Search Results (289)

Our earlier studies have revealed the beneficial impact of vitamin D3 (VD3) metabolites on the development of pulmonary fibrosis in a murine model of hypersensitivity pneumonitis (HP). Despite the discovery of the great antifibrotic potential of both the bioactive form of VD3, 1,25(OH)₂-VD3 and its direct precursor, 25(OH)-VD3, study designs based on the co-administration of VD3-metabolites and fibrosis-inducers do not reflect the clinical situation. Thus, the presented study aims to examine the effectiveness of therapeutic interventions based on the mentioned inhalations, initiated during the acute phase of HP at the first signs of pulmonary fibrosis. The research was performed using VD3-deficient mice with HP, while VD3-sufficient mice were used as the main control. The data were collected after 28 days of daily exposure of the mice to a fibrosis-inducer (an antigen of Pantoea agglomerans, a well-known etiological factor in HP), with 25(OH)-VD3 or 1,25(OH)₂-VD3 administered daily during the last 14 days of the experiment. The effect of the intervention was monitored by whole-body plethysmography, histological assessment, flow cytometry, RealTime-PCR, and ELISA. Treatment with VD3 metabolites initiated during the acute phase of HP alleviated the disease courses and restored respiratory function, thanks to inhibition of pathological extracellular matrix deposition, immune-cell infiltration of lung parenchyma, profibrotic cytokine production, and EMT progression. Despite the discovery of the beneficial features of the investigated VD3-based therapies, none of them caused full recovery in mice with HP. Nevertheless, after verification in additional animal models and a deeper understanding of the underlying molecular mechanisms, the identified beneficial features of the investigated metabolites have the potential to serve as a foundation for future therapies for HP fibrosis. Full article

Electrical bioimpedance (BioZ) has emerged as a promising technique for the non-invasive monitoring of physiological parameters, owing to its ability to map functional activity into electrical changes. Particularly, impedance plethysmography (IPG) is used to track blood volume changes associated with cardiac activity. However, developing flexible, low-cost devices with enough sensitivity to serve as high-precision for IPGs remains an open challenge. In this work, we introduce laser-induced graphene (LIG) electrodes as an attractive alternative for IPG measurements. The electrodes were fabricated by generating LIG on a polyimide substrate using a 405 nm laser diode and were subsequently characterized morphologically, structurally, and electrically to produce a wrist-worn cardiac impedance sensor (WCIS). The design of the WCIS is based on interdigitated electrodes to detect IPG variations at the radial artery, from which the heart rate is estimated. We show experimental results on IPG signal analysis and its validation against electrocardiogram (ECG) signals as the gold standard. As a result, a mean absolute error (MAE) of 1.7 bpm, a root mean square error (RMSE) of 2.1 bpm, and a limit of agreement of approximately $\pm 6$ bpm were obtained. These outcomes demonstrate the feasibility of the WCIS as a promising, low-cost alternative for continuous, non-invasive cardiovascular monitoring in portable devices, based on the IPG principle. Full article

The growing demand for wearable and Internet of Medical Things (IoMT) devices is driving the development of compact, low-power platforms for continuous physiological monitoring. Bioimpedance analysis represents a versatile non-invasive technique for the assessment of tissue properties, body composition, and respiratory dynamics. This work presents a comprehensive experimental validation of a compact bioimpedance measurement platform based on the SENSIPLUS chip, a CMOS sensor interface integrating a frequency-programmable lock-in amplifier for Electrochemical Impedance Spectroscopy in the 10 kHz–1 MHz range. The platform was validated at three complementary levels: (i) electrical characterization on Debye tissue-equivalent circuits using a three-point bilinear calibration, with analysis of the electrode–skin contribution and repeatability assessment; (ii) in vivo multi-frequency bioimpedance spectroscopy (BIS) with Cole–Cole model fitting and hook-effect correction; and (iii) single-frequency thoracic impedance plethysmography for respiratory monitoring. Results were compared against an Agilent E4980A precision Inductance (L), Capacitance (C), and Resistance (R) meter and a calibrated spirometer. The presented device achieved a maximum resistance error below 5.7% and reactance deviation under 6 $\mathsf{\Omega }$ across the investigated frequency range, Cole–Cole parameters consistent with reference values, and strong linear correlation ($R^2=0.97$) between thoracic impedance variations and tidal volume, with respiratory rate estimation errors below 2% across the ten sessions, specifically 1.43% during normal breathing and 1.96% during deep breathing. These results demonstrate that the SENSIPLUS-based platform achieves metrological performance compatible with the requirements of wearable IoMT applications, here demonstrated in a single-subject proof-of-concept study, while relying for all critical analog functions on a compact ($1.5\times 1.5$) mm² system-on-chip with low power consumption (1.5 mW). Full article

