Introduction: Diaphragm thickening fraction (TF) is a marker of disease severity in stable COPD. We investigated the natural evolution of TF during an acute exacerbation (AE) and its predictive value as a marker of early readmission. Methods: We prospectively recruited patients with AECOPD requiring hospitalization. Diaphragm ultrasound was performed at 3 time points: <24h of admission (ADM), at discharge (DIS) and 6-8 weeks after discharge, to assess baseline status (BL). Patients were grouped according to the presence of treatment failure (re-hospitalization for persistent symptoms <30 days of discharge). TF was reported as TFtidal%max (ratio of TF during tidal breathing and during maximal inspiration, representing the contractile requirement of tidal breathing). Results: 28 patients were included (71±9 yrs, FEV1 36±13% predicted). 7 patients had treatment failure. In patients without treatment failure, TFtidal%max decreased from ADM to DIS, and further at BL (51±21% vs 35±18 vs 21±9, all p<0.05). In patients with treatment failure, TFtidal%max did not decrease between ADM and DIS (61±21% vs 62±10%, p=0.98) but decreased at BL (11±2%, p<0.05 compared to DIS). At DIS, TFtidal%max was significantly higher in patients that would need re-admission (p=0.001). In ROC analysis, TFtidal%max at DIS had high predictive value for treatment failure (AUROC 0.92, p=0.001, with a cut-off value of 48% showing 100% sensitivity and 76% specificity). Conclusion: TFtidal%max is increased in AECOPD and is responsive to clinical evolution. Its measurement at discharge is a predictive marker of treatment failure. These findings further support the role of diaphragm ultrasound in the management of COPD.
Prone position has been widely used in the COVID-19 pandemic, with an extension of its use in patients with spontaneous breathing ('awake prone'). We herein propose a review of the current literature on prone position in mechanical ventilation and while spontaneous breathing in patients with COVID-19 pneumonia or COVID-19 ARDS.A literature search retrieved 70 studies separating whether patient was intubated (24 studies) or nonintubated (46 studies). The outcomes analyzed were intubation rate, mortality and respiratory response to prone. In nonintubated patient receiving prone position, the main finding was mortality reduction in ICU and outside ICU setting.The final results of the several randomized control trials completed or ongoing are needed to confirm the trend of these results. In intubated patients, observational studies showed that responders to prone in terms of oxygenation had a better survival than nonresponders.
Early Career Members of Assembly 2 (Respiratory Intensive Care) attended the European Respiratory Society International Congress through a virtual platform in 2021. Sessions of interest to our assembly members included symposia on the implications of acute respiratory distress syndrome phenotyping on diagnosis and treatment, safe applications of noninvasive ventilation in hypoxaemic respiratory failure, and new developments in mechanical ventilation and weaning, and a guidelines session on applying high-flow therapy in acute respiratory failure. These sessions are summarised in this article.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated pneumonia is associated with severe hypoxemic respiratory failure requiring treatment in intensive care units (ICUs) in approximately 5–10% of hospitalized patients. Lung protective mechanical ventilation and intermittent prone positioning are standard care and evidence-based strategies in the management of severe acute respiratory distress syndrome. These strategies are presented in Surviving Sepsis Campaign guidelines for the management of critically-ill adults with coronavirus disease (COVID-19). Prone positioning as a complement to oxygen therapy to treat hypoxemia in COVID-19 pneumonia in spontaneously breathing patients has been widely adopted, despite a lack of evidence for its benefit. The objective of this single-center, cluster-randomised controlled trial is to test the hypothesis that a simple incentive to self-prone would decrease oxygen needs in patients admitted to the ward for COVID-19 pneumonia on low-flow oxygen therapy.
Methods
Twenty-seven patients with confirmed COVID-19 pneumonia admitted to our University Hospital medical ward were included in the study. Ten patients were randomised to self-prone positioning and 17 to usual care.
