Passive Versus Active Circuit During Invasive Mechanical Ventilation in Subjects With Amyotrophic Lateral Sclerosis.

BACKGROUND: Until recently, it has been considered essential to maintain the use of a double-limb circuit in patients with amyotrophic lateral sclerosis (ALS) to avoid rebreathing expired air during invasive mechanical ventilation. Currently, life-sustaining home ventilators can work with a single, lighter circuit that is easier to manage. Our aim was to evaluate the effectiveness and safety of a single-limb circuit with intentional leaks (passive circuit) in comparison with a circuit with an expiratory valve (active circuit), in subjects with ALS who use invasive home ventilation. METHODS: We conducted a retrospective single-center study. The enrolled subjects were divided into 2 groups according to the type of exhalation port. The aim of the study was to compare arterial blood gases; nocturnal oxygen saturation recordings; and the occurrence of adverse events, both clinical and technical events. In addition, we compared the rate of mortality and unplanned hospital admissions that occurred within a year after discharge from the hospital. RESULTS: Forty-three subjects were included in our study: 23 who used a passive circuit and 20 who used an active circuit. No significant difference in nocturnal and diurnal gas exchanges was detected. The incidence of adverse events was significantly higher in the active circuit group (85% in active circuit vs 30% in passive circuit, P < .001). However, by splitting the adverse events into 2 categories, clinical and technical, the technical events were significantly more frequent in the active circuit group. None of these events led to hospital admission or death. CONCLUSIONS: The passive circuit was shown to be as effective and safe as the active circuit during home invasive ventilation in the subjects with amyotrophic lateral sclerosis. A future randomized controlled study is necessary to confirm these results and to extend indications to other pathologies.

The Myotonic Dystrophy Health Index: Italian validation of a disease-specific outcome measure.

The Myotonic Dystrophy Health Index (MDHI) is a disease-specific, self-reported outcome measure that assesses total disease burden and 17 areas of Myotonic Dystrophy type 1 (DM1) specific health. This study translated the MDHI into Italian and validated the instrument using a cohort of Italian DM1 patients. Italian DM1 patients were interviewed regarding the form and content of the instrument. Thirty-eight DM1 patients were subsequently recruited to test the reliability and concurrent validity of the instrument by serially completing the MDHI and a battery of clinical tests. Lastly, we determined the internal consistency of the Italian MDHI and each of its subscales. The internal consistency was excellent in the total Italian MDHI score and acceptable in all of its subscales; the test-retest reliability was high (intraclass correlation coefficient = 0.95); Italian MDHI total scores and subscales were associated with neuromuscular function, cognitive and social health, respiratory function, and quality of life. Overall, the Italian MDHI is valid and well suited to measure the multi-dimensional aspects of disease burden in Myotonic Dystrophy clinical trials.