Elimination of abnormal respiratory noise in horses (Proceedings)

Aug 01, 2008

Sources of respiratory noise

• Laryngeal hemiplegia

• Dorsal displacement of the soft palate

• Pharyngeal collapse

• Alar fold flutter

• Epiglottic entrapment

• Axial deviation of aryepiglottic folds

• Lower airway inflammatory disease?

Sources of noise associated with inhalation

• Laryngeal hemiplegia

• Axial deviation of aryepiglottic folds

• Pharyngeal collapse

• Lower-airway inflammatory disease

• Epiglottic retroversion

• Alar fold flutter/collapse

Sources of noise associated with exhalation

• Dorsal displacement of the soft palate

• Alar fold flutter/collapse

• Epiglottic entrapment

• Lower-airway inflammatory disease?

Diagnosis of respiratory noise

• Can be a challenge!

• Not all pathologies have consistent noise production

o DDSP did not always produce an abnormal respiratory noise experimentally (Derksen et al AJVR 200l;(62) 659-664)

• Not all noises indicate pathology

• Resting endoscopy

• Treadmill endoscopy

• Sound analysis

o Treadmill

o Field

Sound analysis

• Acquisition of respiratory sounds

• Can be performed in the field or on treadmill with specialized microphone apparatus and recording device

• Recordings digitized and analyzed using computer-based spectrum analysis

• What sound recordings have been studied?

o Normal horse

o LLH-affected horse

o Dorsal displacement of soft palate

o Other pathologies?

o Alar fold flutter/collapse

• Both inhalatory and exhalatory with sharp spikes Cable et al AJVR 2002;(63)1707-13

o No other pathologies extensively studied

• Not easily reproduced experimentally

• Clinical prospectives necessary

Treatment for abnormal respiratory noise

• Identify source 1st!

• Source will dictate treatment

• Axial deviation of the aryepiglottic folds

o 52 racehorses with ADAF

• 83% had noise

• Laser resection had a more significant affect on noise reduction and return to racing

• Rest and anti-inflammatory therapy less effective

• Alar fold flutter/collapse

o Sound analysis moderate sensitivity and specificity in experimental alar fold collapse (Cable CS et al 2002 Dec;63(12):1707-13)

o In 22 race horses

• Manual elevation decreased noise in 11/11

• Clips or mattress sutures decrease noise in 8/8