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Veterinary Journal (London, England :... Jun 2024Arterial blood pressure (ABP) is often measured with oscillometry during anaesthesia. Changing the height of the measuring cuff with respect to the level of the heart is...
Arterial blood pressure (ABP) is often measured with oscillometry during anaesthesia. Changing the height of the measuring cuff with respect to the level of the heart is known to affect oscillometry accuracy in some species; however, this effect has not been investigated in cats. The objective of this study was to determine the effects of raising and lowering the measuring cuff from standard position (level of the heart) on ABP, measured with PetMAP, in anaesthetised cats. ABP readings were obtained from 29 cats with the cuff at standard position (baseline), and 5 cm above and below the heart. The end-tidal isoflurane concentrations were maintained constant during data acquisition. There were no differences between baseline values and those measured below the heart, while ABP measured above the heart was consistently lower than baseline for both the thoracic and pelvic limbs (P < 0.001), with absolute differences of 8.2 (2.5 - 14) mmHg and 6.5 (3.0 - 15.0) mmHg, respectively. Systolic ABP readings at the pelvic limb were consistently higher than those at the thoracic limb at standard position (112 ± 26 versus 103 ± 21 mmHg, p = 0.010), above (106 ± 22 versus 95 ± 20 mmHg, p = 0.003), and below the heart (116 ± 26 versus 107 ± 22 mmHg, p = 0.011). This study shows that raising the cuff by 5 cm above the heart, which may become necessary during procedural positioning, results in clinically significant underestimation of ABP measured with PetMAP.
Topics: Animals; Cats; Blood Pressure Determination; Oscillometry; Male; Female; Arterial Pressure; Anesthesia; Extremities; Blood Pressure
PubMed: 38759724
DOI: 10.1016/j.tvjl.2024.106137 -
Respiratory Research May 2024Limited research has investigated the relationship between small airway dysfunction (SAD) and static lung hyperinflation (SLH) in patients with post-acute sequelae of... (Observational Study)
Observational Study
BACKGROUND
Limited research has investigated the relationship between small airway dysfunction (SAD) and static lung hyperinflation (SLH) in patients with post-acute sequelae of COVID-19 (PASC) especially dyspnea and fatigue.
METHODS
64 patients with PASC were enrolled between July 2020 and December 2022 in a prospective observational cohort. Pulmonary function tests, impulse oscillometry (IOS), and symptom questionnaires were performed two, five and eight months after acute infection. Multivariable logistic regression models were used to test the association between SLH and patient-reported outcomes.
RESULTS
SLH prevalence was 53.1% (34/64), irrespective of COVID-19 severity. IOS parameters and circulating CD4/CD8 T-cell ratio were significantly correlated with residual volume to total lung capacity ratio (RV/TLC). Serum CD8 + T cell count was negatively correlated with forced expiratory volume in the first second (FEV) and forced vital capacity (FVC) with statistical significance. Of the patients who had SLH at baseline, 57% continued to have persistent SLH after eight months of recovery, with these patients tending to be older and having dyspnea and fatigue. Post-COVID dyspnea was significantly associated with SLH and IOS parameters R5-R20, and AX with adjusted odds ratios 12.4, 12.8 and 7.6 respectively. SLH was also significantly associated with fatigue.
CONCLUSION
SAD and a decreased serum CD4/CD8 ratio were associated with SLH in patients with PASC. SLH may persist after recovery from infection in a substantial proportion of patients. SAD and dysregulated T-cell immune response correlated with SLH may contribute to the development of dyspnea and fatigue in patients with PASC.
Topics: Humans; Male; Female; Middle Aged; COVID-19; Prospective Studies; Post-Acute COVID-19 Syndrome; Lung; Respiratory Function Tests; Aged; Adult; Recovery of Function; Time Factors; Dyspnea; Forced Expiratory Volume
PubMed: 38750527
DOI: 10.1186/s12931-024-02830-1 -
PloS One 2024In cardiology, cardiac output (CO) is an important parameter for assessing cardiac function. While invasive thermodilution procedures are the gold standard for CO... (Comparative Study)
Comparative Study
BACKGROUND
In cardiology, cardiac output (CO) is an important parameter for assessing cardiac function. While invasive thermodilution procedures are the gold standard for CO assessment, transthoracic Doppler echocardiography (TTE) has become the established method for routine CO assessment in daily clinical practice. However, a demand persists for non-invasive approaches, including oscillometric pulse wave analysis (PWA), to enhance the accuracy of CO estimation, reduce complications associated with invasive procedures, and facilitate its application in non-intensive care settings. Here, we aimed to compare the TTE and oscillometric PWA algorithm Antares for a non-invasive estimation of CO.