Intraoperative monitoring systems play a vital role in surgical safety and decision-making. This study explored whether high-resolution physiological signals routinely available during surgery can be leveraged by deep learning to predict adverse events after head and neck free flap reconstruction. In this retrospective study, intraoperative waveforms, including arterial pressure, plethysmography, and electrocardiogram, from 187 patients who underwent free flap surgery were analyzed. A deep learning model based on the Mamba architecture was trained to predict three outcomes: flap failure, return to the operating room for exploration, and other surgical complications. Conventional logistic regression using static clinical variables and feature-based machine learning models were evaluated for comparison. On a patient-wise stratified held-out test set, the deep learning model achieved AUROCs of 0.86, 0.62, and 0.93 for flap failure, re-exploration, and other complications, respectively. Precision was 0.50, 0.40, and 1.00, whereas recall was 0.50, 0.40, and 0.25, indicating high precision but modest recall. Predictive performance varied across outcomes. These findings demonstrate the feasibility of waveform-based deep learning for perioperative risk stratification in reconstructive surgery, although the preliminary nature, limited sample size, and lack of external validation should be considered. Full article

Although poverty and tuberculosis are insidiously linked, knowledge of the relationship between social determinants of health (SDoHs) and post-tuberculosis lung disease (PTLD) is limited. This study aimed to analyze the association between physical function, pulmonary function, and SDoHs in individuals with PTLD (iwPTLD), considering the impact of social inequalities on physical performance. This cross-sectional study collected social data from 69 iwPTLDs using a standardized assessment form. The patients underwent pulmonary function testing via spirometry and body plethysmography, as well as respiratory muscle strength and quadriceps muscle strength (QMS) testing. They also completed the six-minute step test (6MST). The median value of steps climbed by participants on the 6MST was 88 (57–117), corresponding to 50.1% (34.9–73.2) of the predicted value. The mean QMS was 28.7 ± 11.9 kgf, with 11 participants (17.4%) showing QMS below the cutoff point. Spirometry revealed normal, obstructive, restrictive, and mixed patterns in 19 (27.5%), 20 (29%), 18 (26.1%), and 12 (17.4%) of the participants, respectively. Performance on the 6MST showed no statistically significant association with SDoHs. QMS showed a statistically significant association with treated sewage (W = 84, p = 0.026). Forced expiratory volume in one second showed significant correlations with education level (ρ = 0.248, p = 0.040), social protection (W = 207, p = 0.050, r = 0.238), and treated water (W = 24.5, p = 0.029, r = 0.264). Maximum inspiratory pressure showed significant correlations with education level (ρ = 0.246, p = 0.042) and treated water (W = 20, p = 0.021, r = 0.280). The regression model for 6MST and QMS performance showed that 12% and 45% of the variability was explained by the studied variables, respectively. In iwPTLD, impairments in physical function and damage to lung function are weakly associated with the deterioration of SDoHs. While this relationship is weak, it should not be ignored because it may operate through indirect pathways. Full article

