Davide Nicolotti

Respiratory weaning after cardiac surgery can be difficult or prolonged in up to 22.7% of patients. The inability to wean from a ventilator within the first 48 h after surgery is related to increased short- and long-term morbidity and mortality. Risk factors are mainly non-modifiable and include preoperative renal failure, New York Heart Association, and Canadian Cardiac Society classes as well as surgery and cardio-pulmonary bypass time. The positive effects of pressure ventilation on the cardiovascular system progressively fade during the progression of weaning, possibly leading to pulmonary oedema and failure of spontaneous breathing trials. To prevent this scenario, some parameters such as pulmonary artery occlusion pressure, echography-assessed diastolic function, brain-derived natriuretic peptide, and extravascular lung water can be monitored during weaning to early detect hemodynamic decompensation. Tracheostomy is considered for patients with difficult and prolonged weaning. In such cases, optimal patient selection, timing, and technique may be important to try to reduce morbidity and mortality in this high-risk population.

Acquired thrombotic thrombocytopenic purpura (TTP) is an autoimmune disease that can be triggered by different events, including viral infections. It presents as thrombotic microangiopathy and can lead to severe complications that often require management in the intensive care unit (ICU). We report a patient who presented with acquired TTP following COVID-19 infection. A 44-year-old woman presented to the emergency department with severe anemia, acute kidney injury and respiratory failure due to COVID-19. Clinical and laboratory findings were suggestive for thrombotic microangiopathy. On day 8 laboratory tests confirmed the diagnosis of acquired TTP. The patient needed 14 plasma exchanges, treatment with steroids, rituximab and caplacizumab and 18 days of mechanical ventilation. She completely recovered and was discharged home on day 51. Acquired TTP can be triggered by different events leading to immune stimulation. COVID-19 has been associated with different inflammatory and auto-immune diseases. Considering the temporal sequence and the lack of other possible causes, we suggest that COVID-19 infection could have been the triggering factor in the development of TTP. Since other similar cases have already been described, possible association between COVID and TTP deserves further investigation.