METHODS
Non-invasive CO data obtained by two-dimensional TTE were compared with those from an oscillometric blood pressure device (custo med GmbH, Ottobrunn, Germany) using the integrated algorithm Antares (Redwave Medical GmbH, Jena, Germany). In total, 59 patients undergoing elective cardiac catheterization for clinical reasons (71±10 years old, 76% males) were included. Agreement between both CO measures were assessed by Bland-Altman analysis, Student's t-test, and Pearson correlations.
RESULTS
The mean difference in CO was 0.04 ± 1.03 l/min (95% confidence interval for the mean difference: -0.23 to 0.30 l/min) for the overall group, with lower and upper limits of agreement at -1.98 and 2.05 l/min, respectively. There was no statistically significant difference in means between both CO measures (P = 0.785). Statistically significant correlations between TTE and Antares CO were observed in the entire cohort (r = 0.705, P<0.001) as well as in female (r = 0.802, P<0.001) and male patients (r = 0.669, P<0.001).
CONCLUSIONS
The oscillometric PWA algorithm Antares and established TTE for a non-invasive estimation of CO are highly correlated in male and female patients, with no statistically significant difference between both approaches. Future validation studies of the Antares CO are necessary before a clinical application can be considered.
Topics: Humans; Male; Female; Cardiac Output; Algorithms; Aged; Pulse Wave Analysis; Echocardiography, Doppler; Middle Aged; Aged, 80 and over; Oscillometry
PubMed: 38739601
DOI: 10.1371/journal.pone.0302793 -
Journal of Asthma and Allergy 2024Prediction of asthma in preschool children is challenging and lacks objective indicators. The aim is to observe and analyze the variances between impulse oscillometry...
OBJECTIVE
Prediction of asthma in preschool children is challenging and lacks objective indicators. The aim is to observe and analyze the variances between impulse oscillometry (IOS) and fractional expiratory nitric oxide (FeNO) in preschool children with wheezing, establish a joint prediction model, and explore the diagnostic value of combining IOS with FeNO in diagnosing asthma among preschool children.
PATIENTS AND METHODS
This study enrolled children aged 3-6 years with wheezing between June 2021 and June 2022. They were categorized as asthmatic (n=104) or non-asthmatic (n=109) after a 1-year follow-up. Clinical data, along with IOS and FeNO measurements from both groups, underwent univariate regression and multiple regression analyses to identify predictive factors and develop the most accurate model. The prediction model was built using the stepwise (stepAIC) method. The receiver operating characteristic curve (ROC), calibration curve, Hosmer-Lemeshow test, and decision curve analysis (DCA) were employed to validate and assess the model.
RESULTS
During univariate analysis, a history of allergic rhinitis, a history of eczema or atopic dermatitis, and measures including FeNO, R5, X5, R20, Fres, and R5-R20 were found to be associated with asthma diagnosis. Subsequent multivariate analysis revealed elevated FeNO, R5, and X5 as independent risk factors. The stepAIC method selected five factors (history of allergic rhinitis, history of eczema or atopic dermatitis, FeNO, R5, X5) and established a prediction model. The combined model achieved an AUROC of 0.94, with a sensitivity of 0.89 and specificity of 0.88, surpassing that of individual factors. Calibration plots and the HL test confirmed satisfactory accuracy.
CONCLUSION
This study has developed a prediction model based on five factors, potentially aiding clinicians in early identification of asthma risk among preschool children.
PubMed: 38736906
DOI: 10.2147/JAA.S460193 -
BMC Pediatrics May 2024Cough variant asthma (CVA) is one of the most common causes of chronic cough in children worldwide. The diagnosis of CVA in children remains challenging. This study...
BACKGROUND
Cough variant asthma (CVA) is one of the most common causes of chronic cough in children worldwide. The diagnosis of CVA in children remains challenging. This study aimed to assess the diagnostic utility of impulse oscillometry (IOS) pulmonary function in children with CVA.
METHODS
This study included children aged 4 to 12 years diagnosed with CVA who underwent IOS pulmonary function and bronchodilation (BD) tests. A control group of healthy children was matched. Pre- and post-BD IOS parameters were recorded and presented as mean ± standard deviation or median. Receiver operating characteristic (ROC) curves were plotted, and the area under the curve (AUC) was calculated to evaluate the discriminatory potential of the IOS parameters for diagnosing CVA.
