INTRODUCTION
Bronchiolitis is a disorder commonly caused by viral lower respiratory tract infection in infants. Signs and symptoms typically begin with rhinitis and cough, which can progress to tachypnea, wheezing, rales, use of accessory muscles, and/or nasal flaring1. Respiratory syncytial virus (RSV) acute bronchiolitis (AB) is the most common cause of infant hospitalization2,3.
The global RSV-acute lower respiratory infection (ALRI) hospitalization estimate, reported per 1000 children per year (95% confidence interval [CI]), was 19.19 (15.04– 24.48) among children <1 year of age4. Globally in 2015, an estimated 33.1 million (uncertainty range [UR] 21.6–50.3) episodes of RSV-ALRI resulted in approximately 3.2 million (2.7–3.8) hospital admissions and 59,600 (48,000–74,500) in-hospital deaths in children younger than 5 years. In children younger than 6 months, 1.4 million (UR 1.2–1.7) hospital admissions, and 27,300 (UR 20,700–36,200) in-hospital deaths were due to RSV-ALRI5. Endotracheal intubation (ETI) is required in approximately 24% of patients admitted to the pediatric intensive care unit (PICU)6.
There are many risk factors for RSV infection and bronchiolitis: age younger than 6 months7, older siblings8,9, lung disease10,11, congenital heart disease12, born before 35 weeks’ gestation13, and exposure to second-hand smoke14,15. However, risk factors for severe acute bronchiolitis (SAB) in previously healthy infants are not well known.
The main objective of this study was to investigate the effect of tobacco smoke exposure among severely PICU patients.