Effects of left recurrent laryngeal neurectomy, prosthetic laryngoplasty, and subtotal arytenoidectomy on upper airway pressure during maximal exertion.

The study evaluates two surgical methods, prosthetic laryngoplasty and subtotal arytenoidectomy, in reversing increased upper airway pressure caused by left recurrent laryngeal neurectomy in horses. The results indicated prosthetic laryngoplasty was more effective.

Study Design and Methodology

• The researchers used a total of ten healthy horses for the study. These horses were subjected to maximal exercise for airway pressure measurement before and after a specific surgical procedure.
• The surgical procedure implemented was called left recurrent laryngeal neurectomy, which was performed to induce changes in the upper airway pressure of the horses. This procedure involves the surgical resection of the left recurrent laryngeal nerve and is known to increase upper airway pressure.
• Upper airway pressure was measured using a nasotracheal catheter system and a portable pressure transducer. These devices allowed for the accurate recording of the pressure levels in the horse’s upper airway both before and after surgery.
• After the laryngeal neurectomy, horses were divided into two groups. One group underwent prosthetic laryngoplasty, and the other group underwent subtotal arytenoidectomy, both 16 weeks post neurectomy.

Key Findings

• The results showed a significant increase in the upper airway pressure in the horses during maximal exertion after the left recurrent laryngeal neurectomy.
• However, this increase in pressure was effectively reversed through the implementation of prosthetic laryngoplasty. The horses in this group exhibited lower upper airway pressures during maximal exertion after receiving the surgery.
• Subtotal arytenoidectomy, on the other hand, was less effective at reversing the increased upper airway pressure caused by the laryngeal neurectomy.

Conclusion

• The study concluded that prosthetic laryngoplasty was more effective than subtotal arytenoidectomy in reversing upper airway pressure increases in horses following left recurrent laryngeal neurectomy.
• This suggests that prosthetic laryngoplasty may be a more suitable surgical interventional strategy for mitigating adverse effects of left recurrent laryngeal neurectomy in horses.