Functional magnetic stimulation of the respiratory muscles in dogs

✍ Scribed by Vernon W. Lin; Jaroslaw R. Romaniuk; Anthony F. DiMarco

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 290 KB
• Volume: 21
• Category: Article
• ISSN: 0148-639X
• DOI: 10.1002/(sici)1097-4598(199808)21:8<1048::aid-mus9>3.0.co;2-8

✦ Synopsis

This study assessed the ability of functional magnetic stimulation (FMS) to activate the respiratory muscles in dogs. With the animal supine, FMS of the phrenic nerves using a high-speed magnetic stimulator was performed by placing a round magnetic coil (MC) at the carotid triangle. Following hyperventilation-induced apnea, changes in volume (⌬V) and airway pressure (⌬P) against an occluded airway were determined. FMS of the phrenic nerves produced substantial inspired function (⌬V = 373 ± 20.5 mL and ⌬P = -20 ± 2.0 cm H 2 O). After bilateral phrenectomies, maximal inspired ⌬V (219 ± 12.2 mL) and ⌬P (-10 ± 1.0 cm H 2 O) were produced when the MC was placed near the C6-C7 spinous processes, while maximal expired ⌬V (-199 ± 22.5 mL) and ⌬P (11 ± 2.3 cm H 2 O) were produced following stimulation near the T9-T10 spinous processes. We conclude: (1) FMS of either the phrenic or upper intercostal nerves results in inspired volume production; (2) FMS of the lower intercostal nerves generates expired volume production; and (3) FMS of the respiratory muscles may be a useful noninvasive tool for artificial ventilation and assisted cough in patients with spinal cord injuries or other neurological disorders.