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At least 19 recordsLinked to original sources
PubMed1992

Oscillometry of radial artery in acrocyanosis and cold sensitivity.

Acrocyanosis is reassessed on the basis of 34 new patients with diagnostic clinical features. The most useful tests are the skin temperature differences (STD) between wrist and end of fingers (or ankle and end of toes) and oscillometry over the radial and dorsalis pedis and posterior tibial arteries. Capillaroscopy of the conjunctival and nailfold vessels is useful in half the patients. Capillary resistance was not helpful. STD of 1.5 degrees C or more between skin of wrist or ankle and fingertip or toetip, is usually associated with more severe disease and capillary abnormalities on microscopy, and with reduced oscillometry (to 1 or less) over the radial arteries and dorsalis pedis and posterior tibial arteries. Reduced oscillometry is more associated with abnormalities than the other tests, and more than STD. The work of Mulvany and his colleagues suggests an explanation for the low oscillometry. Larger vessels than the arterioles and digital vessels can become resistance vessels in various circumstances. It is likely that the radial artery and vessels of similar diameter can temporarily act as resistance vessels in patients with acrocyanosis in a low temperature environment.

Adolescent↗
PubMed1990

[Lung function diagnosis using multi-frequency oscillometry with reference to lung volume].

The ranking of various oscillometry parameters was to be tested in patients with a broad spectrum of disturbances of pulmonary function, objectified by body plethysmographic and technical oesophageal pressure measurement of the respiratory resistance, lung volumes and lung elasticity. For this purpose the oscillatory resistance Rfo and the phase angle phi were measured at 8, 12 and 16Hz and phi was measured as it changed, depending on the lung volume V. It was found that enhanced respiratory resistance values are satisfactorily represented by Rfo for the purposes of preliminary and basic diagnostics. Besides, enhanced Rfo values are markedly dependent on the frequency, phi being shifted to negative values. Difference between Rfo values at 8 and 16 Hz (delta R8-16) less than 0.7 hPa/l/s phi greater than or equal to -10 degrees can be considered as being still normal with the employed measuring principle and are a valuable supplement for assessing the degree of obstruction. The difference between phi in the medium respiratory position and at 90 or 100% total capacity (delta phi) is less than 5 degrees during slow inspiration in 80% of the patients suffering from emphysema. In 80% of the persons with healthy lungs and those suffering from fibrosis there is an inspiratory negativation of phi (delta phi greater than 5 degrees) so that the phi-V relationship appear suitable for distinguishing patients with restricted vital capacity in respect of emphysema and fibrosis. Patients suffering fron fibrosis differ from healthy subjects by slightly more negative phi values. The borderline values for delta R8-16, phi and delta phi were confirmed in two further series of examinations on children and adolescents.

Adult↗
PubMed1991

Blood pressure changes associated with tilting in normotensive subjects: differences in response pattern as measured by oscillometry and auscultation.

Three non-invasive instruments were used to measure blood pressure in the supine position and on tilting--a conventional and a random-zero sphygmomanometer, and an oscillometric device (Accutorr 1A). Twenty normotensives volunteered for the study. There was no statistically significant difference in systolic blood pressure and diastolic blood pressure measured by the conventional and random-zero sphygmomanometers in the supine position. There was a difference between these recordings and those of the Accutorr, with the Accutorr giving higher readings of systolic blood pressure (p less than 0.001), analysis of variance, 95% confidence interval of the difference between the Accutorr and the random-zero was 5.1-15.7 mmHg) and lower readings of diastolic blood pressure (p less than 0.0001, analysis of variance, 95% confidence interval of the difference between the Accutorr and the random-zero was -12.2- -2.2 mmHg). On tilting, the Accutorr showed an increase in systolic blood pressure while the other two machines did not (p less than 0.01, analysis of variance). By contrast, the Accutorr detected a smaller rise in diastolic blood pressure than with the other two instruments (p less than 0.05, analysis of variance). The difference between blood pressure measurements made in the supine position by the two different techniques, auscultation and oscillometry, might be expected. However, the two different techniques do not detect the same blood pressure responses to a change in posture.

Adult↗
PubMedDate not supplied

[Oscillometry on various stape protheses. Experimental examination of human temporal bone preparations].

In human temporal bone specimens the vibrations of the labyrinthine fluid were measured by a piezoelectric system after application of various techniques of otosclerosis surgery. Compared with the amplitude in the case of a normal stapes, the surgical techniques according to Zangemeister, Shea and Schuknect resulted in considerable transmission losses in the high frequency range, while transmission of low frequencies to the inner ear was almost equivalent to normal transmission via the stapes. For frequencies of more than 3,000 Hertz the damping influence of the fibrous tissue implanted into the oval window was verified. The results of surgery according to Zangemeister, Shea and Schuknechtdid not differ significantly in the low and medium frequency range. Only a Robinson prosthesis implanted like a Teflon piston caused an impairment of transmission, while the method of fitting this prosthesis onto fibrous tissue was equilvalent to the other techniques.

