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Las exploraciones funcionales respiratorias ofrecen una amplia gama de técnicas destinadas a la evaluación del funcionamiento del aparato respiratorio. El objetivo de este artículo es presentar los diversos componentes de las pruebas disponibles para evaluar la función respiratoria y su interpretación. En primer lugar, se considera la medición de los volúmenes pulmonares y de los flujos ventilatorios. Estas magnitudes están en el centro de la evaluación funcional básica del sistema respiratorio y permiten, entre otras cosas, identificar y establecer los niveles de gravedad de los trastornos ventilatorios obstructivos y restrictivos. Se basan en la evaluación de los volúmenes pulmonares movilizables (con el espirómetro) y no movilizables (con la pletismografía corporal o una técnica de dilución gaseosa), así como de los flujos ventilatorios (con el neumotacógrafo). Después se analizan los diversos métodos de evaluación de la hiperreactividad bronquial y de la reversibilidad de los trastornos obstructivos. Estas técnicas permiten principalmente la evaluación diagnóstica de los trastornos del espectro del asma. También se examinan las técnicas que permiten una evaluación global de los músculos respiratorios (presiones estáticas máximas, presión inspiratoria nasal) y, de manera más específica, de la función diafragmática (estimulación frénica y medición de la presión transdiafragmática), al igual que las pruebas especializadas que permiten evaluar el control de la ventilación. Por último, el análisis de los gases de sangre se aborda desde un ángulo fisiológico. Esta prueba se utiliza para evaluar la homeostasis gaseosa y acidobásica y para identificar los distintos mecanismos que contribuyen a la hipoxemia (hipoventilación alveolar, cortocircuitos, trastornos de la difusión, alteración de la relación ventilación-perfusión).

Cardiopulmonary exercise testing can be a useful tool for clinicians working with pulmonary hypertension (PH) patients. Exercise magnifies numerous cardiopulmonary decompensations, which can help inform diagnoses, assess degrees of physical impairment, evaluate exertional dyspnea, and estimate prognoses for PH patients. Supervised exercise training also holds promise in PH, because it is safe for patients and feasible and may improve key prognostic outcomes that relate to improvements in quality of life and survival. Still, few clinical trials have evaluated the potential therapeutic effects of exercise training, and future trials may benefit from integrating programming that focuses on light-intensity endurance, strength, and respiratory training.

La dyspnée résulte d’un déséquilibre entre demande (liée à la production métabolique de CO2, au niveau de régulation de PaCO2 et au niveau de ventilation perdue – espace mort physiologique) et capacité (liée au système mécanique respiratoire passif – compliance, résistance – et actif – muscles respiratoires) ventilatoires. La spirométrie et la mesure des volumes pulmonaires statiques n’explorent que la capacité ventilatoire. La demande ventilatoire (augmentée notamment lors des atteintes vasculaires pulmonaires) n’est pas évaluée. La mesure du transfert du CO (DLCO), évaluant à la fois demande et capacité, est l’exploration la plus liée au degré de dyspnée, notamment au cours des pathologies obstructives et interstitielles pulmonaires. La dyspnée, composée de plusieurs dimensions, est intrinsèquement complexe et mal expliquée par les explorations de repos : la variance expliquée n’atteint pas 50 %. La stratégie diagnostique doit distinguer les plaintes en rapport ou non avec l’exercice (il existe des dyspnées sans rapport avec l’effort). L’exploration fonctionnelle à l’exercice avec mesure de V’O2, V’CO2, ventilation (V’E) et volumes pulmonaires dynamiques permet d’apprécier les mécanismes physiopathologiques associés à l’éventuelle limitation de la tolérance à l’effort et peut contribuer à décortiquer les mécanismes physiopathologiques d’une dyspnée mal expliquée même si sa valeur « diagnostique étiologique » reste mal appréciée.

La dyspnée est un symptôme cardinal de l’asthme et constitue un élément essentiel d’évaluation du contrôle de la maladie.

