Respiratory Muscle Function and Exercise Performance in Adult Patients with Fontan Circulation.

At rest, a good Fontan circulation can provide a normal cardiac output (CO). However, as a consequence of its unique hemodynamic nature, the limitations of the Fontan circuit are exposed during exercise. We aimed to provide a comprehensive assessment of the pathophysiology of exercise in adult Fontan patients (FPs) and identify factors limiting their functional capacity (FC). In a single-center study conducted in 37 FPs aged ≥16 years and 19 healthy-controls (HCs) who underwent CPET on a cycle ergometer in February and March 2022, the mean peakVO2 was 21 ± 5.4 mL/kg/min, which was 55% of the predicted value. Morphologically, the left single ventricle showed a higher peakVO2% predicted value (57.4 ± 14.4% vs. 43.4 ± 8.1%, p = 0.045). The factors associated with low peakVO2 values were an early flattened or descending O2 pulse at maximal exertion (52 ± 14% vs. 62 ± 12.5, p = 0.04 and 47.6 ± 9% vs. 60 ± 14, p = 0.018, respectively) and chronotropic insufficiency (53 ± 12% vs. 69.8 ± 20%, p = 0.008). The OUES was found to be a useful parameter to assess the FC in FPs in maximal and submaximal exercise testing. A strong positive correlation was observed between the %OUES and peakVO2%predicted (r = 0.726, p > 0.001). The lung function was impaired in the FPs, mostly with a mild restrictive pattern (56.8%). The FPs showed lower inspiratory muscle strength compared to the HCs but it was not statistically associated with either the peakVO2 or VE/VCO2 slope. Regular intense physical activity improves one's FC. Although FPs have inspiratory muscle weakness, its impact on their FC is unclear. The peakVO2% predicted grew progressively higher as the level of physical activity increased (low level 49.5 ± 14%, moderate level 55 ± 12%, intense level 69 ± 20%).

Determinants of oxygen uptake and prognostic factors in cardiopulmonary exercise test in patients with Fontan surgery.

INTRODUCTION: Cardiopulmonary exercise test (CPET) allows quantification of functional capacity of patients with Fontan. The objective of this study was to determine the role of CPET parameters in predicting a higher maximum oxygen consumption (VO2 max) and to analyse the role of CPET parameters in predicting an unfavourable outcome. METHODS: A retrospective, cross-sectional, descriptive study was carried out on 57 patients with Fontan, who had undergone incremental CPET with cycloergometer between 2010 and 2020. Determinants of VO2 max and determinants of clinical deterioration were analysed. RESULTS: In the univariate analysis, the variables significantly related to VO2 max were: age, sex, body mass index (BMI), years of Fontan evolution, intracardiac Fontan, oxygen consumption at anaerobic threshold (VO2AT), CO2 equivalents at anaerobic threshold (VE/VCO2) and chronotropic insufficiency. The multiple linear regression model that best fitted the relationship between VO2 max and independent variables (correlation coefficient 0.73) included sex (correlation index 3.35; p = 0.02), BMI (-0.27; p = 0.02), chronotropic failure (-2.79; p = 0.01) and VO2AT (0.92; p < 0.0001). In the univariate analysis of the prognostic CPET variables related to an unfavourable clinical situation, significance was only obtained with chronotropic insufficiency (p = 0.003). In multivariate analysis, chronotropic insufficiency maintains its association [p= 0.017, OR = 4.65 (1.3-16.5)]. CONCLUSIONS: In conclusion, together with the anthropometric parameters universally related to VO2 max, chronotropic insufficiency and VO2AT are the main determinants of functional capacity in patients with Fontan. Moreover, chronotropic insufficiency is closely related to unfavourable clinical evolution. Our data would support the intensive treatment of chronotropic insufficiency in order to improve the quality of life and the clinical situation of patients with Fontan.

Effects of genetics and altitude on lung function.