Ear, Middle↗
PubMed1990

[Effect of physical stress on airway resistance determined by oscillometry].

For evaluation of reference values of airway resistance measured by forced oscillation technique (Ros) in connection with physical exercise, 193 healthy persons were examined. In this study could be shown that reference values measured at rest are also valid under exercise conditions to find out functional disorders.

Adolescent↗
PubMed1989

[Optimizing monofrequent oscillometry].

Against the background of the working hypothesis of the 1-parametric Siregnost FD 5 forced oscillation technique-phase angle psi may be invariant in a clinical reference population-the hypothetical straight Ros-P line is in good agreement with the crowd of extremely nonlinear Rre-P-lines only within narrow limits. Neglecting phase angle measurements it might be useful to insert a known linear resistor into the airway to determine the pertaining Rre-P relation. In spite of selective tuning to the oscillation frequency of 10 Hz there is full sensitivity to stationary flow; alinear stationary flow characteristics of resistors can be readily determined by forced oscillation. There is a marked improvement in the P-psi/Rre-phi-evaluating system with respect both to the symmetry of phase angle and unequivocality of pressure when the reference phase angle alpha is shifted from 81 degrees to 0 degrees. Using digital data acquisition and processing, a flexible evaluation technique with monitor-oriented test management, automatical calculation of secondary values and multidimensional presentation of results on a graphical display is provided, which has proved its worth in experimental and clinical-physiological studies.

Airway Resistance↗
PubMed1989

[Polyfrequent oscillometry measurement of airway resistance including the associated phase angle].

In 52 subjects aged between 28 and 80 years (healthy subjects, patients with obstructive and restrictive pulmonary disease), the airway resistance including the associated phase angle was investigated employing the forced oscillation technique at various frequencies (8, 12 and 16 Hz). Measurements were performed using a device manufactured by the firm of Custo, which makes possible the direct determination of oscillatory pressure and alternating flow at the mouth. With the aid of the phase angle, the airway resistance Rfo was calculated in approximation on the basis of the recorded impedance. As a reference unit, a body plethysmograph manufactured by the firm of Jaeger was employed. The short-term intra-individual variability of the oscillatory resistance measurements was, at 15%, within the fluctuation range of Rtot. The best agreement of Rfo and Rtot was achieved at 8 Hz (r = 0.83). With increasing frequency, the correlation decreased appreciably. Even in the presence of normal Rfo, negative phase angles indicated a disturbance of the mechanics of respiration. In comparison with the oscillatory resistance the determination with a bridge circuit, the reference values measured were compatible with those obtained with whole-body plethysmography. Direct measurement of Rfo and the associated phase angle, compares favourably with the reference tube technique in terms of the lack of complexity of the apparatus and a reduction in operator effort, and is thus a measuring system that is suitable for use in the doctor's office.

Adult↗
PubMed1990

Accuracy of four indirect methods of blood pressure measurement, with hemodynamic correlations.

In 38 adults undergoing cardiac surgery, 4 indirect blood pressure techniques were compared with brachial arterial blood pressure at predetermined intervals before and after cardiopulmonary bypass. Indirect blood pressure measurement techniques included automated oscillometry, manual auscultation, visual onset of oscillation (flicker) and return-to-flow methods. Hemodynamic measurements or calculations included heart rate, cardiac index, stroke volume index, and systemic vascular resistance index. Indirect and intraarterial blood pressure values were compared by simple linear regression by patient and measurement period. Measurement errors (arterial minus indirect blood pressure) were calculated, and stepwise regression assessed the relationship between measurement error and heart rate, cardiac index, stroke volume index, and systemic vascular resistance index. Indirect to intraarterial blood pressure correlation coefficients varied over time, with the strongest correlations often occurring at the first and last measurement periods (preinduction and 60 minutes after cardiopulmonary bypass), particularly for systolic blood pressure. Within-patient correlations between indirect and arterial blood pressure varied widely--they were consistently high or low in some patients. In other patients, correlations were especially weak with a particular indirect blood pressure method for systolic, mean, or diastolic blood pressure; in some cases indirect blood pressure was inadequate for clinical diagnosis of acute blood pressure changes or trends. The mean correlations between indirect and direct blood pressure values were, for systolic blood pressure: 0.69 for oscillometry, 0.77 for auscultation, 0.73 for flicker, and 0.74 for return-to-flow; for mean blood pressure: 0.70 for oscillometry and 0.73 for auscultation; and for diastolic blood pressure: 0.73 for oscillometry and 0.69 for auscultation. The mean measurement errors (arterial minus indirect values) for the individual indirect blood pressure methods were, for systolic: 0 mm Hg for oscillometry, 9 mm Hg for auscultation, -5 mm Hg for flicker, 7 mm Hg for return-to-flow; for mean: -6 mm Hg for oscillometry, and -3 mm Hg for auscultation; and for diastolic: -9 mm Hg for oscillometry and -8 mm Hg for auscultation. Mean measurement error for systolic blood pressure was thus least with automated oscillometry and greatest with manual auscultation, while standard deviations ranging from 9 to 15 mm Hg confirmed the highly variable nature of single indirect blood pressure measurements. Except for oscillometric diastolic blood pressure, a combination of systemic hemodynamics (heart rate, stroke volume index, systemic vascular resistance index, and cardiac index) correlated with each indirect blood pressure measurement error, which suggests that particular numeric ranges of these variables minimize measurement error.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMedDate not supplied

