Measuring vital capacity in amyotrophic lateral sclerosis: Effects of interfaces and reproducibility.
Respir Med
; 176: 106277, 2021 01.
Article
in En
| MEDLINE
| ID: mdl-33310203
ABSTRACT
BACKGROUND:
Deterioration of vital capacity (VC) in amyotrophic lateral sclerosis (ALS) signifies disease progression and indicates need for non-invasive ventilation. Weak facial muscles consequent to ALS, with resulting poor mouth seal, may interfere with the accuracy of VC measurements.OBJECTIVES:
To determine whether different interfaces affect VC measurements in ALS patients and whether the interface yielding the largest VC produces an even higher VC when re-measured after one week (learning effect). To explore the relationship between optimal interface VC and sniff nasal pressure (SNIP), a measurement of global inspiratory muscle strength.METHODS:
Thirty-five patients (17 bulbar and 18 spinal ALS) were studied. Three interfaces (rigid-cylindrical, flanged, oronasal mask) were tested. One week after the first visit, VC was recorded using the optimal interface. SNIP recordings were also obtained.RESULTS:
In the bulbar ALS group, median (interquartile range) VC with the flanged mouthpiece was 8.4% (3.9-15.5) larger than with the cylindrical mouthpiece (p < 0.001). VC values with oronasal mask were intermediate to VC with the other two interfaces. In spinal ALS, flanged mouthpiece VC was 4.6% (2.3-7.5) larger than with oronasal mask (p < 0.0006). The latter was 4.5% (0.6-5.2) smaller than with the cylindrical mouthpiece (p = 0.002). In both groups, VC during the second visit was greater than during the first visit (p < 0.025). SNIPs were logarithmically related to VC values recorded with the flanged mouthpiece.CONCLUSION:
A flanged mouthpiece yields the largest values of VC in patients with bulbar and spinal ALS.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Respiratory Function Tests
/
Vital Capacity
/
Amyotrophic Lateral Sclerosis
Type of study:
Diagnostic_studies
Limits:
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Respir Med
Year:
2021
Document type:
Article
Affiliation country:
Italy