Simulated ventilation of two patients with a single ventilator in a pandemic setting.

Simultaneous ventilation of two patients may lead to hypoventilation in one patient and hyperinflation in the other patient. In a simulation of ventilation in two patients using artificial lungs, we voluntarily directed gas flow to one patient by using three-dimensional-printed Y-adapters and stenosis adapters during volume- and pressure-controlled ventilation in the first set up. We continuously modified the model using a special one-way valve on the flow-limited side and measured it in pressure-controlled ventilation with the flow sensor of the ventilator adjusted on both sides in a second and third setup. In the first setup, volume- or pressure-controlled ventilation resulted in comparable minute volumes in both lungs, even when one side was obstructed to 3 mm. In the second setup, with a 3-mm flow limitation, we had a minute ventilation of 9.4 ± 0.3 vs. 3.5 ± 0.1 L/min. In the third setup, ventilation with a 3-mm flow limitation resulted in minute ventilation of 7.2 ± 0.2 vs. 5.70 L/min at a compliance of 30 vs. 70 mL/mbar. It is possible to override the safety features of a modern intensive care ventilator and thus direct tidal volumes in different lung conditions to one lung using three-dimensional-printed flow limiters. While this ventilation setting was technically feasible in a bench model, it would be unstable, if not dangerous, in a clinical situation.

Cardiac involvement in patients with rheumatic disorders: Data of the RHEU-M(A)R study.

BACKGROUND: The diagnosis of cardiac involvement in rheumatic disorders is challenging due to its varying clinical presentation. Since clinical consequences range from immediate treatment changes to adverse long-term outcome, individual risk stratification is of great clinical interest. Primary aim was to evaluate the prevalence of cardiac involvement in patients with different rheumatic disorders using late gadolinium enhancement-cardiac magnetic resonance imaging (LGE-CMR). In addition, we sought to investigate if different rheumatic disorders would demonstrate different LGE patterns. METHODS: Two-hundred-ninety-seven patients with rheumatic disorders were included and underwent LGE-CMR for work-up of cardiac involvement, which was defined by the presence of LGE in the myocardium. Patients were divided into five subgroups: 1) ANCA-associated vasculitis, 2) non-ANCA-associated vasculitis, 3) connective tissue disorders, 4) arthritis, and 5) sarcoidosis. RESULTS: Mean ejection fraction in the overall population was 65%, with a mean age of 55yrs. Prevalence of cardiac involvement in the five subgroups were as follows: 54% in the ANCA-associated vasculitis group, 22% in the non-ANCA-associated vasculitis group, 14% in the group with connective tissue disorders, 21% in the arthritis group, and 24% in sarcoid patients. Each of the five subgroups demonstrated a distinct pattern of LGE. CONCLUSION: There is a wide range in the prevalence of cardiac involvement in different rheumatic disorders (54%-14%). Different groups of rheumatic disorders demonstrate different patterns of LGE. CONDENSED ABSTRACT: Primary aim of the study was to evaluate the presence of cardiac involvement in patients with different rheumatic disorders using LGE-CMR. In addition, we sought to investigate if different rheumatic disorders would reveal different LGE patterns. In our 297 patients, the highest prevalence of cardiac involvement was found in patients with ANCA-associated vasculitis (54%), whereas the lowest prevalence was demonstrated in patients with connective tissue disorders (14%). Furthermore, different groups of rheumatic disorders demonstrate distinct patterns of LGE.