Background/Objectives: Opioids inhibit breathing that can lead to fatal overdose, highlighting the need for testing effective countermeasure agents and potential mechanisms of action. Here we examined the role muscarinic cholinergic receptors play in the ability of L-cysteine ethyl ester (L-CYSee) to overcome the deleterious effects of morphine on ventilatory parameters in male Sprague Dawley rats and the ventilatory responses during a subsequent hypoxic-hypercapnic (HH) challenge. Methods: Ventilatory parameters were measured by whole body plethysmography. Results: The injection of the muscarinic receptor antagonist, atropine (1.0 mg/kg, IV), elicited an array of ventilatory responses (e.g., an increase in frequency of breathing coupled with a fall in tidal volume). Injection of morphine (10 mg/kg, IV) to vehicle-treated rats elicited a depression of breathing, including sustained decreases in tidal volume, minute ventilation, peak inspiratory flow, and peak inspiratory and expiratory drives, which were associated with marked increases in end inspiratory pause (EIP) and end expiratory pause (EEP), expiratory flow at 50% expired tidal volume (EF₅₀), and rate of achieving peak expiratory flow (Rpef). Most effects of morphine (10 mg/kg, IV) were not altered in atropine-treated rats, except that increases in EIP, EEP and Rpef were reduced. Subsequent injections of L-CYSee (2 × 500 μmol/kg, IV given 15 min apart) overcame the adverse actions of morphine on ventilatory parameters in vehicle-treated rats. The effects of L-CYSee, such as reversal of the effects of morphine on frequency of breathing, tidal volume and minute ventilation, were markedly reduced in atropine-treated rats. The ability of L-CYSee to reverse the adverse effects of morphine to a HH gas challenge was markedly diminished in atropine-treated rats. Conclusions: These findings demonstrate that muscarinic receptors play a vital role in the ability of L-CYSee to overcome the deleterious effects of morphine. Full article

Background/Objectives: We examined the role of muscarinic cholinergic receptors in the ventilatory depressant effects of morphine in male Sprague Dawley rats, and in responses elicited by a hypoxic-hypercapnic gas (HH) challenge and upon return to room air. Methods: Ventilatory parameters were measured in freely moving rats by whole body plethysmography that continuously recorded these parameters. Results: The injection of morphine (10 mg/kg, IV) elicited a relatively pronounced depression of breathing, including sustained decreases in tidal volume, minute ventilation, peak inspiratory flow, and inspiratory and expiratory drives that were associated with marked increases in end inspiratory pause (EIP), expiratory flow at 50% expired tidal volume (EF₅₀), and the rate of achieving peak expiratory flow (Rpef). Subsequent injection of the muscarinic receptor antagonist, atropine (1 mg/kg, IV), in morphine-treated rats did not affect the frequency of breathing, tidal volume, minute ventilation, inspiratory and expiratory times, end expiratory pause, peak inspiratory and expiratory flows, relaxation time, expiratory delay, apneic pause, inspiratory and expiratory drives, and the non-eupneic breathing index (p > 0.05 for all comparisons). In contrast, atropine dramatically reduced the morphine-induced increases in EIP, Rpef and EF₅₀ (p < 0.05, for all comparisons). In addition, the changes in many ventilatory parameters (e.g., frequency of breathing, tidal volume and minute ventilation) that occurred during a subsequent HH-challenge and upon the return to room air were markedly reduced in atropine-treated rats (p < 0.05, for all comparisons). Conclusions: These findings suggest that muscarinic receptors play a limited, but important role, in the expression of the ventilatory effects of morphine in male rats and a substantial role in the expression of responses elicited during and following HH-challenge. Full article

