INFORMATIVENESS OF IMPULSE OSCILLOMETRY IN THE DETECTION OF RESTRICTIVE TYPE VENTILATION DISORDERS

At present, there are a number of problems associated with the diagnosis of restrictive type of ventilation disorders: first, to identify restriction, it is necessary to perform body plethysmography, which is a laborious technique and requires the active cooperation of the patient with medical personnel; secondly, methodological issues that concern the criteria for the diagnosis of restriction are still under development. Impulse oscillometry (IOS) is a non-invasive and effortless technique for the patient to identify ventilation disorders, especially obstructive ones. In order to assess the informative value of IOS in the diagnosis of the restrictive ventilation disorders, respiratory impedance and its parameters were measured in 82 patients with various bronchopulmonary pathologies. The restriction was established on the basis of spirometric and bodyplethysmography studies. The results showed that IOS is a low-sensitivity method for detecting the restrictive type of ventilation disorders with mild reduced total lung capacity (TLC≥70%pred.), since in this case, the basic parameters of the IOS, such as the resistive component of the respiratory impedance (Rrs) at 5 and 20 Hz (Rrs5 and Rrs20, respectively), as well as the reactive component of the respiratory impedance at 5 Hz (Xrs5) remain within the normal values. When TLC was less than 70%pred., there was a decrease of Xrs5 with an increase in the resonance frequency and the preservation of the normal values of Rrs5 and Rrs20. The abnormal absolute frequency dependence of Rrs was determined at any degree of change in the TLC, increasing as it decreased.

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Impulse оscillometry in the diagnosis of moderate airway obstruction

Clinical Practice ◽

10.17816/clinpract9433-39 ◽

2018 ◽

Vol 9 (4) ◽

pp. 33-39

Author(s):

O. I. Savushkina ◽

A. V. Chernyak ◽

E. V. Kryukov ◽

A. A. Zaytsev ◽

Zh. K. Naumenko ◽

...

Keyword(s):

Airway Obstruction ◽

Airway Resistance ◽

Respiratory Mechanics ◽

Respiratory Impedance ◽

Impulse Oscillometry ◽

Non Invasive ◽

Invasive Method ◽

Group 2 ◽

Severe Airway Obstruction ◽

Group 1

Background: Impulse oscillometry (IOS) is a non-invasive method for determining respiratory impedance and its parameters. IOS has certain advantages over traditional spirometry. Aim: To assess the potential of IOS in the diagnosis of moderately severe airway obstruction. Methods: We examined 53 patients divided in two groups. The first group consisted of 29 patients (26 males and 3 females aged 42 to 89 years) with moderately severe obstructive abnormalities; the second group included 24 patients (17 males and 7 females aged from 18 to 68 years) without ventilatory defects. Results: Obstructive abnormalities were detected by IOS in 93% of patients in group 1, and the severity of obstruction was more pronounced compared to the results of spirometry in 37% of patients. In group 2, the IOS parameters were normal. There were significant differences in the lung function and IOS parameters between the first and second groups. There were significant correlations between airway resistance and IOS parameters in patients with moderately severe obstructive abnormalities. Conclusion: Thus impulse oscillometry can be used in the clinical practice to diagnose disorders of respiratory mechanics in patients with moderately severe airway obstruction.

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Validation of the Supine Venous Pump Function Test: A New Non-Invasive Tool in the Assessment of Deep Venous Insufficiency

Clinical Science ◽

10.1042/cs0910483 ◽

1996 ◽

Vol 91 (4) ◽

pp. 483-488 ◽

Cited By ~ 8

Author(s):

M. C. H. Janssen ◽

J. A. H. R. Claassen ◽

W. N. J. C. Van Asten ◽

H. Wollersheim ◽

M. J. M. De Rooij ◽

...

