by a licensed statistician using the Statistica 10 software package. A statistically significant relationship was demonstrated between the subjective perception of nasal patency and RMM results. The higher the asymmetry of air flow within the left and the right nasal cavity, the higher the perceived restriction of nasal patency. Significant differences were observed between patients reporting maximum discomfort regarding impaired nasal patency and the remaining patients: the former were characterized by nasal resistance values being several-fold higher than that observed in the latter while nearly always improving after nasal airway obstruction surgeries. No significant reflection of patients’ self-evaluation of nasal patency was found in the acoustic rhinometry measurements.

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The Effect of Stapedectomy on the Loudness of One’s Own Voice

Journal of Speech and Hearing Research ◽

10.1044/jshr.0803.223 ◽

1965 ◽

Vol 8 (3) ◽

pp. 223-234 ◽

Cited By ~ 1

Author(s):

William Melnick

Keyword(s):

Middle Ear ◽

Normal Subjects ◽

Sound Energy ◽

Loudness Function ◽

Before And After ◽

Increased Sensitivity

Five subjects with normal middle ear mechanisms, and otosclerotic patients, before and after stapedectomy, matched the loudness of their voices to the loudness of a 125-cps-sawtooth noise. The results showed loudness matching functions with gradual slopes, less than 1.00, for the normal subjects and the patients prior to stapedectomy. Post-surgically, the loudness function for the patients increased in steepness to considerably more than 1.00. These results are explained, most logically, in terms of increased sensitivity of the altered middle ear to sound energy generated by the listener’s own voice.

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BESTIMMUNG DER INSULINAKTIVITÄT IM MENSCHLICHEM SERUM NACH GLUKOSEBELASTUNG ALS PRÜFUNG DER FUNKTIONSFÄHIGKEIT DES PANKREAS

Acta Endocrinologica ◽

10.1530/acta.0.0420437 ◽

1963 ◽

Vol 42 (3) ◽

pp. 437-452 ◽

Cited By ~ 8

Author(s):

H. Daweke

Keyword(s):

Blood Sugar ◽

Pancreatic Insufficiency ◽

Normal Subjects ◽

Insulin Binding ◽

Epididymal Adipose Tissue ◽

Moderate Increase ◽

Glucose Loading ◽

Before And After ◽

Oral Hypoglycaemic Drugs ◽

Severity Of The Disease

Using the method of glucose-1-14C oxydation to 14CO2 on the rat epididymal adipose tissue, the insulin-like activities (ILA) in the serum have been compared before and after oral loading with glucose in normal subjects, in maturity-onset diabetics and in insulin-requiring diabetics. In maturity-onset diabetics mean fasting values were found to be 30% below normal while in insulin-requiring diabetics they were 85% above normal. In normal subjects there was observed, 30 minutes after glucose loading, a moderate increase in blood sugar together with an increase of ILA of 222% above the starting value; in maturity-onset diabetics the increase in ILA was only 106% while the blood sugar was markedly increased. After glucose loading in maturity-onset diabetics, the total amount of insulin detected during the period of the experiment was, on the average, only 45% of that found in normal subjects. In insulin requiring diabetics there was no increase but, on the contrary, a steady decrease of the ILA values, while the blood sugar excessively increased. In general ILA values were higher than those in maturity-onset diabetics. No difference in response was found between maturity-onset diabetics treated with diet alone and those treated with diet and oral hypoglycaemic drugs. In contrast to the absolute ILA values, the index of insulin reserve, is of value in assessing the functional capacity of the pancreas. This index decreases progressively with the severity of the disease and reaches a maximum of 54% of the normal in maturity-onset diabetics, which can satisfactorily be explained by pancreas insufficiency. Only in some cases of insulin-requiring diabetics was an insulin reserve still detectable. The biological inactivity of the insulin circulating in the blood can be deduced from the increased ILA-values, as compared with those found in maturity-onset diabetics. Obviously some of this insulin can be released by the addition of glucose. It is likely that, in addition to pancreatic insufficiency, insulin-binding or insulin-inactivating antibodies play a part in the pathogenesis of insulin-requiring diabetes.

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DETERMINATION OF BLOOD CORTICOIDS USING THE IN VITRO RESIN UPTAKE OF 3H-PREDNISOLONE

Acta Endocrinologica ◽

10.1530/acta.0.0570023 ◽

1968 ◽

Vol 57 (1) ◽

pp. 23-32 ◽

Cited By ~ 2

Author(s):

Hironori Nakajima ◽

Mitsunori Murala ◽

Masumitsu Nakata ◽

Takeshi Naruse ◽

Seiji Kubo

Keyword(s):

Thyroid Function Test ◽

Normal Subjects ◽

Adrenal Function ◽

Function Test ◽

Before And After ◽

Adrenal Response ◽

Suppression Test

ABSTRACT The in vitro resin uptake of 3H-prednisolone was used for the determination of blood cortisol after addition of radioactive prednisolone followed by Amberlite CG 400 Type 1 to the test serum, and incubation of the mixture. The radioactivity of the supernatant was compared before and after the addition of the resin. The principle of this method is similar to that of the 131I-triiodothyronine resin uptake for the thyroid function test. The tests for the specificity, reproducibility and sensitivity gave satisfactory results. The mean basal value ± SD of the 3H-prednisolone resin uptake was 35.3 ± 9.2% in normal subjects, and 27.1 ± 4.8% in pregnant women. This method was valid in various adrenal function tests, i. e. the adrenal circadian rhythm, corticotrophin (ACTH) test, dexamethasone suppression test and the adrenal response to lysine-8-vasopressin. It proved to be a sensitive indicator of the adrenal function. These results suggest that this method should be useful for a routine adrenal function test.

