Abstract
Introduction
Progression of respiratory failure in ALS requires a closer follow-up process to determine the timing of application of NIV. Nocturnal hypoventilation (NH) generally precedes daytime hypercapnia.
Aim
To test telehome monitoring (THM) of NPO to detect early NH.
Methods
ALS patients without daytime hypoxemia and FVC > 80% pred received a THM device which acquires signals from an internal pulse oximeter and connects to modem by bluetooth technology. In a Web-page, oxygen saturation percentages calculated and displayed on a graphical user interface is accessed.
Mean time spent with a saturation below 90% (TB90%) for ≥5% of night time was calculated on 5 consecutive monitorings per patients. Measurements were repeated every 6 months over 2 yrs follow-up.
Results
14 ALS patients were studied. Mean TB90 ≥5% was detected in 5 subjects (35%) out of 14 when FVC was ≥70%pred and in the remaining 9 patients when FVC was between 69-55% pred. Arterial hypercapnia (PaC02 >45 mmHg) was detected only in 1 patient with FVC>60% pred. Patients started NIV when early NH was detected; nocturnal NIV was well tolerated and no patient developed acute hypercapnic crises over 2 year follow-up.
Conclusions
THM of NPO in ALS was more sensitive than usual FVC or daytime arterial blood gases in detecting early NH; 5 consecutive nocturnal monitorings reduced the intraindividual variability of the test.
If early detection of NH determines the timing of application of nocturnal NIV, the frequency of acute hypercapnic crises provoking hospital admission may be reduced.
Supported by Fondazione Cassa di Risparmio di Carrara.
- © 2014 ERS