Le prove funzionali respiratorie offrono un’ampia gamma di tecniche destinate alla valutazione della funzionalità dell’apparato respiratorio. Questo articolo ha l’obiettivo di presentare le diverse componenti dei test disponibili per la valutazione della funzione respiratoria e di spiegarne l’interpretazione. In primo luogo è affrontata la misurazione dei volumi polmonari e dei flussi ventilatori. Queste grandezze sono al centro della valutazione funzionale di base del sistema respiratorio e permettono, tra l’altro, di identificare i disturbi ventilatori ostruttivi e restrittivi e di graduarne la gravità. Esse si basano sulla valutazione dei volumi polmonari mobilizzabili (mediante la spirometria) e non mobilizzabili (mediante la pletismografia corporea o una tecnica di diluizione gassosa) nonché dei flussi ventilatori (mediante la pneumotacografia). Sono trattate in seguito le differenti metodiche di valutazione dell’iper-reattività bronchiale e della reversibilità dei disturbi ostruttivi. Queste tecniche consentono principalmente la valutazione diagnostica delle patologie dello spettro dell’asma. Sono discusse anche tecniche che permettono la valutazione globale dei muscoli respiratori (pressioni massimali statiche, sniff test) e più specificamente della funzione diaframmatica (stimolazione frenica e misurazione della pressione transdiaframmatica) così come test specializzati che permettono di valutare il comando ventilatorio. Infine, l’emogasanalisi è affrontata da un punto di vista fisiologico. Questo esame permette allo stesso tempo di valutare l’omeostasi gassosa e acidobasica e di identificare diversi meccanismi che contribuiscono a un’ipossiemia (ipoventilazione alveolare, shunt, disturbi della diffusione, alterazioni dei rapporti ventilazione-perfusione).

Companies in the manufacturing, service and transport infrastructure sectors will play a key role in the sustainable transition of the energy system implementing innovative technologies at full industrial scale. However, developing long-term investment plans is a challenging task, complicated by the volatility of energy markets and the uncertainties induced in the policy landscape by the recent energy crises. In this respect, mathematical models can support the transition of industrial systems, steering the planning process. In this work, we review and evaluate the suitability of available models to serve this purpose. The availability of modelling tools for local energy planning has already been assessed by several works. However, the tools which are most frequently employed at this scale are generally unable to characterise the evolution of the energy system in the long term, they have a focus on the operational aspects of the system, and are, in many cases, proprietary. By contrast, all the models examined in this review are open source, and the investigated set also features tools able to capture long-term dynamics. Our results provide evidence that several tools could offer valuable insights to the planning process. Nevertheless, a trade-off between the representation of long-term dynamics and the modelling of key aspects of the energy system of a company is, to date, inevitable. The best compromise is offered by a small group of multi-scale tools, able to conjugate a long-term perspective with a detailed modelling of the operational aspects of the system.

I test di funzionalità polmonare (TFP) offrono una vasta gamma di tecniche per valutare il funzionamento del sistema respiratorio. Questo capitolo ha l’obiettivo di presentare le diverse componenti dei test disponibili per la valutazione della funzione respiratoria e di spiegarne l’interpretazione. In primo luogo, si comincerà con la misurazione dei volumi polmonari e dei flussi polmonari. Queste grandezze sono al centro della valutazione funzionale di base del sistema respiratorio e permettono, tra l’altro, di identificare i disturbi ventilatori ostruttivi e restrittivi e di classificarne la severità. Si basano sulla valutazione dei volumi polmonari mobilizzabili (utilizzando lo spirometro) e non mobilizzabili (utilizzando la pletismografia corporea o una tecnica di diluizione gassosa) e, anche, dei flussi ventilatori (utilizzando uno penumotacografo). Saranno, poi, affrontati i diversi metodi di valutazione dell’iperreattività bronchiale e della reversibilità dei disturbi ostruttivi. Queste tecniche permettono principalmente la valutazione diagnostica delle malattie all’interno dello spettro asmatico. Saranno discusse tecniche per la valutazione complessiva dei muscoli respiratori (pressioni massime statiche, sniffing test) e, più specificamente, della funzione diaframmatica (stimolazione frenica e misurazione della pressione transdiaframmatica), così come saranno discussi i test specialistici che permettono di valutare il comando ventilatorio. Infine, viene affrontata, da un punto di vista fisiologico, l’emogasanalisi. Questo test permette sia di valutare l’omeostasi gassosa e acidobasica che di individuare i vari meccanismi che contribuiscono all’ipossiemia (ipoventilazione alveolare, shunt, disturbo della diffusione e alterazioni del rapporto ventilazione-perfusione).