[Determination of the steno-occlusive degree using non-invasive methods in diabetic patients with peripheral arterial insufficiency].

58 diabetic patients with peripheric arteriopathy are studied by means of segmentary pressure and oscillometry. Best results for proximal levels were those obtained with segmentary pressure index, whereas oscillometry was better for distal level (ankle and foot). The application of these criteria would facilitate the detection of arterial occlusions without need arteriography.

Aged↗
PubMed1979

Treatment and sequelae of angiographic complications in children.

Fourteen cases of thromboembolic complications appeared in 267 consecutive angiographies during a 7-yr period. The arterial circulation has been evaluated both clinically and with oscillometry. The complication rate was substantially higher after cut down then after percutaneous approach (56% vs. 2.7%). Seven patients with signs of total vascular obstruction were subjected to acute thromboectomy whereas three patients with milder clinical symptoms were treated nonoperatively with anticoagulants. Four patients have died during the examination period, the remaining ten patients have been subjected to long term follow-up (mean follow-up period 3 yr). Seven demonstrated normal findings clinically, as well as oscillographically, whereas three patients subjected ot thromboectomy after cut down were clinically normal but decreased oscillographic pulsations could be demonstrated.

Adolescent↗
PubMed1990

Comparison of oscillation with three other methods for measuring nasal airways resistance.

In this study we have compared the sensitivity and reproducibility of nasal airways resistance measurements made using an oscillometer, with those made by passive anterior, active anterior and active posterior rhinomanometry. Nasal airways resistance values were compared in 12 patients with rhinitis and 15 normal subjects, of whom ten had additional measurements after a vasoconstrictor spray, oxymetazoline. The coefficients of variation of 6-8 technically satisfactory measurements were 9-19%. The decongestant effect of oxymetazoline was detected by all methods, with no decrease in reproducibility. Post vasoconstrictor nasal airways resistance fell by 28% (passive anterior), 35% (active anterior), 36% (active posterior) and 58% (oscillometry). In conclusion, the oscillation method for deriving nasal airways resistance is a useful, new, simple and noninvasive way of assessing nasal airways patency. Results compare favourably with other, more established techniques.

Adult↗
PubMed1992

Oscillatory mechanics of the respiratory system in neuromuscular disease.

Respiratory impedance measurements by means of the technique of forced oscillations together with spirometry and measurements of maximal mouth pressures were performed in 27 patients with a variety of neuromuscular disorders to assess the value of adding respiratory impedance measurements in the evaluation of lung function in neuromuscular disease. Using the technique of forced oscillations, impedance measurements are easily performed in physically disabled persons, since they require little active cooperation and no forced respiratory maneuvers. Normal respiratory impedance characteristics were found, although resistance values were somewhat higher than those found in normal subjects, signifying the absence of airflow limitation. Spirometric values were markedly reduced, as were maximal mouth pressures. No significant correlations were found between the forced expiratory volumes in 1 s (FEV1) and the impedance data. A strong curvilinear relationship was observed between Pemax and the RV/TLC ratio and a strong correlation existed between FEV1 and Premax. It is concluded from our study that forced oscillometry is a useful tool for the assessment or exclusion of airflow obstruction in patients with neuromuscular disorders when plethysmography is difficult to perform and forced expiratory flow-volume data reflect muscle weakness rather than airflow limitation.

Adolescent↗
PubMed1992

[Blood pressure measurement using the fingers].

