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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

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↗

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↗

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↗

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

Atrial natriuretic peptide decreases hepatic and cardiac blood content, but increases intestinal blood content in supine humans.

The authors evaluated in humans whether atrial natriuretic peptide (ANP) alters the regional distribution of blood in capacitance vessels. Eight healthy male volunteers (mean age: 30 years, range: 24-39) were studied twice. On different days and in a randomized, double blind fashion they received either alpha h-ANP (99-126), 25 micrograms intravenously followed by infusion of 0.1 microgram kg-1 min-1, or vehicle. Changes of regional blood content in heart, liver, and intestine were evaluated at 3-min intervals using autologous radioactively (99mTc) labeled red cells. Calf circumference (strain gauge), central venous pressure, and heart rate were recorded continuously while arterial pressure (oscillometry), hematocrit, ANP and cGMP plasma concentrations were determined intermittently. Exogenous ANP increased plasma concentrations of ANP (49 pg ml-1 +/- 8 SE to 614 +/- 190) and cGMP (1.7 pmol ml-1 +/- 0.2 to 30.8 +/- 4.4). This elicited significant and profound decreases in liver (-11%) and cardiac (-10%) radioactivity, contrasted by a smaller but significant increase (+4%) of intestinal radioactivity. These changes became gradually apparent about 15 min during ANP administration and reached their nadir at the end of the infusion period. Central venous pressure significantly decreased by 3.4 cm H2O and calf volume by 0.3 ml/100 ml while hematocrit increased by 2.6%. All changes were at least partly reversed when ANP administration ceased. Of note, two subjects developed a near syncope with abrupt bradycardia and arterial hypotension following an initial gradual decrease in cardiac counts and central venous pressure. We conclude that in humans ANP markedly alters the regional blood distribution in the capacitance vasculature as blood content decreased profoundly in both heart and liver, but increased in the intestine, albeit to a lesser extent. Accordingly, a redistribution of blood away from the heart represents another unique mechanism by which ANP can exert its cardiovascular actions.

Adult↗

PubMed1991

[Controlled trial of a non-invasive continuous blood pressure monitor: Cortronic AMP 770].

The performances of a Cortronic AMP 770 monitor, a new apparatus for non invasive continuous blood pressure monitoring was assessed. Its working principle is derived from oscillometry. The blood pressure cuff is kept at a low pressure (about 20 mmHg), and the oscillations induced by the arterial pulse are converted into blood pressure. Systolic, mean and diastolic blood pressure was measured in 9 healthy volunteers, under physiological conditions, using both the AMP 770 and a traditional oscillometer (Physiogard SM 785 NI, Odam). A group of 124 paired measurements was obtained, with values ranging from 87 to 150 mmHg for systolic pressure, from 48 to 97 mmHg for diastolic pressure, and from 63 to 114 mmHg for mean pressure. The mean differences (APM 770-Physiogard) were -1.2 +/- 10 mmHg for systolic pressure, 3.2 +/- 8 mmHg for diastolic pressure, and -3.8 +/- 8 mmHg for mean pressure. There was no correlation between blood pressure levels and discrepancy in the measurements obtained with the two methods. The Cortronic AMP 770 was reliable under normal circumstances, when compared with a traditional oscillometer. However further studies are required to assess its reliability under pathological circumstances (severe hypotension or hypertension, arrhythmias and sudden changes in blood pressure).

Adult↗

PubMed1976

Peripheral circulation, particularly heat regulation reactions, in patients with amyloidosis and polyneuropathy.