Las exploraciones funcionales respiratorias (EFR) ofrecen una amplia gama de técnicas destinadas a la evaluación del funcionamiento del aparato respiratorio. El objetivo de este artículo es presentar los diversos componentes de las pruebas disponibles para evaluar la función respiratoria y su interpretación. En primer lugar se considera la medición de los volúmenes pulmonares y de los flujos ventilatorios. Estas magnitudes están en el centro de la evaluación funcional básica del sistema respiratorio y permiten, entre otras cosas, identificar y establecer los niveles de gravedad de los trastornos ventilatorios obstructivos y restrictivos. Se basan en la evaluación de los volúmenes pulmonares movilizables (con el espirómetro) y no movilizables (con la pletismografía corporal o una técnica de dilución gaseosa), así como de los flujos ventilatorios (con el neumotacógrafo). Después se analizan los diversos métodos de evaluación de la hiperreactividad bronquial y de la reversibilidad de los trastornos obstructivos. Estas técnicas permiten, sobre todo, la evaluación diagnóstica de las patologías del espectro del asma. También se examinan las técnicas que permiten una evaluación global de los músculos respiratorios (presiones estáticas máximas, presión de inhalación nasal máxima) y, de manera más específica, de la función diafragmática (estimulación frénica y medición de la presión transdiafragmática), al igual que las pruebas especializadas que permiten evaluar el control de la ventilación. Por último, los gases de la sangre se estudian desde un punto de vista fisiológico. Esta prueba permite evaluar la homeostasis gaseosa y ácido-base e identificar los mecanismos que contribuyen a una hipoxemia (hipoventilación alveolar, cortocircuitos, trastorno de la difusión, alteraciones de las relaciones ventilación-perfusión).

L’obésité a un effet direct sur la mécanique respiratoire. Les personnes obèses présentent une altération de certains volumes pulmonaires, de la compliance thoracique, et du comportement respiratoire. La dyspnée est un symptôme fréquemment ressenti et limitant pour les sujets obèses. L’objectif de cet article est de clarifier l’impact de l’obésité sur les différents aspects de la mécanique respiratoire, au repos et à l’effort. Obesity directly affects respiratory mechanics. Obese subjects usually show changes in certain lung volumes, respiratory compliance, and respiratory behaviour. Dyspnea is the limiting symptom usually experienced by these subjects. The aim of this review is to clarify the impact of obesity on different aspects of respiratory mechanics, at rest and during exercise.

This review focuses on sensory-perceptual and affectiveemotional domains of dyspnea.

La dyspnée semble peu rapportée au cours des pneumopathies causées par le coronavirus 2 du syndrome respiratoire aigu sévère (SARS CoV 2), faisant parfois évoquer le terme d’“hypoxémie silencieuse”. La dyspnée, perception d’informations sensorielles liées à la respiration, est associée à un vécu émotionnel négatif. Elle résulterait de l’activation de structures du système limbique/paralimbique dont, l’insula. Cette dernière serait le centre d’alarme intéroceptif, reliant la perception de sensations viscérales (dont la dyspnée) à l’expérience consciente des émotions. Le potentiel neuroinvasif du SARS CoV 2 via les bulbes olfactifs fait suspecter une atteinte limbique/paralimbique mais aussi du tronc cérébral au cours de l’atteinte respiratoire de la Corona VIrus Disease 2019 (COVID19). Nous formulons l’hypothèse qu’une atténuation de la composante affective de la dyspnée lors de l’hypoxie, résultant de l’atteinte de l’intéroception, est la conséquence d’une atteinte de ces structures neurologiques.

Les troubles respiratoires (TbR) sont peu décrits chez les patients atteints de SEP, bien qu’ils jouent un rôle primordial dans le fardeau de la maladie. Première cause de mortalité, ils peuvent subitement s’aggraver, en cas d’infection pulmonaire par exemple.