Keyword(s):

Venous Insufficiency ◽

Normal Values ◽

Venous Pressure ◽

Calf Muscle ◽

Pressure Measurements ◽

Limits Of Agreement ◽

Pump Function ◽

Non Invasive ◽

Calf Muscle Pump ◽

Function Test

1. A new non-invasive test was developed to assess calf muscle pump function: the supine venous pump function test. The technique uses strain-gauge plethysmography and is performed in the supine position. The method is superior to other non-invasive methods because basically the most essential haemodynamic parameter, venous pressure decrease, is used by properly converting venous volume measurements into venous pressure. The validity of this test was established by comparison with invasive venous pressure measurements and by determining the reproducibility. Additionally, normal values were determined. 2. In 28 extremities the supine venous pump function test was performed simultaneously with invasive venous pressure measurements. The reproducibility of the test was assessed in 10 randomly chosen volunteers. In 34 volunteers normal values were obtained and 26 patients with clinical venous insufficiency were examined. 3. Comparison of the two methods revealed a correlation coefficient of r = 0.98 (P < 0.001). A mean difference of 3.9%pf between both methods was found with limits of agreement of − 6.3%pf to 14.1%pf. The coefficient of repeatability was 13%pf and the coefficient of variation was 9%. The normal range was found to be >60%pf. The mean pump function in the patient group was 45%pf. 4. The limits of agreement are small enough to be confident that the supine venous pump function test can be used instead of invasive venous pressure measurements to assess calf muscle pump function in clinical practice. The reproducibility of the test is good.

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The pattern of urine cytology among patients with clinical diagnosis of bladder tumor in a tertiary hospital northwest Nigeria

International Surgery Journal ◽

10.18203/2349-2902.isj20194402 ◽

2019 ◽

Vol 6 (10) ◽

pp. 3521

Author(s):

Ahmed M. Umar ◽

Uzodimma E. Onwuasoanya ◽

Emmanuel U. Oyibo ◽

Adamu Dahiru ◽

Ismaila A. Mungadi

Keyword(s):

Bladder Cancer ◽

Clinical Diagnosis ◽

Bladder Tumour ◽

Tertiary Hospital ◽

Urine Cytology ◽

Female Ratio ◽

Non Invasive ◽

And Gender ◽

Low Sensitivity ◽

Age Range

Background: Urine cytology is a simple, safe, non-invasive and cheap investigation that is used as adjunct to cystoscopy in the diagnosis of bladder cancer. Its low sensitivity is a major limitation against its use as a sole diagnostic test for bladder cancer. The objective of this study was to determine the pattern of urine cytology seen in patients with clinical diagnosis of bladder tumour in our practice.Methods: This is a retrospective study of patients with clinical diagnosis of bladder tumour that had urine cytology in our centre. The age and gender of the patients, number of urine cytology per patient per year and cytologic diagnosis were analysed using the SPSS 20.Results: During the period under review, a total of 512 urine cytology was done for patients with clinical diagnosis of bladder tumour. The age range of the patients was 6 to 90 years with modal age of 60 years. 457 (89.3%) were males while 54 (10.5%) were females and 1 (0.2%) was unspecified. Male to female ratio was 8.5:1. The highest number of urine cytology was done in 2013 with 64 (12.5%) while the least number was 1 (0.2%) recorded in 2001 and 2003. Only 68 (13.3%) specimens were reported to be malignant while 245 (47.9%) were reported as negative representing the most common cytological diagnosis in the study.Conclusions: Although urine cytology is useful in the diagnostic workup of patients with bladder mass, it is unlikely it would supplant cystoscopy and biopsy in the diagnosis of bladder cancer.

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Recent 31 P n.m.r. studies of myocardium

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1980.0060 ◽

1980 ◽

Vol 289 (1037) ◽

pp. 437-439 ◽

Cited By ~ 5

Keyword(s):

Mechanical Performance ◽

Normal Values ◽

Chemical Exchange ◽

Exchange Reactions ◽

Perfused Heart ◽

Time Intervals ◽

Non Invasive ◽

Biochemical State ◽

Perfused Hearts ◽

Kinetics Of

Earlier work from this laboratory has concerned the possible use of phosphorus n.m.r. as a method to monitor, in a non-invasive manner, the biochemical state of the perfused heart as a function of its mechanical performance. We showed that a simulated coronary infarction could be detected by 31 P n.m.r. (Hollis et al 1978 a and that hypothermia and KC1 arrest could preserve the pH and the ATP levels at more nearly normal values than in a non-arrested heart during long periods (40 min) of ischaemia (Hollis et al . 1978 b ).More recently it was shown that multiple doses of KC1, given at intervals, were more effective in this respect than was a single dose (Flaherty et al . 1979). These studies essentially followed the kinetics of transitions of the heart between two or more distinct physiological states (i.e. normoxic and ischaemic, with or without KC1 arrest) by observation of the 31 P n.m.r. spectra at various time intervals over periods of up to 1 h. As described in detail and demonstrated in Dr Truman Brown’s contribution to these discussions, the rates of chemical exchange reactions occurring in a steady state can be measured by the techniques of saturation transfer in various biological systems, including perfused hearts.