Aims: Globally, cardiovascular disorders represent the foremost contributor to mortality, and elevated arterial pressure constitutes one of their principal risk determinants. Despite the availability of various treatments, optimal blood pressure control is rarely achieved. The present work was undertaken to assess the antihypertensive and vasorelaxant properties of benzaldehyde, a naturally occurring aromatic aldehyde whose role in the regulation of arterial pressure has, to our knowledge, not yet been documented. Materials and Methods: Antihypertensive activity was evaluated in normotensive Wistar rats and in animals rendered hypertensive by chronic administration of Nω-nitro-L-arginine methyl ester (L-NAME). Benzaldehyde was administered orally at doses of 20 and 40 mg/kg under both acute (6 h) and subacute (7-day) treatment protocols. Arterial pressure was recorded non-invasively by means of a tail-cuff plethysmography system. Vasorelaxant activity was examined in vitro using isolated rat aortic rings precontracted with either Epinephrine (EP, 10 μM) or potassium chloride (KCl, 80 mM). Endothelium-dependent and endothelium-independent components were dissected by pre-incubating the rings with selective pharmacological inhibitors. Additionally, the effects of benzaldehyde on both phasic and tonic contractions induced by extracellular Ca²⁺ were assessed in EP-precontracted rings in Ca²⁺-free Krebs solution. Key Findings: In hypertensive animals, benzaldehyde produced a dose-related decrease in both systolic and diastolic arterial pressure. It induced concentration-dependent vasorelaxation in both endothelium-intact and -denuded aortic rings. Relaxation was also observed in KCl-precontracted rings. Vasorelaxant responses were significantly attenuated by Indomethacin, Nifedipine, and 2-Aminoethoxydiphenyl borinate (2-APB). Significance: These findings demonstrate that benzaldehyde lowers blood pressure through both endothelium-dependent and -independent mechanisms. These include activation of the prostacyclin (PGI₂)/cAMP pathway, inhibition of L-type calcium channels, and blockade of store-operated calcium channels (SOCCs). Full article

Background/Objectives: Airway inflammation and small airway dysfunction (SAD) are key features of asthma. Inflammation can be assessed by blood eosinophil count (Eos) and exhaled nitric oxide (NO) parameters, including fractional exhaled nitric oxide (FeNO), bronchial NO flux (J’awNO), and alveolar NO concentration (CANO), the latter reflecting distal airway inflammation. We aimed to evaluate the association between Eos and the degree of airway inflammation as specified by exhaled NO parameters and to assess the relationships between exhaled NO parameters and small airway dysfunction using spirometric and plethysmographic indices. Methods: We conducted an observational study of asthmatic outpatients who underwent spirometry, plethysmography, and exhaled NO measurements. Multivariable regression models were used to estimate associations between Eos and FeNO, J’awNO, CANO, and spirometric/plethysmographic indices, adjusting for age, sex, body mass index, and relevant covariates. Results: The analytic cohort included 121 patients (49 men; 72 women; median age 54.2 years). Small airway obstruction and a range of airway inflammation severity were observed. Mean (SD) or median [IQR] values, as appropriate, were: FEF₇₅ z-score −0.62 (0.96); FEF_25–75 z-score −1.27 (1.29); RV z-score 1.26 (0.94); RV/TLC z-score 1.60 (1.10); J’awNO 60.20 nL/min (102.80); FeNO 23.61 ppb (37.61); CANO 3.80 ppb (4.12); and Eos 260 cells/µL (430). Log-transformed Eos (log[Eos]) was associated with FeNO, J’awNO, and CANO (adjusted marginal slope [95% CI]: 12.11 [9.35–14.69], 33.56 [25.34–41.19], and 1.14 [0.84–1.43], respectively). Log(Eos) was also positively associated with RV and RV/TLC, but negatively associated with FEF_25–75, FEF₇₅, and FEV₁. Similarly, CANO was positively associated with RV and RV/TLC and inversely associated with FEF_25–75 and FEF₇₅. No significant associations were observed for FeNO or J’awNO. Conclusions: Blood eosinophils were independently associated with all exhaled NO parameters. The association between CANO and small airway ventilatory function indices supports a link between distal airway inflammation and SAD in asthma. Full article