OBJECTIVES: The aim of this work is to present a review on the impact of genetics and altitude on lung function from classic and recent studies. DATA SOURCE: A systematic search has been carried out in different databases of scientific studies, using keywords related to lung volumes, spirometry, altitude and genetics. RESULTS: The results of this work have been structured into three parts. First, the relationship between genes and lung function. Next, a review of the genetic predispositions related to respiratory adaptation of people who inhabit high-altitude regions for millennia. Finally, temporary effects and long-term acclimatisation on respiratory physiology at high altitude are presented. CONCLUSIONS: The works focused on the influence of genetics and altitude on lung function are currently of interest in terms of studying the interactions between genetic, epigenetic and environmental factors in the configuration of the pathophysiological adaptation patterns.

Smart Bioimpedance Spectroscopy Device for Body Composition Estimation.

The purpose of this work is to describe a first approach to a smart bioimpedance spectroscopy device for its application to the estimation of body composition. The proposed device is capable of carrying out bioimpedance measurements in multiple configurable frequencies, processing the data to obtain the modulus and the bioimpedance phase in each of the frequencies, and transmitting the processed information wirelessly. Another novelty of this work is a new algorithm for the identification of Cole model parameters, which is the basis of body composition estimation through bioimpedance spectroscopy analysis. Against other proposals, the main advantages of the proposed method are its robustness against parasitic effects by employing an extended version of Cole model with phase delay and three dispersions, its simplicity and low computational load. The results obtained in a validation study with respiratory patients show the accuracy and feasibility of the proposed technology for bioimpedance measurements. The precision and validity of the algorithm was also proven in a validation study with peritoneal dialysis patients. The proposed method was the most accurate compared with other existing algorithms. Moreover, in those cases affected by parasitic effects the proposed algorithm provided better approximations to the bioimpedance values than a reference device.

Smart Vest for Respiratory Rate Monitoring of COPD Patients Based on Non-Contact Capacitive Sensing.

In this paper, a first approach to the design of a portable device for non-contact monitoring of respiratory rate by capacitive sensing is presented. The sensing system is integrated into a smart vest for an untethered, low-cost and comfortable breathing monitoring of Chronic Obstructive Pulmonary Disease (COPD) patients during the rest period between respiratory rehabilitation exercises at home. To provide an extensible solution to the remote monitoring using this sensor and other devices, the design and preliminary development of an e-Health platform based on the Internet of Medical Things (IoMT) paradigm is also presented. In order to validate the proposed solution, two quasi-experimental studies have been developed, comparing the estimations with respect to the golden standard. In a first study with healthy subjects, the mean value of the respiratory rate error, the standard deviation of the error and the correlation coefficient were 0.01 breaths per minute (bpm), 0.97 bpm and 0.995 (p < 0.00001), respectively. In a second study with COPD patients, the values were −0.14 bpm, 0.28 bpm and 0.9988 (p < 0.0000001), respectively. The results for the rest period show the technical and functional feasibility of the prototype and serve as a preliminary validation of the device for respiratory rate monitoring of patients with COPD.

Increased levels of soluble ICAM-1 in chronic obstructive pulmonary disease and resistant smokers are related to active smoking.

AIM: Serum ICAM-1 (sICAM-1) is known to be a smoking-associated inflammatory marker, but data in chronic obstructive pulmonary disease (COPD) are lacking. PATIENTS & METHODS: A total of 142 COPD cases (48 active smokers) and 55 controls (41 active smokers) were consecutively enrolled in this cross-sectional study. The peripheral blood concentrations of sICAM-1, IL-8 (CXCL8), CRP and serum amyloid A (SAA) were determined by ELISA. RESULTS: CRP and SAA (log-scale) were elevated in the patients with COPD compared with the control subjects (p = 0.005 for CRP and p = 0.024 for SAA). sICAM-1 was associated with active smoking when corrected for age, gender, the presence of COPD, inhaled corticosteroid use, BMI and forced expiratory volume in 1 s as covariates. CONCLUSION: The present study confirms an association between sICAM-1 levels and active smoking in a group of COPD and non-COPD active smokers.

Entrenamiento al ejercicio en pacientes con patología respiratoria crónica / No disponible

No disponible

[Hepatopulmonary syndrome in patients with advanced hepatic disease: study of a series of 24 cases]. / Síndrome hepatopulmonar en pacientes con hepatopatía avanzada: estudio de 24 casos.