Abstract: The incidence of hip dislocation after primary total hip arthroplasty (THA) has been reported to range from 1 to 25% in THA revision. Here, we explore the hypothesis that there is a correlation between postoperative ileus (POI) and THA dislocation, with POI after THA possibly representing a sentinel event. We retrospectively identified a cohort of 529 consecutive patients who underwent hip arthroplasty from 2008 to 2010. Of them, 251 were male and 278 were female, and a mean average for age of 71.5 (range 65–76). In particular, 19 THA patients showed signs of gastrointestinal complications, and therapeutic consultation was performed with the onset of the first intestinal symptom. Of these 19 patients, 3 THA patients developed POI within 1 week after surgical treatment. A conservative treatment was practised and it seemed to improve the condition: canalization returned and all patients were discharged from the hospital. Unfortunately, two of these patients were readmitted after 2 weeks due to THA dislocation and they underwent THA revision and were discharged from the hospital 7 days later. Follow-up revealed no further problems at 6 months. Our clinical experience with these post-THA primary ileus patients raises the possibility that intra-abdominal symptoms represent a sentinel event in THA dislocation. THA dislocation using neuronal pathway of immunomodulation may modulate POI. Since the risk of THA dislocation is the greatest in the first 3 months after hip arthroplasty, the surgeon should be familiar with the relationship between THA and various pelvic and visceral complications to ensure that POI remains only a rare complication.

Restrictive lung disease is a broad term encompassing a number of conditions in which lung volumes are reduced. Dyspnea is a common clinical manifestation of restrictive lung disease and frequently becomes a prominent and disabling symptom that undermines patients' ability to function and engage in activities of daily living (especially in those with more advanced restriction). Effective management of this disabling symptom awaits a better understanding of its underlying physiology. In recent decades, our understanding of the mechanisms of dyspnea in restrictive lung disease has been improved by a small, but significant, body of research. One approach to the study of dyspnea is to identify the major qualitative dimensions of the symptom in an attempt to uncover different underlying neurophysiologic mechanisms. This article will review the existing literature on the intensity and qualitative dimensions of dyspnea during exercise in patients with restrictive lung disease. The main focus will be on interstitial lung disease (ILD), since it is the prototypical restrictive disease.

Dyspnea and exercise limitation are the dominant symptoms of patients with chronic obstructive pulmonary disease (COPD) and progress relentlessly as the disease advances. Effective management of these disabling symptoms awaits a better understanding of their underlying physiology. Recent research has identified a number of physiological mechanisms that can be targeted for therapeutic manipulation. Thus, interventions that improve dynamic ventilatory mechanics during exercise or reduce ventilatory demand (relative to capacity) will consistently improve exertional symptoms and physical performance even in patients with severe COPD. In this review we will attempt to provide a physiological construct to explain how modern bronchodilator therapy effectively relieves dyspnea and improves exercise endurance in COPD. We will then discuss new advances in our understanding of how oxygen enrichment of the inspired air results in impressive improvements of exertional symptoms and exercise performance even in patients without significant activityinduced arterial oxygen desaturation. Finally, we will demonstrate how combining therapies that improve airflow dynamics with those that alter the central neural drive to breathe have additive and clinically meaningful benefits in patients with advanced COPD.

The inability to engage in the usual activities of daily living is one of the most distressing experiences of people afflicted with chronic obstructive pulmonary disease (COPD). Exercise intolerance progresses relentlessly as the disease advances, contributing to reduced quality of life. It has become clear that in COPD, exercise intolerance ultimately reflects complex integrated abnormalities of the ventilatory, cardiovascular, peripheral muscle and neurosensory systems that vary in degree from patient to patient. Ventilatory limitation and perceived respiratory difficulty are often the dominant contributors to exercise curtailment in more advanced disease, but not necessarily the only ones. Recently, there has been great interest in the role of cardiovascular and peripheral muscle dysfunction (and their interaction) in exercise limitation in COPD. In this review, we examine in some detail the pathophysiological derangements that are evident during exercise in COPD with the hope of identifying specific mechanisms that are amenable to therapeutic manipulation.