Background/Objectives: Obesity remains difficult to treat effectively, not because weight loss cannot be achieved, but because it is difficult to sustain in the face of physiological adaptations to energy restriction, including reductions in resting metabolic rate and loss of fat-free mass. Dietary strategies that preserve favorable body composition while supporting long-term adherence are therefore needed. The purpose of this study was to compare continuous caloric restriction (CCR) with an intermittent approach incorporating structured diet refeeds and planned diet breaks (DRF) on body composition outcomes in adult women with obesity. Methods: Thirty adult females (18–65 years; BMI 30–45 kg·m⁻²) were randomized to 12 weeks of CCR or DRF following a two-week maintenance phase used to determine individualized caloric needs. Both groups were prescribed a 25% caloric deficit and protein intake of 1.2 g·kg⁻¹·day⁻¹. Body composition, including body fat percentage, fat mass, and fat-free mass, was assessed using air-displacement plethysmography at baseline and post-intervention. Results: Repeated-measures ANOVA revealed a significant main effect of time for body fat percentage (p < 0.001), which decreased by 6.7 ± 2.1% in the CCR group and 6.0 ± 1.9% in the DRF group, with no significant group × time interaction (p > 0.05). Fat mass significantly declined in both groups (p < 0.001), with reductions of 9.30 ± 2.77 kg (CCR) and 9.21 ± 2.63 kg (DRF); between-group differences were negligible (p > 0.05; Cohen’s d = 0.03). Fat-free mass increased over time (p < 0.05); although the interaction was not significant (p = 0.08), the DRF group demonstrated a moderate effect size advantage. Despite similar changes in body composition, analysis of energy balance revealed a significantly greater daily energy deficit in the CCR group compared with DRF (−1005 ± 515 vs. −690 ± 120 kcal·day⁻¹, p = 0.041), indicating a higher achieved level of caloric restriction in CCR. Conclusions: Both dietary strategies effectively reduced fat mass in females with obesity; however, incorporating diet breaks was associated with a nonsignificant trend toward greater preservation or accrual of fat-free mass without compromising fat loss. Future studies should investigate this potential association in larger, adequately powered trials before any conclusions regarding metabolic adaptation or practical advantage can be drawn. Full article

Introduction: Emphysema is frequently observed in patients with fibrosing interstitial lung diseases (f-ILDs), leading to the clinical entity known as combined pulmonary fibrosis and emphysema (CPFE). This study aimed to evaluate the utility of airwave oscillometry (AOS) in detecting small-airway dysfunction (SAD) in patients with CPFE. Due to the coexistence of both restrictive and obstructive airway disease, spirometry is comparatively less sensitive in detecting airflow limitations in this population. Methods: A cohort of 52 patients with CPFE was recruited from Monaldi Hospital, Naples, between January and September 2023. Pulmonary function tests—including spirometry, body plethysmography, and single-breath diffusing capacity for carbon monoxide (DLCO)—were performed at baseline and following bronchodilator administration. Patients with normal FEV1/FVC ratios underwent airwave oscillometry (AOS) to assess respiratory system resistance (Rrs) and reactance (Xrs), with SAD defined as an R5–R19 value greater than 0.07 kPa·s·L⁻¹. Results: AOS-defined SAD was present in 40.4% (21/52) of the cohort. The R5–R19 value in the SAD group was 0.13 ± 0.05 kPa·s·L⁻¹, which can be compared to 0.04 ± 0.02 kPa·s·L⁻¹ in patients without SAD. Patients with SAD were more likely to be undergoing maintenance bronchodilator therapy (16/21; 76.2%) than those without SAD (8/31; 25.8%) (p = 0.015). Fourteen CPFE patients met the criteria for bronchial responsiveness. CPFE patients who responded to bronchodilators had lower R5-R19 values than non-responders (0.04 ± 0.02 vs. 0.09 ± 0.06 kPa·s·L⁻¹; p = 0.04). Discussion: Although AOS parameters did not significantly change following bronchodilator administration, this study underscores the value of AOS in detecting peripheral airway dysfunction, which may be under-recognized by conventional spirometry. Conclusions: AOS shows promise as a diagnostic adjunct for identifying SAD in CPFE patients and may complement standard pulmonary function testing in clinical practice. Further multicenter studies with larger cohorts are warranted to validate these findings and investigate the longitudinal impact of SAD on disease progression and treatment outcomes in CPFE. Full article