An increasing number of devices for self-assessment of blood pressure has been developed over the past years. Accepted international standards for evaluation of such devices are still lacking. A new apparatus (T88, Marshall Electronics) measuring blood pressure on digital arteries by oscillometry was tested for accuracy. Comparative measurements in 36 patients indicated position-dependent results with a reasonable correlation with the measurements taken on the upper arm only if the device was used at the level of the heart. Significant differences for systolic values were noted on different phalanges. In a last series of measurements, comparing values obtained about the basal phalanges of the index positioned at the level of the heart, significant differences were found for systolic and diastolic values compared to the traditional measurement. The use of this device for evaluation of hypertension, monitoring of treatment or use in studies is thus not recommended.

Arteries↗
PubMed1991

[The variability of arterial pressure measured by oscillometric methods in premature newborn infants].

The variability of blood pressure measured by oscillometry and the validity of this technique were studied in premature infants. Thirty premature babies whose postnatal age was six days or more had their blood pressure measured 11 times over a twenty-minute period for three consecutive days. Movements were found to have a very substantial influence on results that could not be reliably compared with values obtained invasively. No consistent pattern of variations of oscillometric results obtained during the eleven measurements of use for recommending a specific measurement time was found. Diastolic blood pressure fell gradually over the three-day study period. The most reliable of the eleven daily values was the lowest value for which good correlations were found between the three study days; this lowest value was not influenced by neonatal or postnatal factors.

Analysis of Variance↗
PubMed1990

Cardiovascular effects of caffeine therapy in preterm infants.

Theophylline therapy increases left ventricular output in preterm infants by a combination of positive inotropic and chronotropic effects. The cardiovascular effects of caffeine were evaluated in 20 clinically stable preterm infants. Ten infants received intravenous caffeine citrate with a loading dose of 20 mg/kg and a maintenance dose of 5 mg/kg every 24 hours, and 10 infants were control subjects. Left ventricular output, stroke volume, and heart rate were measured by using a combination of two-dimensional and pulsed Doppler echocardiography and mean arterial blood pressure by oscillometry (Dinamap, Critikon, Division of McNeil Laboratories, Irvine, Calif) before the start and on days 1, 2, 3, and 7 of caffeine therapy and 7 days after discontinuation of therapy. Compared with controls, left ventricular output and stroke volume were significantly increased on days 1 to 7 of caffeine therapy. Caffeine led to an increase in the mean arterial blood pressure on the first 3 days of therapy, but the heart rate did not change. These data indicated that caffeine administration leads to a significant increase in left ventricular output in preterm infants and that this inotropic effect is accompanied by a pressor effect.

Apnea↗
PubMed1979

Influence of thyroid surgery on voice function and laryngeal symptoms.

A comprehensive examination of voice function and laryngeal symptoms was applied systematically to 20 patients undergoing thyroid surgery. Patients were excluded from the series if there had been previous neck surgery or if postoperative indirect laryngoscopy showed abnormal cord mobility. Examination before operation showed that patients with sporadic non-toxic goitre or medically pre-treated toxic goitre had impaired voice function based on stroboscopy, electro-glottography, phono-oscillometry and determination of voice range, phonation time, pitch, and peak flow. Three months after thyroid surgery the voice function was significantly improved although not normal in non-toxic goitre patients, whereas the voice function in patients with thyrotoxicosis was unchanged. The number of laryngeal symptoms was significantly reduced in non-toxic goitres following surgery and unaltered in the group with thyrotoxicosis.

Adolescent↗
PubMedDate not supplied

The bronchodilator effect of a fixed-combination metered aerosol (fenoterol and ipratropium bromide).

The fixed-combination metered aerosol lK6 (fenoterol 0.05 mg/puff, ipratropium bromide 0.02 mg/puff--Berodual, Boehringer-Ingelheim Ltd., Ridgefield, Conn.) was administered to 12 children (8 boys, 4 girls) aged 3 1/2 to 6 2/12 years who had extrinsic bronchial asthma. Three forms of administration, each with a different site of action, were compared: Two puffs during inspiration. Probable site of action: oral cavity, pharynx, larynx, trachea, and bronchi. Two puffs using an inhalational aid during inspiration. Probable site of action: pharynx, larynx, trachea, and bronchi. Two puffs in the breathing interval after deep inspiration. Probable site of action: oral cavity and pharynx. The resistance of the respiratory system (Rrs) was measured using oscillometry for up to 360 minutes after administration. A significant decrease of the median resistance was found with all three forms of administration. The changes were Form 1-48% of baseline after 120 minutes; Form 2-47.9% of baseline after 60 minutes; Form 3-44.4% of baseline after 30 minutes. The greatest decrease was observed with form 1. The study indicates that significant bronchodilation was achieved in small children using the combination of fenoterol and ipratropium bromide administered by metered aerosol even when inhalation and the release of the puff were not synchronized. A significant bronchodilator effect was also observed in cases of severe bronchial obstruction in which transport of the active ingredients to the lower airways could not be sufficiently guaranteed.

Administration, Intranasal↗