BACKGROUND AND OBJECTIVE: To describe the characteristics observed in patients diagnosed of hepatopulmonary syndrome (HPS) waiting for orthotopic liver transplantation and those who underwent liver trasplantation. PATIENTS AND METHOD: An observational prospective descriptive study was carried out of patients waiting for liver transplantation in whom data of liver illness and lung function tests were analyzed. RESULTS: 107 patients of 53.69 years average age were studied (7.7 standard deviation). 24 of them (22.4%) had criteria of HPS. Ortodeoxia was present in the 34% of cases. The lung function tests were normal. In the comparative study between patients with HPS and no HPS, differences in diffusion were found (7.1 vs. 8.6 mmol/min/kPa; p = 0.04), as well as in the shunt (8% vs. 5.3%; p = 0.05) and the forced expiratory volume in one second (2,390 vs. 2,743 ml; p = 0.03). Seven patients were transplanted with correction of oxygenation and vascular dilatations in all of them. CONCLUSIONS: HPS is a frequent illness in patients waiting for orthotopic liver transplantation. The main alteration in the blood oxygenation seems owe to shunt, and the diffusion tests is the analysis that could best differentiate patients with HPS. Orthotopic liver transplantation corrects the syndrome in all cases.

Síndrome hepatopulmonar en pacientes con hepatopatía avanzada: estudio de 24 casos / Hepatopulmonary syndrome in patients with advanced hepatic disease: study of a series of 24 cases

Fundamento y objetivo: Describir las características clínicas y funcionales de pacientes con síndrome hepatopulmonar (SHP) en lista de espera para trasplante ortotópico hepático y los cambios producidos en ellas en un grupo de pacientes que recibió el trasplante. Pacientes y método: Se ha realizado un estudio observacional, transversal y descriptivo con carácter prospectivo de pacientes en lista de espera para trasplante hepático, en quienes se analizaron datos de enfermedad hepática y de pruebas de función respiratoria. Resultados: Se ha estudiado a 107 pacientes, con una edad media (desviación estándar) de 53,69 (7,7) años, de los que 24 (22,4%) cumplían criterios de SHP. La ortodesoxia estaba presente en el 34% de los pacientes. Las pruebas de función respiratoria estaban dentro de la normalidad. En el estudio comparativo entre los pacientes afectados de SHP y el resto se encontraron diferencias en la difusión de monóxido de carbono (7,1 frente a 8,6 mmol/min/kPa; p = 0,04), la cuantía del cortocircuito pulmonar (un 8 frente al 5,3%; p = 0,05) y el volumen espiratorio forzado en el primer segundo (2.390 frente a 2.743 ml; p = 0,03). En 7 pacientes con SHP que recibieron el trasplante se corrigieron la oxigenación y las dilataciones vasculares. Conclusiones: El SHP es una entidad frecuente en pacientes en espera de trasplante ortotópico hepático. La principal alteración en la oxigenación sanguínea parece ser debida al efecto cortocircuito. Las pruebas de difusión de monóxido de carbono son las que parecen tener mayor carácter discriminativo entre los pacientes con y sin SHP. Tras el trasplante desaparece el síndrome en todos los pacientes

Background and objective: To describe the characteristics observed in patients diagnosed of hepatopulmonary syndrome (HPS) waiting for orthotopic liver transplantation and those who underwent liver trasplantation. Patients and method: An observational prospective descriptive study was carried out of patients waiting for liver transplantation in whom data of liver illness and lung function tests were analyzed. Results: 107 patients of 53.69 years average age were studied (7.7 standard deviation). 24 of them (22.4%) had criteria of HPS. Ortodeoxia was present in the 34% of cases. The lung function tests were normal. In the comparative study between patients with HPS and no HPS, differences in diffusion were found (7.1 vs. 8.6 mmol/min/kPa; p = 0.04), as well as in the shunt (8% vs. 5.3%; p = 0.05) and the forced expiratory volume in one second (2,390 vs. 2,743 ml; p = 0.03). Seven patients were transplanted with correction of oxygenation and vascular dilatations in all of them. Conclusions: HPS is a frequent illness in patients waiting for orthotopic liver transplantation. The main alteration in the blood oxygenation seems owe to shunt, and the diffusion tests is the analysis that could best differentiate patients with HPS. Orthotopic liver transplantation corrects the syndrome in all cases