[Cardiopulmonary interactions in the course of mechanical ventilation]. / Interactions cœur­poumons au cours de la ventilation mécanique.

INTRODUCTION: The haemodynamic consequences of ventilation are multiple and complex and may affect all the determinants of cardiac performance such as heart rate, preload, contractility and afterload. These consequences affect both right and left ventricle and are also related to the biventricular interdependence. STATE-OF-THE-ART: Ventilation modifies the lung volume and also the intrathoracic pressure. Variations in lung volume have consequences on the pulmonary vascular resistance, hypoxic pulmonary vasoconstriction and ventricular interdependence. Variations in intrathoracic pressure have a major impact and affect systemic venous return, right ventricular preload, left ventricular preload, right ventricular afterload, left ventricular afterload and myocardial contracility. The haemodynamic consequences of positive pressure ventilation depend on the underlying chronic cardiopulmonary pathologies leading to the acute respiratory failure that was the indication for ventilation. CONCLUSION: In this review, we will focus on severe COPD exacerbation, acute left heart failure and weaning from ventilation.

[The French translation and cultural adaptation of the SRI questionnaire. A questionnaire to assess health-related quality of life in patients with chronic respiratory failure and domiciliary ventilation]. / Traduction française et adaptation culturelle du questionnaire SRI. Questionnaire de qualité de vie liée à la santé des patients insuffisants respiratoires chroniques traités par ventilation à domicile.

INTRODUCTION: We performed the French translation and cross-cultural adaptation of the Severe Respiratory Insufficiency (SRI) questionnaire. Written and validated in German, this questionnaire evaluates health-related quality of life in patients treated with domiciliary ventilation for chronic respiratory failure. METHODS: Four bilingual German-French translators and a linguist were recruited to produce translations and back-translations of the questionnaire constituted of 49 items in seven domains. Two successive versions were generated and compared to the original questionnaire. The difficulty of the translation and the naturalness were quantified for each item using a 1-10 scale and their equivalence to their original counterpart was graded from A to C. The translated questionnaire was finally tested in a pilot study, which included 15 representative patients. RESULTS: The difficulty of the first translation and the first back-translation was respectively quantified as 2.5 (range 1-5.5) and 1.5 (range 1-6) on the 10-point scale (P=0.0014). The naturalness and the equivalence of 8/49 items were considered as insufficient, which led to the production of a second translation and a second back-translation. The meanings of two items needed clarification during the pilot study. CONCLUSION: The French translation of the SRI questionnaire represents a new instrument for clinical research in patients treated with domiciliary ventilation for chronic respiratory failure. Its validity needs to be tested in a multicenter study.

[Domiciliary ventilation in patients with COPD]. / Ventilation à domicile chez les patients atteints de bronchopneumopathie chronique obstructive (BPCO).

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) has become one of the main indications for domiciliary ventilation, which is usually non-invasive (NIV). This review focuses on the pathophysiology processes and clinical trial data that underlie current guidelines from international societies. STATE OF THE ART: To date most published studies about domiciliary ventilation in COPD have been short-term and their message is complicated by the presence of significant methodological problems. The two controlled studies of > or =12 months-duration both found that survival was not improved by long-term NIV. Domiciliary ventilation may be considered when long-term oxygen therapy is unsuccessful and when failed with a progressive deterioration in clinical respiratory status with recurrent episodes of acute hypercapnic respiratory failure. A diurnal PaCO(2) > or =55 mmHg (7.3 kPa) is a necessary but not sufficient condition to consider domiciliary ventilation. CONCLUSION: Domiciliary ventilation should only be initiated in selected patients on the basis of clinical symptoms and exacerbation frequency. Until further characterization of patients who are likely to respond, the response to treatment should be assessed regularly.

Dependency on mask ventilation after acute respiratory failure in the intermediate care unit.

The predictive factors for long-term dependency (LTD) on noninvasive ventilation (NIV) immediately after acute hypercapnic respiratory failure (AHRF) have not been identified. The present authors studied 42 patients with chronic obstructive pulmonary disease (COPD) and 58 non-COPD patients successfully treated by NIV for an AHRF episode. Parameters at stable state, at admission for AHRF and during a 1-yr follow-up were compared in patients with or without LTD-NIV at discharge. The incidence of LTD-NIV was 39% in non-COPD patients and 19% in COPD patients. Based on multivariate analysis with stepwise logistic regression, lower baseline pH values and noninfectious causes of AHRF were independently associated with LTD-NIV. Mutually adjusted odds ratios were found to be 1.316 (95% confidence interval (CI) = 1.127-1.536) for a 0.01 decrease of baseline pH value and 5.1 (95% CI = 1.8-14.0) for a noninfectious cause of AHRF. Outcome after 1 yr was poor in COPD patients. Long-term dependency on noninvasive ventilation is not an uncommon situation after resolution of an acute hypercapnic respiratory failure episode, especially in patients with non-chronic obstructive pulmonary disease causes of respiratory failure. The present study raises the need for prospective validation of a weaning protocol in patients managed by noninvasive ventilation for an acute hypercapnic respiratory failure episode.