Main Results
Oxygen needs assessed by oxygen flow on nasal cannula at inclusion were similar between groups. Twenty-four hours after starting the intervention, the median oxygen flow was 1.0 L/min (interquartile range, 0.1–2.9) in the prone position group and 2.0 L/min (interquartile range, 0.5–3.0) in the control group (P = 0.507) (figure 1). Median oxygen saturation/fraction of inspired oxygen ratio was 390 (interquartile range, 300–432) in the prone position group and 336 (interquartile range, 294–422) in the control group (P = 0.633). No serious adverse events were observed.
Conclusions
Self-prone positioning in patients with COVID-19 pneumonia requiring low-flow oxygen therapy resulted in a clinically meaningful reduction of oxygen flow, without reaching statistical significance. Early interruption of the trial after the first wave most probably resulted in underpower of our study. Self-prone positioning was easy to implement and well tolerated. Given the rapid increase of cases during the COVID-19 pandemic, any simple intervention to limit the progression of hypoxemia and avoid transfers of patients to ICUs may be of benefit for the management of hospital resources.
Point-Of-Care Ultrasonography (POCUS) has emerged to support the diagnosis process and management strategies. Its use for the diagnosis of pneumonia has been shown to be reliable and effective over the past decade. Various ultrasonography patterns exist, none of which are pathognomonic for pneumonia. Therefore, POCUS findings must be interpreted in association with the clinical setting. POCUS enables early identification of complications such as parapneumonic effusion and pulmonary abscess. It also provides guidance for invasive procedure such as thoracocentesis and pleural drainage. The forthcoming results of the Swiss OCTOPLUS study will provide data on the clinical and economic impact of a diagnostic strategy based on targeted lung ultrasonography.L’échographie ciblée, aussi connue sous le terme de Point-Of-Care Ultrasonography (POCUS), a émergé comme outil essentiel dans la démarche diagnostique et la stratégie de prise en charge des patients. Son utilisation pour le diagnostic de la pneumonie a été démontrée comme fiable et performante depuis plus d’une décennie. Plusieurs profils échographiques existent mais aucun n’est pathognomonique de la pneumonie. L’examen échographique est ainsi indissociable du contexte clinique. Le POCUS permet en outre la recherche précoce de complications (épanchement parapneumonique et abcès pulmonaire) et le guidage des gestes invasifs (thoracocentèse et drainage thoracique). Les résultats à venir de l’étude suisse OCTOPLUS permettront d’en savoir plus sur l’impact clinique et économique d’une stratégie diagnostique basée sur l’échographie pleuropulmonaire.
Purpose of review: Lung ultrasound is a noninvasive bedside technique that can accurately assess pulmonary congestion by evaluating extravascular lung water. This technique is expanding and is easily available. Our primary outcome was to compare the efficacy of volume status assessment by lung ultrasound with clinical evaluation, echocardiography, bioimpedance, or biomarkers. The secondary outcomes were all-cause mortality and cardiovascular events. Sources of information: We conducted a MEDLINE literature search for observational and randomized studies with lung ultrasound in patients on maintenance dialysis. Methods: From a total of 2363 articles, we included 28 studies (25 observational and 3 randomized). The correlation coefficients were pooled for each variable of interest using the generic inverse variance method with a random effects model. Among the clinical parameters, New York Heart Association Functional Classification of Heart Failure status and lung auscultation showed the highest correlation with the number of B-lines on ultrasound, with a pooled r correlation coefficient of .57 and .36, respectively. Among echocardiographic parameters, left ventricular ejection fraction and inferior vena cava index had the strongest correlation with the number of B-lines, with a pooled r coefficient of .35 and .31, respectively. Three randomized studies compared a lung ultrasound-guided approach with standard of care on hard clinical endpoints. Although patients in the lung ultrasound group achieved better decongestion and blood pressure control, there was no difference between the 2 management strategies with respect to death from any cause or major adverse cardiovascular events. Key findings: Lung ultrasound may be considered for the identification of patients with subclinical volume overload. Trials did not show differences in clinically important outcomes. The number of studies was small and many were of suboptimal quality. Limitations: The included studies were heterogeneous and of relatively limited quality.