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Abstract WP432: Non-invasive Respiratory Impedance Enhances Cerebral Perfusion

Stroke ◽

10.1161/str.48.suppl_1.wp432 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Christopher G Favilla ◽

Ashwin B Parthasarathy ◽

John A Detre ◽

Michael T Mullen ◽

Scott E Kasner ◽

...

Keyword(s):

Blood Flow ◽

Cardiac Output ◽

Flow Velocity ◽

Cerebral Perfusion ◽

Respiratory Impedance ◽

Mean Flow ◽

Non Invasive ◽

End Tidal ◽

High Level ◽

Mean Flow Velocity

Background: Optimization of cerebral blood flow is the cornerstone of clinical management in a number of neurologic diseases, most notably ischemic stroke. Intra-thoracic pressure influences cardiac output and has the potential to impact cerebral blood flow (CBF). Here we aim to quantify cerebral hemodynamic changes in response to increased respiratory impedance using a non-invasive respiratory device. Methods: Cerebral perfusion was measured under varying levels of respiratory impedance (6cm H 2 0, 9cm H 2 0, and 12 cm H 2 0) in 20 healthy volunteers. Simultaneous measurements of microvascular CBF and middle cerebral artery mean flow velocity (MFV), respectively, were performed with optical diffuse correlation spectroscopy (DCS) and transcranial Doppler ultrasound (TCD). Results: At the high level of respiratory impedance, mean flow velocity increased by 6.4% compared to baseline (p=0.004), but changes in cortical CBF were smaller and non-significant (Figure). Heart rate, cardiac output, respiratory rate, and end tidal CO 2 remained stable during all levels of respiratory impedance. There was small increase in mean arterial blood pressure, 1.7% (p=0.006), at the high level of respiratory impedance. In a multivariable linear regression model accounting for end tidal CO 2 and individual variability, respiratory impedance was associated with increases in both mean flow velocity (coefficient: 0.49, p<0.001) and cortical CBF (coefficient: 0.13, p<0.001). Conclusions: Manipulating intrathoracic pressure via non-invasive respiratory impedance was well tolerated and produced a small but measurable increase in cerebral perfusion in healthy individuals. Future studies in acute ischemic stroke patients with impaired cerebral autoregulation is warranted in order to assess whether respiratory impedance is feasible as a novel non-invasive therapy for stroke.

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Abstract 15974: Non-Invasive Myocardial Work Indices in Normal Adolescents: A Pilot Study

Circulation ◽

10.1161/circ.142.suppl_3.15974 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Sarah Pradhan ◽

Anna Mullikin ◽

Vien T Truong ◽

Wojciech Mazur ◽

Michael D Taylor ◽

...

Keyword(s):

Blood Pressure ◽

Pilot Study ◽

Normal Values ◽

Global Longitudinal Strain ◽

Lv Function ◽

Healthy Adolescent ◽

Non Invasive ◽

Work Index ◽

The Mean ◽

Global Work

Introduction: Myocardial work may provide a different perspective on LV function and energy consumption. Its non-invasive assessment by echocardiography correlates with invasive measures and there are normal values established in adult patients. We aimed to establish normal values in a healthy adolescent population. Methods: Nineteen healthy subjects (mean age = 15 ± 2 years, 42% male) with normal echocardiograms were prospectively included. Brachial cuff blood pressure was obtained immediately following apical images in the supine position. Post-processing of echocardiograms with speckle tracking echocardiography and derivation of global myocardial work indices from LV pressure-strain loops was done using EchoPAC (General Electric, v203R73.0) (Figure 1). Results: Baseline demographics, echocardiographic measures and global myocardial work indices are reported in Table 1. The mean global work index is 1833 ± 278 mmHg with mean global work efficiency of 95 ± 1.3%. No gender difference in myocardial work indices are found (p>0.05 for all). Correlation between global work indices with age, systolic blood pressure, LV ejection fraction, and global longitudinal strain (GLS) are presented in Table 2. Conclusions: This is a pilot study to begin establishing normal adolescent indices of non-invasive myocardial work. Figure 1. Example

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Abstract TMP87: Non-Invasive Respiratory Impedance Enhances Cerebral Perfusion in Acute Stroke Patients

Stroke ◽

10.1161/str.49.suppl_1.tmp87 ◽

2018 ◽

Vol 49 (Suppl_1) ◽

Author(s):

Christopher G Favilla ◽

Rodrigo M Forti ◽

Ahmad Zamzam ◽

John A Detre ◽

Michael T Mullen ◽

...

