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E Weitzenblum

Publications and source records attributed to E Weitzenblum.

At least 37 records · Page 2Linked to original sources

The obesity-hypoventilation syndrome revisited: a prospective study of 34 consecutive cases.

STUDY OBJECTIVES: Obesity has many detrimental effects on the respiratory function and may lead to chronic hypoventilation in some patients, an association known as the obesity-hypoventilation syndrome (OHS). In many cases, patients with OHS also have sleep apneas. Hereafter, we describe several features of a cohort (n = 34) of patients with OHS and show the comparisons with a large cohort (n = 220) of patients with obstructive sleep apnea syndrome (OSAS). We compare also OHS patients with a group of patients with the association of OSAS and COPD, also known as "overlap" patients. DESIGN: Descriptive analysis of prospectively collected clinical data. SETTING: Respiratory care unit and sleep laboratory of university hospital. RESULTS: In OHS patients, OSAS was present in most of the cases (23 of 26 patients). However, in three patients, OHS was not associated with OSAS, showing that obesity per se may lead to chronic hypoventilation. As expected by definition, OHS patients had, on average the worst diurnal arterial blood gas measurements, compared to the other groups. For the OHS patients, the mean diurnal PaO(2) was 59 +/- 7 mm Hg, which was significantly different from the PaO(2) of the OSAS patients (75 +/- 10 mm Hg; p = 0,001) but also from the overlap patients (66 +/- 10 mm Hg; p = 0.015). Pulmonary hypertension (ie, mean pulmonary artery pressure > 20 mm Hg) was more frequent in OHS patients than in "pure" OSAS patients (58% vs 9%; p = 0.001). CONCLUSION: Patients with OSAS and chronic respiratory insufficiency had in most cases an associated OHS or COPD. Patients with OHS were older than patients with pure OSAS. They had mild-to-moderate degrees of restrictive ventilatory pattern due to obesity. Severe gas exchange impairment and pulmonary hypertension were quite frequent. The association of OHS and OSAS was the rule. However, in three patients, OHS was not associated with OSAS, suggesting that OHS is an autonomous disease.

Chronic Disease↗

Platypnea-orthodeoxia syndrome related to an aortic aneurysm combined with an aneurysm of the atrial septum.

We report the case of a 71-year-old man bearing a severe right-to-left shunt through a patent foramen ovale in the absence of elevated right-sided heart or pulmonary artery pressures. He presented with platypnea-orthodeoxia syndrome, but he had no pulmonary or extracardiac diseases that are known to be associated with this syndrome. Chest radiography showed a bulky aneurysm of the thoracic aorta. A peripheral contrast transesophageal echocardiography demonstrated a large right-to-left shunt through a patent foramen ovale. In addition, the atrial septum was severely deformed by an aneurysm including this patent foramen ovale. We hypothesized that the opening of the foramen ovale was the result of a mechanical deformation of the atrial septum by two contributing factors: the aneurysm of the thoracic aorta and the aneurysm of the septum itself.

Aged↗

Daytime hypoventilation in obstructive sleep apnoea syndrome.

Chronic alveolar hypoventilation is a classic feature of the "pickwickian syndrome" (i.e. obesity-hypoventilation syndrome) but in fact hypercapnia is observed in a minority of obstructive sleep apnoea syndrome (OSAS) patients. Most recent studies having included large numbers of unselected, consecutive OSAS patients agree on a prevalence of 10-20% of alveolar hypoventilation. The mechanisms of hypercapnia in OSAS are not fully understood but the determining factors of daytime respiratory insufficiency are probably the presence of a marked obesity, leading to the obesity hypoventilation syndrome and, principally, the association of OSAS with chronic obstructive pulmonary disease. This association (the so-called "overlap syndrome") is observed in >10% of OSAS patients. Bronchial obstruction is generally mild to moderate and may be asymptomatic. The severity of the nocturnal events (apnoeas, hypopnoeas) and a (possible) diminished chemosensitivity to hypercapnic and hypoxic stimuli do not appear to be determining factors of hypercapnia. The most important consequence of chronic alveolar hypoventilation is pulmonary hypertension which is only observed in patients with daytime arterial blood gases disturbances, and which can lead to right heart failure. When nasal continuous positive airway pressure fails to correct sleep-related hypoxaemia, supplementary O, must be given or another way of assisted ventilation (BIPAP) must be considered. In the most severe patients (diurnal PaO(2) <55 mmHg) conventional O(2) therapy (>or=16h/24h) is required in addition to nocturnal ventilation.

Journal Article↗

Prognostic value of lung function and pulmonary haemodynamics in OSA patients treated with CPAP.

