Significance of Hypocapnia in the Risk Assessment of Patients with Pulmonary Hypertension.

Blood gas analysis is part of the diagnostic work-up for pulmonary hypertension (PH). Although some studies have found that the partial pressure of carbon dioxide (PaCO2) is an independent marker of mortality in individuals with pulmonary arterial hypertension (PH Group 1), there is a lack of data regarding the significance of PaCO2 in individuals with different types of PH based on the new 2022 definitions. Therefore, this study analyzed data from 157 individuals who were undergoing PH work-up, including right heart catheterization, using PH definitions from the 2022 European Society of Cardiology/European Respiratory Society guidelines. At diagnosis, N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) levels were significantly higher, but the time-course of NT-pro-BNP levels during treatment was significantly more favorable in individuals with pulmonary arterial hypertension (PH Group 1) who did versus did not have hypocapnia (p = 0.026 and p = 0.017, respectively). These differences based on the presence of hypocapnia were not seen in individuals with PH Groups 2, 3, or 4. In conclusion, using the new definition of PH, hypocapnia may correlate with worse risk stratification at diagnosis in individuals with pulmonary arterial hypertension. However, hypocapnic individuals with pulmonary arterial hypertension may benefit more from disease-specific therapy than those without hypocapnia.

Six Months Follow-Up of Patients with Invasive Mechanical Ventilation due to COVID-19 Related ARDS.

Although patients who recovered from acute coronavirus disease 2019 (COVID-19) may have prolonged disabilities, follow-up data of those who have survived COVID-19 related acute respiratory distress syndrome (ARDS) is still very scarce. Therefore, COVID-19-ARDS survivors requiring invasive mechanical ventilation (IMV) were followed six months after discharge. Pulmonary function tests (PFTs), 6-min walk test (6MWT) and echocardiography were performed. Quality of life (QoL), depression and anxiety were assessed using validated questionnaires. Patients were compared based on respiratory mechanics and CT-phenotype during intensive care unit (ICU) stay. Eighteen patients were included (61 ± 7 years; ICU-stay: 34 ± 16 days; IMV: 30 ± 15 days). At follow-up (197 ± 15 days after discharge), PFTs did not reveal significant limitations (VC: 92 ± 16%; FEV1: 92 ± 20%; DLco/VA: 81 ± 16%). Cardiac systolic function was normal in all patients, but 50% of them had diastolic dysfunction. 6MWT was under the lower limit of normal in only two patients. Eight patients (44%) reported tiredness, six (33%) suffered from fatigue and one patient (6%) had depression and anxiety. Surprisingly, patients with worse respiratory mechanics during IMV reported fewer symptoms and less exertional dyspnea at follow-up. In conclusion, patients with COVID-19-ARDS have the possibility to fully recover regarding pulmonary function and exercise capacity, which seems to be independent of disease severity during ICU stay.

Clinical course of COVID-19 patients needing supplemental oxygen outside the intensive care unit.

Patients suffering from CVOID-19 mostly experience a benign course of the disease. Approximately 14% of SARS-CoV2 infected patients are admitted to a hospital. Cohorts exhibiting severe lung failure in the form of acute respiratory distress syndrome (ARDS) have been well characterized. Patients without ARDS but in need of supplementary oxygen have received much less attention. This study describes the diagnosis, symptoms, treatment and outcomes of hospitalized patients with COVID-19 needing oxygen support during their stay on regular ward. All 133 patients admitted to the RWTH Aachen university hospital with the diagnosis of COVID-19 were included in an observational registry. Clinical data sets were extracted from the hospital information system. This analysis includes all 57 patients requiring supplemental oxygen not admitted to the ICU. 57 patients needing supplemental oxygen and being treated outside the ICU were analyzed. Patients exhibited the typical set of symptoms for COVID-19. Of note, hypoxic patients mostly did not suffer from clinically relevant dyspnea despite oxygen saturations below 92%. Patients had fever for 7 [2-11] days and needed supplemental oxygen for 8 [5-13] days resulting in an overall hospitalization time of 12 [7-20] days. In addition, patients had persisting systemic inflammation with CRP levels remaining elevated until discharge or death. This description of COVID-19 patients requiring oxygen therapy should be taken into account when planning treatment capacity. Patients on oxygen need long-term inpatient care.