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Effect of posture on the flow-volume loop in two patients with euthyroid goiter
M Meysman1, M Noppen, W Vincken
1Respiratory Division, Academic Hospital, University of Brussels, Belgium.
Chest
|December 1, 1996
Summary
Flow-volume loops (FVLs) can diagnose upper airway obstruction in patients with goiter. Comparing FVLs in different body positions helps identify posture-related respiratory symptoms.
Area of Science:
- Pulmonology
- Otolaryngology
- Medical Diagnostics
Background:
- Respiratory symptoms, particularly those related to posture, can be challenging to diagnose.
- Goiters can cause extrinsic compression of the upper airway, leading to variable symptoms.
Observation:
- Two patients with goiters experienced respiratory symptoms exclusively when lying down.
- Flow-volume loops (FVLs) were recorded in sitting, supine, and lateral decubitus positions.
Findings:
- Recumbent postures revealed upper airway flow limitation, evidenced by altered flow rates, obstruction indices, and FVL morphology compared to upright posture.
- Postural changes in FVLs resolved after thyroid surgery in one patient.
Implications:
- Comparing FVLs across different body positions is a valuable tool for diagnosing extrinsic upper airway masses, such as goiters.
- This method aids in clarifying the cause of posture-related respiratory symptoms, improving diagnostic accuracy.
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