The aim of the present study was to determine survival rates of obstructive sleep apnoea patients treated with continuous positive airway pressure (CPAP) and to investigate the prognostic value of pretreatment lung function and pulmonary haemodynamics. Two hundred and ninety-six patients, exhibiting > or = 20 apnoeas plus hypopnoeas per hour of sleep, were included. Patients were treated with nasal CPAP and regularly followed up. The cumulative survival rates were 0.96 (95% confidence interval (CI): 0.94-0.99) at 3 yrs and 0.93 (95% CI: 0.91-0.97) at 5 yrs. Most patients died from cardiovascular disease. Apart from age, covariates associated with a lower survival were the presence of a heavy smoking history, a low vital capacity, a low forced expiratory volume in one second (FEV1) and a high mean pulmonary artery pressure. Only three covariates were included by forward stepwise selection in the multivariate analysis, smoking habit (>30 pack-yrs), age and FEV1. The observed survival rates of the group as a whole were similar to those of the general population matched in terms of age, sex and smoking habit, except for patients between 50 and 60 yrs old who had reduced survival. This difference disappeared when patients of the present study with an associated chronic obstructive pulmonary disease were excluded from the comparison. In conclusion, survival of obstructive sleep apnoea patients treated with nasal continuous positive airway pressure is near to that of the general population. The prognosis is worse in subgroups of patients with a history of heavy smoking and with an associated chronic obstructive pulmonary disease.

Female↗

Predictive factors of hospitalization for acute exacerbation in a series of 64 patients with chronic obstructive pulmonary disease.

Hospitalizations for acute exacerbation in patients with chronic obstructive pulmonary disease (COPD) have a great impact on health care expenditure. The aim of this study was to look at predictive factors of hospitalization for acute exacerbation in a group of patients with moderate to severe COPD. During the year 1994, we included 64 patients with COPD in this study. At inclusion, the patients being in a stable state, we performed a complete evaluation of their clinical, spirometric, gasometric, and pulmonary hemodynamic characteristics. All patients were followed during a period of at least 2.5 yr. We recorded the intervals free of hospitalization for exacerbation and realized an analysis of the proportional hazards not to be hospitalized using the Kaplan-Meier method. Univariate analysis using the log-rank test showed that the risk of being hospitalized was significantly increased in patients with COPD with a low body mass index (BMI <= 20 kg/m2, p = 0.015) and in patients with a limited 6-min walk distance (<= 367 m, p = 0. 045). But above all, the risk of hospitalization for acute exacerbation was significantly increased by gas exchange impairment and pulmonary hemodynamic worsening: PaO2 <= 65 mm Hg versus PaO2 > 65 mm Hg, p = 0.005; PaCO2 > 44 mm Hg versus PaCO2 <= 44 mm Hg, p = 0.005; and mean pulmonary artery pressure ( Ppa) at rest > 18 mm Hg versus Ppa <= 18 mm Hg, p = 0.0008. Neither age, nor the association of one or more comorbidities with COPD, nor the smoking habits had a significant impact on the risk of hospitalization in our study. Multivariate analysis showed that only PaCO2 and Ppa were independently related to the risk of hospitalization for acute exacerbation of COPD. We conclude that chronic hypercapnic respiratory insufficiency and pulmonary hypertension are predictive factors of hospitalization for acute exacerbation in COPD patients.

Aged↗

A randomized trial of nocturnal oxygen therapy in chronic obstructive pulmonary disease patients.

The beneficial effects of nocturnal oxygen therapy (NOT) in chronic obstructive pulmonary disease (COPD) patients with mild-to-moderate daytime hypoxaemia (arterial oxygen tension (Pa,O2) in the range 7.4-9.2 kPa (56-69 mmHg)) and exhibiting sleep-related oxygen desaturation remains controversial. The effectiveness of NOT in that category of COPD patients was studied. The end points included pulmonary haemodynamic effects after 2 yrs of follow-up, survival and requirement for long-term oxygen therapy (LTOT). Seventy-six patients could be randomized, 41 were allocated to NOT and 35 to no NOT (control). The goal of NOT was to achieve an arterial oxygen saturation of >90% throughout the night. All these patients underwent polysomnography to exclude an associated obstructive sleep apnoea syndrome. The two groups exhibited an identical meansD daytime Pa,O2 of 8.4+/-0.4 kPa (63+/-3 mmHg) at baseline. Twenty-two patients (12 in the NOT group and 10 in the control group, p=0.98) required LTOT during the whole follow-up (35+/-14 months). Sixteen patients died, nine in the NOT group and seven in the control group (p=0.84). Forty-six patients were able to undergo pulmonary haemodynamic re-evaluation after 2 yrs, 24 in the NOT and 22 in the control group. In the control group, mean resting pulmonary artery pressure increased from 19.8+/-5.6 to 20.5+6.5 mmHg, which was not different from the change in mean pulmonary artery pressure in the NOT group, from 18.3+/-4.7 to 19.5+/-5.3 mmHg (p= 0.79). Nocturnal oxygen therapy did not modify the evolution of pulmonary haemodynamics and did not allow delay in the prescription of long-term oxygen therapy. No effect of NOT on survival was observed, but the small number of deaths precluded any firm conclusion. These results suggest that the prescription of nocturnal oxygen therapy in isolation is probably not justified in chronic obstructive pulmonary disease patients.