RESULTS
A total of 180 patients with CVA and 65 control subjects were included. The baseline IOS parameters in the CVA group, except X5%pred, were significantly greater compared to the control group. After inhalation of salbutamol sulfate, all IOS parameters improved significantly in the CVA group. However, Z5%pred, R5%pred, and R20%pred remained greater in the CVA group compared to the control group. The improvement rates of IOS parameters in the CVA group significantly surpassed those in the control group. The ROC curve results for pre-BD IOS parameters and the improvement rate during the BD test showed that the combinations of pre-Z5%pred+Z5% and pre-R5%pred+R5% achieved the highest AUC value of 0.920 and 0.898, respectively. The AUC values of these combined parameters surpassed those of individual ones.
CONCLUSIONS
This study highlights that children with CVA exhibit greater IOS parameters compared to healthy children. The changes in IOS parameters during the BD test provided valuable diagnostic information for CVA, and the combination of various parameters can help pediatricians accurately identify CVA in children.
Topics: Humans; Cough; Child; Asthma; Male; Female; Oscillometry; Child, Preschool; Case-Control Studies; ROC Curve; Albuterol; Respiratory Function Tests; Bronchodilator Agents; Cough-Variant Asthma
PubMed: 38702638
DOI: 10.1186/s12887-024-04749-4 -
Journal of the Formosan Medical... Apr 2024
Comment on "Correlation between impulse oscillometry parameters and test for respiratory and asthma control in kids (TRACK) in asthma control of preschoolers with asthma": Subtitle: impulse oscillometry parameters and asthma.
PubMed: 38692972
DOI: 10.1016/j.jfma.2024.04.015 -
Journal of Clinical Medicine Apr 2024Several studies have demonstrated the positive clinical and functional impact of adding Long-Acting Muscarinic Antagonist (LAMA) to Inhaled Corticosteroids (ICS) and...
Several studies have demonstrated the positive clinical and functional impact of adding Long-Acting Muscarinic Antagonist (LAMA) to Inhaled Corticosteroids (ICS) and Long-Acting Beta-Agonists (LABA) therapy in the treatment of severe asthma. Aim and objectives: To demonstrate that treating Small Airways Disease (SAD) in severe asthma patients who are candidates for biologics can improve respiratory symptoms, lung function, and airways inflammation, potentially avoiding or delaying the use of biological therapy. Thirty-two severe asthma patients with SAD were transitioned from separate inhalers for ICS/LABA and LAMA to extrafine single-inhaler beclomethasone, formoterol, and glycopyrronium. None of these patients underwent biological therapy before the study. Follow-up evaluations were conducted at baseline (T0) and three months after initiation (T3). Assessments included clinical evaluations, spirometry, oscillometry, and inflammation markers. Transitioning to single-inhaler triple therapy from T0 to T3 resulted in significant improvements in Asthma Control Test (ACT) and SAD parameters, including increased Forced Expiratory Volume in the mid-range of lung capacity and improved airway resistance and reactance measurements using impulse oscillometry. A significant reduction in airway inflammation was evidenced by lower levels of Fractional Exhaled Nitric Oxide 350 (FeNO 350) ( < 0.001 for all). : Adopting a single-inhaler triple therapy notably enhanced clinical control and small airway function in patients with severe asthma and SAD, supporting the positive impact of target-therapy for the achievement of a stable state termed "Quiet Asthma".
PubMed: 38673593
DOI: 10.3390/jcm13082320 -
Journal of Personalized Medicine Apr 2024We aimed to develop and validate a machine learning model using impulse oscillometry system (IOS) profiles for accurately classifying patients into three...
We aimed to develop and validate a machine learning model using impulse oscillometry system (IOS) profiles for accurately classifying patients into three assessment-based categories: no airflow obstruction, asthma, and chronic obstructive pulmonary disease (COPD). Our research questions were as follows: (1) Can machine learning methods accurately classify obstructive disease states based solely on multidimensional IOS data? (2) Which IOS parameters and modeling algorithms provide the best discrimination? We used data for 480 patients (240 with COPD and 240 with asthma) and 84 healthy individuals for training. Physiological and IOS parameters were combined into six feature combinations. The classification algorithms tested were logistic regression, random forest, neural network, k-nearest neighbor, and support vector machine. The optimal feature combination for identifying individuals without pulmonary obstruction, with asthma, or with COPD included 15 IOS and physiological features. The neural network classifier achieved the highest accuracy (0.786). For discriminating between healthy and unhealthy individuals, two combinations of twenty-three features performed best in the neural network algorithm (accuracy of 0.929). When distinguishing COPD from asthma, the best combination included 15 features and the neural network algorithm achieved an accuracy of 0.854. This study provides compelling technical evidence and clinical justifications for advancing IOS data-driven models to aid in COPD and asthma management.
PubMed: 38673025
DOI: 10.3390/jpm14040398 -
Frontiers in Medicine 2024Prior studies assessing outcomes of lung transplants from cigarette-smoking donors found mixed results. Oscillometry, a non-invasive test of respiratory impedance,...