Introduction: In patients with cystic fibrosis (CF), the monitoring of respiratory muscle activity using electromyography can provide information on the demand-to-capacity ratio of the respiratory system and act as a clinical marker of disease activity, but this technique is not adapted to routine clinical care. Ultrasonography of the diaphragm could provide an alternative, simpler and more widely available alternative allowing the real-time assessment of the diaphragm contractile reserve (DCR), but its relationship with recognized markers of disease severity and clinical outcomes are currently unknown. Methods: Stable patients with CF were prospectively recruited. Diaphragm ultrasound was performed and compared to forced expiratory volume in 1 s (FEV1), residual volume (RV), handgrip strength, fat-free mass index (FFMI), serum vitamin levels, dyspnea levels and rate of acute exacerbation (AE). Diaphragm activity was reported as DCR (the ratio of tidal-to-maximal thickening fractions, representing the remaining diaphragm contractility available after tidal inspiration) and TFmax (representing maximal diaphragm contractile strength). Inter-observer reliability of the measurement of DCR was evaluated using intra-class correlation analysis. Results: 110 patients were included [61 males, median (interquartile range), age 31 (27-38) years, FEV1 66 (46-82)% predicted]. DCR was significantly correlated to FEV1 (rho = 0.46, p < 0.001), RV (rho = -0.46, p < 0.001), FFMI (rho = 0.41, p < 0.001), and handgrip strength (rho = 0.22, p = 0.02), but TFmax was not. In a multiple linear regression analysis, both RV and FFMI were independent predictors of DCR. DCR, but not TFmax, was statistically lower in patients with > 2 exacerbations/year (56 ± 25 vs. 71 ± 17%, p = 0.001) and significantly lower with higher dyspnea levels. A ROC analysis showed that DCR performed better than FEV1 (mean difference in AUROC 0.09, p = 0.04), RV (mean difference in AUROC 0.11, p = 0.03), and TFmax at identifying patients with an mMRC score > 2. Inter-observer reliability of DCR was high (ICC = 0.89, 95% CI 0.84-0.92, p < 0.001). Conclusion: In patients with CF, DCR is a reliable and non-invasive marker of disease severity that is related to respiratory and extra-pulmonary manifestations of the disease and to clinical outcomes. Future studies investigating the use of DCR as a longitudinal marker of disease progression, response to interventions or target for therapy would further validate its translation into clinical practice.
Introduction: In COPD and critical illnesses, diaphragm ultrasound is a marker of disease severity and clinical outcomes. We report on quantitative values of diaphragmatic ultrasound variables and its predictors in the CF population, which are currently lacking. Methods: CF patients were prospectively recruited. Diaphragm ultrasound was performed and compared to lung function tests, handgrip strength, fat-free mass (FFM), transthyretin, vitamin A, E and D levels, C-reactive protein (CRP), dyspnea levels and rate of acute exacerbation (AE). Diaphragm activity was reported as thickening fraction during maximal inspiration (TFmax, maximal contractile action) and TF%max (ratio of TF during tidal breathing and TFmax, representing contractile requirement of tidal breathing). Results: 110 patients were included [61 males, median (interquartile range) age 31 (27-38) years and FEV1 66 (46-82)% predicted]. Median TFmax was 86 (55-126)% and its lower 5th percentile was 30%. TF%max was not correlated to age, FFM or vitamin levels, but significantly correlated to transthyretin (rho=-0.27, p=0.005), CRP (rho=0.47, <0.001), FEV1 and handgrip strength (both p<0.05). TF%max was significantly higher in patients with >2 AE/year (44±25 vs 29±17, p=0.001), in those with mMRC score >2 (69±15 vs 31±18%, p<0.001) and was a better marker of dyspnea level than FEV1 (AUROC 0.87 vs 0.77, p=0.03). Conclusion: In CF patients, the lower limit of normal for TFmax is 30%. TF%max is related to peripheral strength, markers of systemic inflammation, nutritional status and FEV1, and outperforms FEV1 as a marker of dyspnea levels. This lays the basis for studies evaluating diaphragmatic activity as a marker of prognosis and efficacity of interventions in CF.
