Objective. To determine the epidemiology and therapeutic management of patients with severe acute bronchiolitis (AB) admitted to paediatric intensive care units (PICUs) in Spain. Design. Descriptive, prospective, multicentre study. Setting. Sixteen Spanish PICUs. Patients. Patients with severe AB who required admission to any of the participating PICUs over 1 year. Interventions. Both epidemiological variables and medical treatment received were recorded. Results. A total of 262 patients were recruited; 143 were male (54.6%), with median age of 1 month (0-23). Median stay in the PICU was 7 days (1-46). Sixty patients (23%) received no nebuliser treatment, while the rest received a combination of inhalation therapies. One-quarter of patients (24.8%) received corticosteroids and 56.5% antibiotic therapy. High-flow oxygen therapy was used in 14.3% and noninvasive ventilation (NIV) was used in 75.6%. Endotracheal intubation was required in 24.4% of patients. Younger age, antibiotic therapy, and invasive mechanical ventilation (IMV) were risk factors that significantly increased the stay in the PICU. Conclusions. Spanish PICUs continue to routinely use nebulised bronchodilator treatment and corticosteroid therapy. Despite NIV being widely used in this condition, intubation was required in one-quarter of cases. Younger age, antibiotic therapy, and IMV were associated with a longer stay in the PICU.