As patients with amyloidosis and polyneuropathy often have signs and symptoms of circulatory disturbances in the extremities, especially the legs, we have examined such patients and controls with oscillometry and digital pulse plethysmography in order to estimate the occurrence of any arterial circulatory insufficiency. No signs of significant obliterative arterial changes were found. Skin temperature was also determined in fingers and toes during body-cooling and at subsequent indirect heating. At low environmental temperature the skin temperature was higher in patients than in controls. In a few patients there was almost no decrease in skin temperature, despite a long period of cooling and a low rectal temperature. Indirect heating elicited a marked increase in the skin temperature of the toes and fingers of the controls. In most patients this reaction was completely absent in the toes and absent or reduced in the fingers. These deviations can be explained by nerve damage caused by amyloid deposition in the nerves. Amyloid deposits in the wall of small blood vessels may be an additional factor. Maximum blood flow in the anterior tibial muscle after combined ischemia and exercise, investigated with radioactive xenon, was reduced in half of the patients.

Adult↗

PubMed1992

Thoracic electrical bioimpedance measurement of cardiac output and cardiovascular responses to the induction of anaesthesia and to laryngoscopy and intubation.

Noninvasive methods of determining cardiac output (by thoracic electrical bioimpedance) and arterial pressure (by intermittent oscillometry) were used to record minute-by-minute changes in heart rate, mean arterial pressure, stroke volume, cardiac output and systemic vascular resistance following induction of general anaesthesia and laryngoscopy and intubation in 60 healthy female patients who were either unpremedicated, or premedicated with temazepam or papaveretum-hyoscine. Anaesthesia was induced with a sleep dose (3-5 mg.kg-1) of thiopentone and maintained with 70% nitrous oxide in oxygen with 0.5-1% enflurane. Tracheal intubation was facilitated by administration of vecuronium 0.1 mg.kg-1. Mean arterial pressure and cardiac output decreased maximally 5 min after induction in all premedication groups by mean estimates of 21-25% and 14-22% respectively. Heart rate increased initially one minute after induction, but decreased to less than the baseline value 5 min after induction. Systemic vascular resistance was unchanged. The stimulus of laryngoscopy and tracheal intubation was accompanied by a significant pressor response and tachycardia one minute after intubation (with mean increases in mean arterial pressure and heart rate of 29-34% and 22-33% respectively). The increase in mean arterial pressure was secondary to an increase in systemic vascular resistance (36-57%), and was accompanied by a decrease in stroke volume (-25 to -31%). These changes were significant in all three groups. Cardiac output decreased only in unpremedicated patients. There were wide variations in the different haemodynamic indices.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1977

Late voice function after surgical injury to the recurrent nerve.

In the period 1960 to 1970, a total of 213 patients underwent subtotal thyroidectomy for benign cervical toxic goitre. Postoperatively, immobile vocal cord indicating paralysis of the recurrent nerve was found in 17 patients. In 8 patients, immobility of the vocal cord was permanent. Seven of the 17 patients received voice training which was initiated within 3 weeks after operation. After a period of 5-10 years, on an average 8 years, the 17 patients had a clinical and a comprehensive objective examination of the voice function comprising stroboscopy, electroglottography, phono-oscillometry, voice range, phonation time, peak-flow and pitch. Only a few complaints were ciliated whereas the objective examination of the voice function revealed abnormal findings in all but one patient. The findings were less abnormal in patients who had received early voice training. It is concluded that despite abnormal objective findings, all 17 patients found their voice function satisfactory. Moreover, early voice training seemed to offer a fair chance of minimizing late voice problems, whether the paralysis was permanent or transitory.

Adult↗

PubMed1992

Correlation between computer-assisted femoral arteriography and physiological tests in hypercholesterolaemic patients: a methodological study with special reference to clinical trials.