Background: The breathing cycle consists of abdominal breathing (AB), for which the diaphragm is responsible, and thoracic breathing (TB), generated by the intercostal muscles. Contraction of the two portions of the diaphragm accounts for 80% percent of inspiration. While bilateral diaphragmatic paralysis causes severe shortness of breath, hemidiaphragm paralysis (HDP) gives fewer symptoms at rest, making it difficult to recognize and diagnose. Because this condition is rare, little is known regarding its consequences on breathing efficiency. Hypothesis: Based on previous studies, we hypothesized that body positions substantially affect the efficiency of breathing in a patient with unilateral hemidiaphragm paralysis and the corresponding physiological parameters. Aims: To measure and compare the amplitudes of abdominal and chest movements in different body positions in an individual with HDP and measure parameters indicating breathing efficiency. Patient and Methods: The patient had HDP due to iatrogenic phrenic nerve injury. Changes in the circumference of the abdomen and chest were measured during inhalation and exhalation with respiratory plethysmography belts (placed on standardized reproducible positions on the chest and abdomen) in different body positions: sitting (SI), standing (ST), lying (SU) and prone (PR). Breathing frequency was calculated, and blood oxygen saturation (SpO₂) was measured with a pulse oximeter. Results: The percentage (%) contributions of abdominal breathing were SI: 16.0; ST: 50.3; SU: −53.5; PR: 1.1. A negative sign shows paradoxical breathing. Blood oxygen saturation (SpO₂) in the four positions was SI: 93%; ST: 93%; SU: 82%; and PR: 82%, whereas the respiratory rate (1/min) was SI:19.4; ST: 15.0; SU: 37.5; PR: 35.9. Conclusions: Body position markedly influences the relative contributions of abdominal and thoracic breathing and overall respiratory efficiency in patients with hemidiaphragm paralysis; abdominal breathing in the supine and prone positions is greatly reduced leading to decreased blood oxygen saturation, a compensatory increase in respiratory rate, and severe dyspnea even at rest. Full article

Preterm birth interrupts critical phases of lung development and is associated with long-term alterations in respiratory structure and function. While bronchopulmonary dysplasia (BPD) has traditionally been considered the principal determinant of adverse outcomes, accumulating evidence indicates that prematurity per se contributes substantially to persistent pulmonary impairment. Lung function trajectories in preterm-born children frequently track along lower percentiles from infancy into adolescence and early adulthood, with limited catch-up growth and increased vulnerability to chronic airflow limitation. Assessment of lung function requires a developmentally tailored approach, as feasibility and interpretability vary across age groups. In infancy, non-volitional techniques such as tidal breathing flow-volume loop analysis and raised-volume rapid thoracoabdominal compression allow early evaluation of respiratory mechanics. During toddlerhood, methodological limitations persist, although emerging technologies may expand feasibility. In preschool children, impulse oscillometry enables detection of small airway dysfunction, often preceding spirometric abnormalities. From school age onward, spirometry, body plethysmography, diffusing capacity, and multiple breath washout provide complementary information on obstructive, restrictive, and gas-exchange impairments. Longitudinal studies demonstrate that reduced lung function is not confined to children with BPD and may predispose to early-onset chronic obstructive pulmonary disease-like phenotypes. Early identification of abnormal trajectories and modifiable risk factors supports structured long-term follow-up and preventive strategies. Standardization of age-specific assessment protocols and harmonization of reference values are essential to improve risk stratification and optimize long-term respiratory outcomes in this vulnerable population. Full article