Follow-Up Studies↗

Improvement of pulmonary hypertension after liver transplantation.

Pulmonary hypertension at the end stage of chronic liver disease is not an uncommon situation. This association termed portopulmonary hypertension raises the question of the feasibility of performing orthotopic liver transplantation (OLT). In the case reported herein, there was a favorable outcome after OLT, even though the mean pulmonary artery pressure (MPAP) before transplantation was increased to 45 mm Hg. Before OLT, the cardiac index (CI) was considerably elevated (7.69 L/min/m2), giving evidence of a marked hyperdynamic circulatory state. The CI decreased significantly after OLT (3.38 L/min/m2), and this produced a significant decrease in the MPAP. Our observation suggests that portopulmonary hypertension due to a marked increase in the CI can be managed successfully by OLT.

Adult↗

[Paraneoplastic hypercorticism associated with a bronchial adenocarcinoma].

Cushing's syndrome is infrequently associated with adenocarcinomas of the lung. We present the clinical features of this syndrome in one case report. The pathogenesis of the syndrome explains the clinical signs, rather different from classical Cushing's disease and also the highly suggestive biological features. Ketoconazole improves clinical signs and biological abnormalities when etiological treatment is not effective.

Adenocarcinoma↗

[Chronic thromboembolic pulmonary arterial hypertension].

Chronic thromboembolic pulmonary hypertension (CTEPH) is an uncommon disease with a severe prognosis. Initially considered as a constantly fatal disease, it can be cured since the advent in the late 80's of thromboendarterectomy. CTEPH occurs in approximately 0.1% of patients who survive acute pulmonary embolism. Such outcome is due to the failure of the normal thrombi resolution in the pulmonary circulation. This disease is observed in both sexes and occasionally as early as in the third decade. Many patients have no history of acute venous thromboembolism which is responsible for the frequent diagnosis delay. Therefore, it is of paramount importance to search for pulmonary vascular disease when patients complain solely of dyspnea on exertion. These patients should undergo echocardiography and, if necessary, right heart catheterization. Once the diagnosis of pulmonary hypertension is established the next step is to find the cause. Ventilation-perfusion scanning is probably the most sensitive non-invasive test to provide evidence that pulmonary hypertension is related to chronic thromboembolism. Angiography and helical computed tomography allow to confirm the diagnosis of CTEPH and to determine whether it is accessible or not to thromboendarterectomy. Most patients who undergo thromboendarterectomy improve clinically and in terms of gas exchange and pulmonary hemodynamics. When thrombi are inaccessible surgically, patients should be placed on the list for lung transplantation if they fulfill the criteria established for primary pulmonary hypertension. When all surgical procedures are contraindicated, anticoagulant and oxygen therapy remain the sole possibility of treatment.

Anticoagulants↗

Antiproliferative properties of human alveolar macrophages.

OBJECTIVE: The aim of our study was to determine whether macrophages from lung cancer patients could acquire antitumoral properties in an in vitro model. METHODS: We isolated macrophages from bronchoalveolar lavages performed in two groups of patients: patients with lung cancer and patients with lung infection. All patients were smokers. We used the inhibition of incorporation of 3H-thymidine by U937 tumoral cells as an in vitro cytostatic assay. RESULTS: When stimulated by gamma interferon, alveolar macrophages either from lung cancer patients or from patients with lung infection induced cytostasis of proliferating U937 tumoral cells. This effect could be reproduced by using the supernatants of cultures of activated macrophages. When using optimal doses, gamma interferon showed an increased activity as compared with lipopolysaccharide. The combination of these two compounds was no more effective than gamma interferon alone in cancer patients. A macrophage/U937 tumoral cell ratio of 1/1 was sufficient to achieve a near-maximal cytostatic effect. CONCLUSIONS: Our results demonstrate that it is possible to activate, in vitro, alveolar macrophages from lung cancer patients by stimulation with gamma interferon. These macrophages acquire antiproliferative properties against a sensitive tumoral cell line.

Bronchoalveolar Lavage Fluid↗