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Effects of adaptation of vestibulo-ocular reflex function on manual target localization

Journal of Vestibular Research ◽

10.3233/ves-2000-10202 ◽

2000 ◽

Vol 10 (2) ◽

pp. 75-86 ◽

Cited By ~ 1

Author(s):

Jacob J. Bloomberg ◽

Lauren A. Merkle ◽

Susan R. Barry ◽

William P. Huebner ◽

Helen S. Cohen ◽

...

Keyword(s):

Adaptive Modulation ◽

Normal Subjects ◽

Target Localization ◽

Whole Body ◽

Spatial Coding ◽

Ocular Reflex ◽

Manual Responses ◽

Vestibular Cues ◽

Before And After ◽

Vestibulo Ocular Reflex

The goal of the present study was to determine if adaptive modulation of vestibulo-ocular reflex (VOR) function is associated with commensurate alterations in manual target localization. To measure the effects of adapted VOR on manual responses we developed the Vestibular-Contingent Pointing Test (VCP). In the VCP test, subjects pointed to a remembered target following passive whole body rotation in the dark. In the first experiment, subjects performed VCP before and after wearing 0.5X minifying lenses that adaptively attenuate horizontal VOR gain. Results showed that adaptive reduction in horizontal VOR gain was accompanied by a commensurate change in VCP performance. In the second experiment, bilaterally labyrinthine deficient (LD) subjects were tested to confirm that vestibular cues were central to the spatial coding of both eye and hand movements during VCP. LD subjects performed significantly worse than normal subjects. These results demonstrate that adaptive change in VOR can lead to alterations in manual target localization.

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Pressor responses to norepinephrine in humans before and after corticosteroids

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1962.203.5.961 ◽

1962 ◽

Vol 203 (5) ◽

pp. 961-963 ◽

Cited By ~ 32

Author(s):

Mohinder P. Sambhi ◽

Max H. Weil ◽

Vasant N. Udhoji

Keyword(s):

Human Subject ◽

Normal Subjects ◽

Adrenal Function ◽

Variance Analysis ◽

Acute Administration ◽

Intravenous Injections ◽

Pressor Responses ◽

Before And After

Pressor responses produced by intravenous injections of graded doses of norepinephrine were recorded in ten normal subjects before and after pharmacologic doses of glucocorticoids. Two subjects had been pretreated with 9α-fluorocortisol. Although a considerable variation was found in the responsiveness to repeated norepinephrine injections, variance analysis demonstrated that administration of adrenal cortical hormones and their analogues did not significantly alter the response. These observations do not support the hypothesis that acute administration of corticosteroids in large doses potentiates the pressor effects of catecholamines in the human subject with normal adrenal function.

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Near-maximal voluntary hyperpnea and ventilatory muscle function

Journal of Applied Physiology ◽

10.1152/jappl.1984.57.6.1742 ◽

1984 ◽

Vol 57 (6) ◽

pp. 1742-1748 ◽

Cited By ~ 31

Author(s):

T. R. Bai ◽

B. J. Rabinovitch ◽

R. L. Pardy

Keyword(s):

Muscle Function ◽

Low Frequency ◽

Normal Subjects ◽

Pressure Time ◽

Before And After ◽

Expiratory Muscles ◽

Four Levels ◽

Frequency Relationship ◽

Low Frequency Power ◽

Relationship Of

Because of its potential relevance to heavy exercise we studied the ventilatory muscle function of five normal subjects before, during, and after shortterm near-maximal voluntary normocapnic hyperpnea. Measurements of pleural and abdominal pressures and diaphragm electromyogram (EMG) during hyperpnea and of maximum respiratory pressures before and after hyperpnea were made at four levels of ventilation: 76, 79, and 86% maximal voluntary ventilation (MVV) and at MVV. Measurements of pleural and abdominal pressures and diaphragm electromyogram (EMG) during hyperpnea and of maximum respiratory pressures before and after hyperpnea were made. The pressure-stimulation frequency relationship of the diaphragm obtained by unilateral transcutaneous phrenic nerve stimulation was studied in two subjects before and after hyperpnea. Decreases in maximal inspiratory (PImax) and transdiaphragmatic (Pdimax) strength were recorded posthyperpnea at 76 and 79% MVV. Decreases in the pressure-frequency curves of the diaphragm and the ratio of high-to-low frequency power of the diaphragm EMG occurred in association with decreases in Pdimax. Analysis of the pressure-time product (P X dt) for the inspiratory and expiratory muscles individually indicated the increasing contribution of expiratory muscle force to the attainment of higher levels of ventilation. Demonstrable ventilatory muscle fatigue may limit endurance at high levels of ventilation.

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