Related Experiment Video
Updated: Jul 13, 2026

Conducting Respiratory Oscillometry in an Outpatient Setting
Published on: April 8, 2022
Medialization of paralyzed vocal fold does not increase respiratory resistance measured by impulse oscillometry
Antti Saarinen1, Anssi R A Sovijärvi, Lauri Karhumäki
1Department of Respiratory Medicine, Central Finland Health Care District, Kinkomaa Hospital, 40930, Kinkomaa, Finland. antti.saarinen@ksshp.fi
Abstract:
Injection laryngoplasty restores voice in subjects with unilateral vocal fold paralysis, but knowledge of its effects on airflow dynamics is limited. Impulse oscillometry (IOS) is a non-invasive technique to investigate airway resistance. It is easily performed during normal breathing. A prospective study was conducted in order to investigate the effects of autologous fascia injection on airflow dynamics. IOS, flow-volume spirometry, acoustic analysis of voice, voice handicap index (VHI) questionnaire and subjective dyspnoea score were recorded before and 5-11 months after the operation. There was no significant change in respiratory resistance (Rres) or other variables of IOS. FEV1/FVC decreased from 0.80 to 0.77 (P = 0.02), but other variables of spirometry did not change significantly. Acoustic properties of voice (noise-to-harmonics ratio, shimmer, jitter, maximal phonation time) and VHI improved significantly. No change in dyspnoea occurred. In conclusion, medializing of a paralysed vocal fold improves voice, but does not have a clinically significant adverse effect on breathing. Flow-volume spirometry is more sensitive than IOS to changes in airflow dynamics after medialization.
Related Concept Videos
Respiratory System Abnormal Finding II: Palpation and Auscultation
Palpation Findings
During a respiratory assessment, palpation can reveal several vital abnormalities:
Physical Assessment of the Respiratory Tract II: Palpation
Thoracic Palpation
Thoracic palpation detects tenderness, masses, lesions, respiratory excursions, and vocal fremitus. The nurse assesses...
Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
Respiratory Volumes
Tidal Volume (TV) Tidal volume (TV) is the air inhaled or exhaled in a...
Mechanical Ventilation II: Invasive Ventilation
Negative-Pressure Ventilators
Negative-pressure ventilators create a vacuum around the chest or body to draw air into the lungs, simulating breathing. This method does not require an...
Atelectasis II: Pathophysiology

