2.6. Assessments (Primary, Secondary Outcomes)
bacterial superinfections
DISEASE, DISEASE, BACTERIAL INFECTION
Data were obtained from patient electronic and paper medical records by a critical care physician. Data collection included demographic data, comorbidities, vaccination status, chronic therapy, vitamin D levels on admission, disease severity markers (arterial partial pressure of oxygen/fraction of inspired oxygen ratio (PaO25-OH vitamin D serum levels are not routinely measured in all ICU patients. For the purpose of this study, vitamin D levels were measured in a hospital laboratory using the ECLIA method (Elecsys Vitamin D total III kit; Roche Diagnostics, Diegem, Belgium). Vitamin D levels for patients included in this study were measured on admission to the ICU, and for patients randomized into the intervention group, vitamin D levels were checked on days 7 and 14 of ICU or hospital stay. For patients in the control group, no further vitamin D levels were measured.Disease severity markers were collected daily during ICU stay and every third day after discharge from ICU. Assessment for bacterial superinfections included taking blood, urine and tracheal aspirations for microbiology testing. Samples were taken upon admission, on day 5, and further based on clinical and laboratory signs of possible bacterial infection. In case of patients discharge from hospital before the 28-day period, patients were contacted by phone on day 28 and day 60.