Background/Objectives: The aim of this study was to assess whether preoperative pulmonary function testing (PFT) is related to postoperative complications after open thoracoabdominal aortic aneurysm (TAAA) repair. Methods: This study was conducted as a retrospective cohort analysis of 205 patients undergoing open TAAA repair (2006–2024) with preoperative spirometry and body plethysmography with at least one value available. Patients were classified by ventilation patterns: obstructive (n = 85, 45.2%), restrictive (n = 26, 14.1%), and hyperinflation (n = 56, 30.3%). Primary endpoints included in-hospital mortality, pulmonary complications (pneumonia, ARDS), and multi-organ outcomes. Associations were analyzed using chi-square and Spearman correlation tests and multivariable linear regression adjusted for age, smoking status, COPD, emergency operation, and time period. Results: Postoperative pulmonary complications occurred in 126 patients (61.5%), including pneumonia (46.8%) and ARDS (15.1%). Reduced vital capacity and FEV₁ expressed as a percentage of the lower limit of normal (%LLN) were related to postoperative pneumonia (p = 0.031 and p = 0.003) and ARDS (p = 0.038). Both obstructive and restrictive ventilation patterns were related to acute kidney injury after surgery (all KDIGO stage) (p = 0.044 and p = 0.043, respectively). Hyperinflation was related to atrial fibrillation (p = 0.039) and stroke (p = 0.034). FEV₁ < 2.0 L was related to increased mortality risk (p = 0.037), and FEV₁ < 1.5 L predicted acute kidney injury (p = 0.017), spinal cord ischemia (p = 0.035), and mortality (p = 0.023). Prolonged mechanical ventilation correlated with reduced preoperative lung function (VC %LLN ρ = −0.288, p = 0.002; FEV₁ %LLN ρ = −0.286, p = 0.001). During median follow-up of 6.35 years, patients in the highest FEV₁ quartile demonstrated substantially reduced long-term mortality (HR 0.27, 95% CI 0.10–0.73, p = 0.01). These associations between lower FEV₁ and VC (expressed as %LLN) with pneumonia, ARDS, in-hospital mortality, and prolonged ventilation remained significant after multivariable analysis. Conclusions: Preoperative pulmonary function assessment may help identify TAAA patients at increased risk of postoperative complications and mortality. Combining percentage-predicted spirometry, ventilation patterns, and hyperinflation markers may support individualized treatment selection, prehabilitation, and perioperative monitoring based on each patient’s specific risk profile. Full article

Objectives: To confirm the utility of barometric whole-body plethysmography (BWBP) as a non-invasive, clinical diagnostic test for brachycephalic obstructive airway syndrome (BOAS) in cats. Methods: Client-owned cats belonging to brachycephalic breeds were enrolled and classified into two clinical severity grades of upper airway obstruction (UAO). Brachycephalic cats with high-grade UAO severity (Brachy-H-UAO) represented those with clinically evident effects on clinical signs or physical examination findings, whereas brachycephalic cats with low-grade UAO severity (Brachy-L-UAO) represented those without clinically evident problems. A group of non-brachycephalic (NB) cats that were respiratory disease-free and with neither a history of cardiac or systemic diseases nor exposure to cigarette smoke was used as the control group. Cats were placed in the BWBP chamber, and breathing signals were obtained after an adaptation period in a quiet and silent environment. The ventilatory variables obtained were respiratory rate (RR; [bpm]), tidal and minute volume per kilogram bodyweight (MV/BW and TV/BW; [mL/kg]), inspiratory (Ti; [s]) and expiratory (Te; [s]) intervals, airway obstruction index enhanced pause (Penh), and peak inspiratory and expiratory flows per kilogram (PIF and PEF; [mL/s/kg]). Results: Forty-three client-owned cats (11 Brachy-H-UAO, 7 Brachy-L-UAO, and 25 NB) were included. Brachycephalic cats (Brachy-H-UAO: 311 mL/kg; Brachy-L-UAO: 253 mL/kg) showed significantly lower median MV/BW than NB cats (503 mL/kg) (p = 0.01). Brachy-H-UAO cats demonstrated significantly higher median PEF/PIF ratios (Brachy-H-UAO: 1.46, minimum–maximum 0.82–2.48; Brachy-L-UAO: 0.76, 0.52–1.11; NB: 0.73, 0.56–1.00) and Penh (Brachy-H-UAO: 2.37, minimum–maximum 0.57–23.82; Brachy-L-UAO: 0.57, 0.27–1.11; NB: 0.53, 0.21–0.68) than Brachy-L-UAO and NB cats (p < 0.001). No significant differences were observed among the three groups for RR, TV/BW, Ti, Te, or Te/Ti. Conclusions and Relevance: Cats affected by BOAS demonstrate impaired ventilatory function, with reduced minute ventilation and a distinctive flow pattern and parameters reflecting limited inspiratory flow and increased upper airway resistance. BWBP can serve as a useful tool to diagnose and characterize the severity of BOAS in cats. Full article