Early Use of Noninvasive Mechanical Ventilation in Patients with Acute Hypercapnic Respiratory Failure in a Respiratory Ward: A Prospective Study

Abstract

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 dishcarge 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, PaCO 2 and PaO 2/FiO 2 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 succesfully 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.