Predictor factors for non-invasive mechanical ventilation failure in severe COVID-19 patients in the intensive care unit: a single-center retrospective study

Abstract

Background During the COVID-19 pandemia, non-invasive mechanical ventilation (NIV) has been largely applied. Few data are available about predictors of NIV failure in critical COVID-19 patients admitted to ICU. The aim of this study is to analyze clinical and laboratory features able to predict non-invasive ventilation success in avoiding endotracheal intubation. Methods A retrospective observational study was performed in our COVID-19 ICU during a 6-month period. Demographic, clinical, laboratory, imaging, and outcome data were extracted from electronic and paper medical records and anonymously collected. Results Eighty-two severe COVID-19 patients were supported by NIV at ICU admission. The median PaO2/FiO2 ratio was 125 [98.5–177.7]. NIV failed in 44 cases (53%). Patients who experienced NIV failure had a higher Charlson Comorbidity Index (median value 4) compared to those who were dismissed without endotracheal intubation (median 2, p < 0.0001). At Cox regression analysis, the Charlson Comorbidity Index represented a predictive factor related to NIV failure. PaO2/FiO2, CPK, INR, and AT III at ICU admission showed a significant relationship with the outcome, when single variables were adjusted for the Charlson Comorbidity Index. Conclusion The Charlson Comorbidity Index may be helpful to stratify patients’ risk of NIV failure in a severe COVID-19 population; even if this study, retrospective design does not allow definitive conclusions.

Krebs von den Lungen 6 (KL-6) levels in COVID-19 ICU patients are associated with mortality

“…Lorenzoni et al [ 20 ], through a machine learning approach for predicting ICU mortality in COVID-19 patients, proved that age was the leading predictor, followed by total SOFA score at ICU admission, and the P/F used for SOFA calculation. In our previous experience [ 21 ] and in the present study too, patients’ characteristics at ICU admission severely conditionate the success of advanced therapeutic strategies. In this paper, when SOFA score is higher than 5, prognosis is already compromised, and consequently, the prognostic power of KL-6 is reduced, while it can still be helpful to identify lung injury in patients with a lower organ failure score ( SOFA < 5).…”

Factors related to mortality of patients with COVID-19 who are admitted to the ICU: Prognostic mortality factors of COVID-19 patients

“…This is expected to be associated with greater hypoxemia and lower oxygen saturation in the peripheral pulse wave, reflecting greater hypotension at the hemodynamic level. [28]…”

“…This is expected to be associated with greater hypoxemia and lower oxygen saturation in the peripheral pulse wave, reflecting greater hypotension at the hemodynamic level. [28] In terms of ventilatory support, patients who received highflow nasal oxygen therapy on admission had lower mortality rates, while those who received NIV on admission had higher mortality rates. These results may be due to the fact that in most hospital centers the use of NIV was reserved for the most severely ill patients, whereas virtually all patients requiring ICU admission were started on HFNO therapy.…”