The validity of computer-assisted femoral arteriography, for the study of regression/progression of atherosclerosis in follow-up clinical trials, was investigated by comparison with routine physiological estimates of peripheral circulatory function. Thus, in 114 hypercholesterolaemic patients, the results of aorto-femoral arteriography were compared with those of leg segmental blood pressure measurement, oscillometry, digital pulse plethysmography, and bicycle and treadmill exercise tests. In 107 patients, 18 with symptoms of peripheral vascular disease (PVD) and 89 asymptomatic, magnification arteriograms of a 20 cm segment of the right or left superficial femoral artery were obtained. These arteriograms were digitized and the following variables were calculated: arterial lumen volume (corrected for body size), per cent stenosis, and edge roughness. The correlation between arteriographic and physiological variables was investigated with a linear regression model, taking into account the possible interaction with sex, and presence or absence of symptoms of PVD. Lumen volume correlated significantly with all five physiological variables, and per cent stenosis correlated significantly with four of the physiological variables. For the roughness measure, however a significant correlation was found only with plethysmography. By using logistic multiple regression analysis linear functions of physiological variables were constructed to detect ilio-femoral arterial occlusion. The sensitivity/specificity for detection of right-sided, left-sided, and bilateral occlusion was 0.83/0.98, 0.78/0.98, and 0.60/1.00 respectively (N = 108-111). Systolic blood pressure (ankle-arm ratio) was the single variable most closely correlated to the likelihood of arterial occlusions. It is concluded that arterial lumen volume and per cent stenosis, measured for the digitized femoral arteriogram, correlate well with physiological variables, which reflect the state of atherosclerosis both in the femoral arteries and in other arterial beds including the heart, and that routine physiological tests can be used to identify patients with arterial occlusions in the iliac and femoral arteries.

Adult↗

PubMed2024

Design of the SPIROMICS Study of Early COPD Progression: SOURCE Study.

BACKGROUND: The biological mechanisms leading some tobacco-exposed individuals to develop early-stage chronic obstructive pulmonary disease (COPD) are poorly understood. This knowledge gap hampers development of disease-modifying agents for this prevalent condition. OBJECTIVES: Accordingly, with National Heart, Lung and Blood Institute support, we initiated the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS) Study of Early COPD Progression (SOURCE), a multicenter observational cohort study of younger individuals with a history of cigarette smoking and thus at-risk for, or with, early-stage COPD. Our overall objectives are to identify those who will develop COPD earlier in life, characterize them thoroughly, and by contrasting them to those not developing COPD, define mechanisms of disease progression. METHODS/DISCUSSION: SOURCE utilizes the established SPIROMICS clinical network. Its goal is to enroll n=649 participants, ages 30-55 years, all races/ethnicities, with ≥10 pack-years cigarette smoking, in either Global initiative for chronic Obstructive Lung Disease (GOLD) groups 0-2 or with preserved ratio-impaired spirometry; and an additional n=40 never-smoker controls. Participants undergo baseline and 3-year follow-up visits, each including high-resolution computed tomography, respiratory oscillometry and spirometry (pre- and postbronchodilator administration), exhaled breath condensate (baseline only), and extensive biospecimen collection, including sputum induction. Symptoms, interim health care utilization, and exacerbations are captured every 6 months via follow-up phone calls. An embedded bronchoscopy substudy involving n=100 participants (including all never-smokers) will allow collection of lower airway samples for genetic, epigenetic, genomic, immunological, microbiome, mucin analyses, and basal cell culture. CONCLUSION: SOURCE should provide novel insights into the natural history of lung disease in younger individuals with a smoking history, and its biological basis.

SPIROMICS↗

PubMed1975

Xylose absorption test before and after surgical repair of coarctation of the aorta.

The aim of the study was to ascertain whether the acceleration of physical development in children after operation for coarctation of the aorta is due to the improved intestinal absorption. Lowered values of the oral xylose absorption test were found in all 9 patients before surgery. In all the patients who had been operated on, sphigmo-oscillometry revealed an increased pulsatile character of the blood flow, pulsatile volume in the lower extremities, and a rise of mean arterial blood pressure in this area. On the other hand, surgical repair had no influence on the renal blood flow as evidenced by PAH clearance and isotope renography. There was no correlation of diuresis and the xylose excretion test. Increased values of the xylose test after operation for coarctation of the aorta are due to the increased intestinal absorption rather than to improved renal function. Improved intestinal absorption may be a factor responsible for the accelerated physical development of children operated on for coarctation of the aorta.

Adolescent↗