Characteristics of influenza pneumonia patients admitted to the ICU due to hypoxemic respiratory failure.

Introduction: Hypoxemic respiratory failure due to influenza pneumonia during epidemic seasons sometimes may require mechanical ventilation support and intensive care unit (ICU) stay. We aimed to evaluate the characteristics and risk factors of influenza pneumonia patients admitted to our ICU due to hypoxemic respiratory failure.

Materials And Methods: Patients admitted to our ICU between December 2015 and March 2016 who had hypoxemic respiratory failure due to clinically and radiologically suspected influenza pneumonia were enrolled.

Result: Twenty two patients (11 male) met the enrollment criteria. Median age and APACHE II score was 45 (36-63) years and 19 (13-25) respectively. Maximum set PEEP levels during mechanical ventilation was significantly lower in patients who survived [10 (8-10) vs 13 (10-16), p= 0.025)]. Deceased patients spent more time under a PaO2/FiO2 ratio below 100 [72 (24-90) vs. 0 (0-48) hours, p= 0.024]. Survival rate was 88% (7/8) in patients who had noninvasive ventilation (NIV) success while it was only 7% (1/14) in patients who had undergone invasive mechanical ventilation (p< 0.001). Overall mortality was 64%.

Conclusions: Viral pneumonia may result in severe hypoxemic respiratory failure and ARDS especially during epidemic seasons. NIV success, time spent under a PaO2/FiO2 ratio below 100 and low serum albumin levels at admission may be predictors of severity of the disease and mortality.