[Early use of noninvasive mechanical ventilation in patients with acute hypercapnic respiratory failure in a respiratory ward: a prospective study]. / Uso precoz de la ventilación mecánica no invasiva en pacientes con insuficiencia respiratoria hipercápnica aguda ingresados en una sala de neumología: estudio prospectivo.

BACKGROUND: In recent years, the optimal location for noninvasive mechanical ventilation (NIMV) has been a matter of debate. Our aim was to detect the effectiveness of NIMV in acute hypercapnic respiratory failure (AHRF) in respiratory ward and factors associated with failure. METHODS: 69 patients treated with NIMV in respiratory ward were prospectively evaluated. The success of NIMV was defined as absence of need for intensive care unit (ICU) transfer with patient's discharge from hospital (group 1), failure of NIMV was defined as need for ICU transfer (group 2). RESULTS: The mean age was significantly higher in group 2. The cause of respiratory failure was COPD in 51 patients, obesity-hypoventilation syndrome in 14 and kyphoscoliosis in 4 patients. NIMV was successful in 55 patients and unsuccessful in 14. There was no significant difference between the two groups for pretreatment pH, PaCO2 and PaO2/FiO2. After 1h and 3h of NIMV there was significant improvement in group 1. After 3h of NIMV, in group 1 respiratory rate was significantly decreased. The pretreatment APACHE II score, respiratory rate, frequency of pneumoniae, associated complication and comorbid disease was significantly higher in group 2. The success rate was higher in patients with good compliance to NIMV. CONCLUSION: NIMV can be successfully applied in patients with AHRF in respiratory ward. The associated factors with NIMV failure are absence of early improvement in blood gases and respiratory rate, bad compliance to NIMV, older age, presence of associated complication, comorbid disease, pneumonia and high baseline respiratory rate.