Prolonged and intensive monitoring after starting non-invasive ventilation improves tolerance in patients with amyotrophic lateral sclerosis

Background: The most frequent cause of death in patients with amyotrophic lateral sclerosis (ALS) is respiratory failure (RF) secondary to impairment of the respiratory musculature. In recent years, some studies have indicated that non invasive ventilation (NIV) improves survival and quality of life of ALS patients with RF. One restricting factor to the efficacy of NIV is bulbar involvement, but little is known about predictors of NIV adaptation and tolerance. Objective: To evaluate the effect of prolonged and intensive monitoring in a multidisciplinary ALS clinic setting on tolerance to NIV in ALS patients with RF. Patients and Methods: We prospectively monitored all consecutive ALS patients with RF who attended our ALS Center since June 2006. NIV was offered to 20 eligible patients (11 Mand 9 F) according to current guidelines and it was initiated during a hospital stay in our ALS Center. Nine patients presented with severe (n_5) or mild-moderate (n_4) bulbar impairment. During the whole hospitalization period, all patients underwent a respiratory kinesitherapy program. Patients were assessed by: i) pulmonary function; ii) disability; iii) nutritional status; iv) quality of life. After discharge, all patients were regularly followed-up at threemonths interval. According to accepted criteria, tolerance to NIV was defined as the ability to use the ventilator for more of 4 hours/day, for at least 60 consecutives days. NIV settings were adjusted as necessary during follow-up. Results: The mean interval time for adaptation to NIV was 592 days but the patients were allowed to prolong their hospital stay for an average extended period up to 3 weeks, during which a careful monitoring of NIV was performed. We observed that 19 of the 20 patients who initiated NIV, even those with severe bulbar impairment, remained tolerant at twelve months follow-up. One patient, with a moderate bulbar impairment, became non-tolerant to NIV three months after adaptation because of persistent airways mucus accumulation. Of the 19 tolerant patients, 11 (57.9%) had at least one change in NIV settings during the first year of follow-up. Conclusions: Our study show that an intensive and prolonged monitoring in a hospital setting after NIV adaptation increases tolerance, even in patients with severe bulbar impairment. Moreover, a respiratory kinesitherapy during the NIV training and the NIV settings adjustments appear to further increase the tolerance.