Keyword(s):

Acute Stroke ◽

Cerebral Perfusion ◽

Respiratory Impedance ◽

Stroke Patients ◽

Non Invasive

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Assessment of markers of bone formation under controlled environmental factors and their correlation with serum minerals in adult sheep as a model for orthopaedic research

Laboratory Animals ◽

10.1258/la.2007.06037e ◽

2008 ◽

Vol 42 (4) ◽

pp. 465-472 ◽

Cited By ~ 10

Author(s):

I R Dias ◽

C A Viegas ◽

J T De Azevedo ◽

E M Costa ◽

P Lourenço ◽

...

Keyword(s):

Normal Values ◽

Healing Process ◽

Average Weight ◽

Serum Electrolyte ◽

Blood Samples ◽

Non Invasive ◽

Serum Minerals ◽

The Mean ◽

Bone Healing Process ◽

Markers Of Bone Formation

Summary Eighteen healthy skeletally mature (3 years old) ewes, with an average weight of 45 kg, of the Portuguese Churra da Terra Quente breed were used to evaluate the normal values of total and bone-specific isoform of alkaline phosphatase serum activities (ALP and BALP, respectively) and serum osteocalcin (OC) and their correlation with the serum minerals - calcium (Ca), phosphorus (P), magnesium (Mg) and ionized calcium (Ca2+). The sheep were maintained under controlled environmental conditions (constant diurnal photoperiod cycle and identical husbandry and feeding) for six weeks before the collection of the blood samples. The measurement of the total ALP and serum minerals was performed with automated biochemistry analysers using the BioMérieux® kits, the serum electrolyte Ca2+ Diametrics Medical, Inc® specific cassettes and the BALP and OC METRATM kits from QUIDEL® Corporation. The mean ± standard deviation values obtained were: total ALP 90.17 ± 85.72 U/L, BALP 15.0 ± 5.44 U/L, ratio BALP/ total ALP 29.28 ± 24.22, OC 13.02 ± 1.87 ng/mL, Ca 2.57 ± 0.37 mmol/L, P 2.13 ± 0.42 mmol/L, Mg 1.04 ± 0.13 mmol/L, Ca2+ 1.29 ± 0.04 mmol/L. Significant correlations were observed between the total ALP and Ca ( r = 0.5939; P = 0.05) and OC and Ca ( r = 0.5706; P = 0.05). Reference to the serum values of bone turnover parameters in sheep could be of great value in research and could provide complementary non-invasive information on the bone healing process, particularly with regard to obtaining an early prognosis of fracture healing.

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The Diagnosis of Established Deep Vein Thrombosis

10.1055/s-0039-1687465 ◽

1979 ◽

Author(s):

R. Hull ◽

J. Hirsh

Keyword(s):

Deep Vein Thrombosis ◽

Doppler Ultrasonography ◽

Clinical Symptoms ◽

Reference Method ◽

Impedance Plethysmography ◽

Vein Thrombosis ◽

Non Invasive ◽

Patient Morbidity ◽

Low Sensitivity ◽

Deep Vein

It is now generally accepted that the clinical diagnosis of deep venous thrombosis (DVT) is inaccurate both because of low sensitivity and specificity. Because more than 50% of symptomatic patients fail to show thrombi on venography, anticoagulant therapy on the basis of clinical symptoms of DVT is not acceptable. Venography has been the standard reference method for the diagnosis of DVT but is invasive and consequently associated with patient morbidity. Impedance plethysmography (IPG) and Doppler ultrasonography (Doppler) are both non-invasive and, in patients with clinically suspected DVT, are sensitive and specific tests for proximal DVT. Both tests are relatively insensitive to calf DVT. IPG has the advantage of being an objective technique whereas Doppler is subjective and its accuracy may suffer in inexperienced hands. 125I fibrinogen leg scanning (leg scanning) is an inappropriate test when used alone in patients with clinically suspected DVT as it is insensitive in the upper thigh, may be negative in 30% of patients with established DVT and may take up to 72 hours to become positive. The combination, however, of IPG and leg scanning provides an accurate approach for the detection of both proximal and calf DVT in patients with established DVT. This approach is not associated with patient morbidity and offers the clinician an alternative to venography.

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