INTRODUCTION
Prior studies assessing outcomes of lung transplants from cigarette-smoking donors found mixed results. Oscillometry, a non-invasive test of respiratory impedance, detects changes in lung function of smokers prior to diagnosis of COPD, and identifies spirometrically silent episodes of rejection post-transplant. We hypothesise that oscillometry could identify abnormalities in recipients of smoking donor lungs and discriminate from non-smoking donors.
METHODS
This prospective single-center cohort study analysed 233 double-lung recipients. Oscillometry was performed alongside routine conventional pulmonary function tests (PFT) post-transplant. Multivariable regression models were constructed to compare oscillometry and conventional PFT parameters between recipients of lungs from smoking vs non-smoking donors.
RESULTS
The analysis included 109 patients who received lungs from non-smokers and 124 from smokers. Multivariable analysis identified significant differences between recipients of smoking and non-smoking lungs in the oscillometric measurements R, X, AX, Rz and Xz, but no differences in %predicted FEV, FEV/FVC, %predicted TLC or %predicted DLCO. An analysis of the smoking group also demonstrated associations between increasing smoke exposure, quantified in pack years, and all the oscillometry parameters, but not the conventional PFT parameters.
CONCLUSION
An interaction was identified between donor-recipient sex match and the effect of smoking. The association between donor smoking and oscillometry outcomes was significant predominantly in the female donor/female recipient group.
PubMed: 38654829
DOI: 10.3389/fmed.2024.1328395 -
BMC Pulmonary Medicine Apr 2024Fractional exhaled nitric oxide (FeNO) has been extensively studied in various causes of pulmonary hypertension (PH), but its utility as a noninvasive marker remains...
BACKGROUND
Fractional exhaled nitric oxide (FeNO) has been extensively studied in various causes of pulmonary hypertension (PH), but its utility as a noninvasive marker remains highly debated. The objective of our study was to assess FeNO levels in patients with idiopathic pulmonary arterial hypertension (IPAH) and mixed connective tissue disease complicating pulmonary hypertension (MCTD-PH), and to correlate them with respiratory functional data, disease severity, and cardiopulmonary function.
METHODS
We collected data from 54 patients diagnosed with IPAH and 78 patients diagnosed with MCTD-PH at the Shanghai Pulmonary Hospital Affiliated to Tongji University. Our data collection included measurements of brain natriuretic peptide (pro-BNP), cardiopulmonary exercise test (CPET), pulmonary function test (PFT), impulse oscillometry (IOS), and FeNO levels. Additionally, we assessed World Health Organization functional class (WHO-FC) of each patient.
RESULTS
(1) The fractional exhaled concentration of nitric oxide was notably higher in patients with IPAH compared to those with MCTD-PH. Furthermore, within the IPAH group, FeNO levels were found to be lower in cases of severe IPAH compared to mild IPAH (P = 0.024); (2) In severe pulmonary hypertension as per the WHO-FC classification, FeNO levels in IPAH exhibited negative correlations with FEV1/FVC (Forced Expiratory Velocity at one second /Forced Vital Capacity), MEF50% (Maximum Expiratory Flow at 50%), MEF25%, and MMEF75/25% (Maximum Mid-expiratory Flow between 75% and 25%), while in severe MCTD-PH, FeNO levels were negatively correlated with R20% (Resistance at 20 Hz); (3) ROC (Receiving operator characteristic curve) analysis indicated that the optimal cutoff value of FeNO for diagnosing severe IPAH was 23ppb; (4) While FeNO levels tend to be negatively correlated with peakPETO2(peak end-tidal partial pressure for oxygen) in severe IPAH, in mild IPAH they had a positive correlation to peakO2/Heart rate (HR). An interesting find was observed in cases of severe MCTD-PH, where FeNO levels were negatively correlated with HR and respiratory exchange ratio (RER), while positively correlated with O2/HR throughout the cardiopulmonary exercise test.
CONCLUSION
FeNO levels serve as a non-invasive measure of IPAH severity. Although FeNO levels may not assess the severity of MCTD-PH, their significant makes them a valuable tool when assessing severe MCTD-PH.
Topics: Humans; Female; Male; Middle Aged; Adult; Mixed Connective Tissue Disease; Nitric Oxide; Exercise Test; Familial Primary Pulmonary Hypertension; Biomarkers; Respiratory Function Tests; Fractional Exhaled Nitric Oxide Testing; Severity of Illness Index; Hypertension, Pulmonary; Natriuretic Peptide, Brain; China; Aged
PubMed: 38654208
DOI: 10.1186/s12890-024-03004-x