Prognostic factors of respiratory worsening after admission in otherwise normal patients with respiratory syncytial virus infection

Abstract

Objective: Respiratory syncytial virus (RSV) infection sometimes causes respiratory failure after hospital admission, even if respiratory function seems normal on admission. We investigated initial risk factors of RSV infection in otherwise normal patients to predict respiratory worsening. Methods: We reviewed the clinical records of 87 patients with RSV infection admitted to the Yodogawa Christian Hospital between January 2011 and September 2013. We divided patients into the ventilated group and the control group according to their need for ventilatory support including noninvasive positive pressure ventilation and continuous negative mode of biphasic cuirass ventilation after admission, and we retrospectively analyzed characteristics, present medical conditions, and diagnostic tests. Results: A multivariable logistic regression analysis identified venous bicarbonate and abnormal findings on chest X-ray as independent risk factors for ventilatory support after admission. Conclusion: Normal patients with RSV infection who have the elevated bicarbonate on initial venous blood gas analysis or abnormal findings on chest X-ray (e.g., infiltration, atelectasis, or hyperinflation) may require ventilatory support after admission with careful monitoring.