RESUMEN
BACKGROUND: More and more patients have obesity-hypoventilation syndrome (OHS) because of the increasing prevalence of obesity. The accuracy of transcutaneous PCO2 (PtcCO2 ) has recently been validated. However, no study evaluated the interest of measuring systematically nocturnal PtcCO2 in the follow-up of patients with OHS and home mechanical ventilation to detect residual nocturnal hypoventilation. We aimed to evaluate the contribution of nocturnal PtcCO2 to assess nocturnal hypoventilation compared with current routine examinations, that is, daytime arterial blood gases and nocturnal pulse oximetry. METHODS: A prospective monocentric pilot study was conducted from August 2018 to November 2019. Patients with stable OHS and who were treated with home noninvasive ventilation for at least 6 months were eligible to participate. After oral consent, we performed both diurnal arterial blood gases and combined home oximetry and capnography. The primary end point was the presence of residual nocturnal hypoventilation, defined as PaCO2 > 45 mm Hg or bicarbonate ≥ 27 mmol/L, SpO2 < 90% for ≥ 10% of the night, or PtcCO2 > 49 mm Hg for ≥ 10% of the night. RESULTS: A total of 32 subjects were included. Twenty-nine subjects with nocturnal PtcCO2 were analyzed. Eighteen of the 29 subjects showed residual nocturnal hypoventilation. The association of diurnal arterial blood gases and nocturnal pulse oximetry revealed nocturnal hypoventilation in only 9 subjects. Among the 19 subjects with both normal blood gases and normal nocturnal pulse oximetry, 11 had nocturnal hypoventilation with transcutaneous capnography. Only one subject presented with hypoventilation symptoms (asthenia). CONCLUSIONS: The assessment of PtcCO2 in comparison with nocturnal pulse oximetry and arterial blood gases provides important information for the diagnosis of residual nocturnal hypoventilation in the subjects with OHS who were ventilated at home.
RESUMEN
BACKGROUND: Lung transplantation (LT) is an identified risk factor for Pneumocystis pneumonia (PCP). However, PCP management and outcomes remain poorly described in LT recipients and PCP incidence is rarely documented in this population. METHODS: PCP episodes that occurred in 9 French LT centers between January 2010 and October 2017 were included in this analysis. PCP was defined as compatible clinical and radiologic findings associated with fungal identification. RESULTS: Forty-seven PCP were included. The annual incidence rate of PCP was 2.7/1000 patients/year. Patients had a mean age of 53 ± 14 years. Median time from LT was 2.4 ± 3.0 years. Sixty-five percent of patients were not on prophylaxis at the time of PCP while all patients were receiving steroids at the time of PCP. Diagnosis was obtained by bronchoalveolar lavage in 91% (direct examination: 47%, PCR: 62%). The majority of patients were treated with trimethoprim-sulfamethoxazole (78%). Fifty-five percent of patients were hospitalized in ICU for organ failure (for which non-invasive ventilation was used for 21% and mechanical ventilation for 23%). Mortality rate was 15% at day 28 and reached 23% at day 90. Mortality was associated with decreased FEV1, everolimus treatment, Pseudomonas aeruginosa coinfection, fungal coinfection (especially Aspergillus sp.), mechanical ventilation and vasopressors. PCP primary prophylaxis, steroid modification during PCP and the number of immunosuppressive molecules were not associated with mortality. CONCLUSION: PCP is associated with a high mortality in LT. Our data suggest the need for a lifetime PCP prophylaxis in LT recipients. The benefit of adjuvant steroids remains unclear.