Abstract

An 8-year-old male bottlenose dolphin (Tursiops truncatus) was diagnosed with Aspergillus fumigatus pneumonia, and treated with voriconazole therapy.^1-4 Subsequent CT and bronchoscopy revealed resolved pneumonia, with the exception of persistent disease in the caudal portion of the right lung, distal to two regions of stenosis within the right primary bronchus (lobar branches 5 and 7), which prompted consultation with interventional pulmonologists.^5-8

A therapeutic bronchoscopy was performed under intravenous sedation. An electrosurgery needle knife was used to make radial incisions, followed by balloon bronchoplasty to re-open the lumen.⁹ Distally, the second stenosis had become completely occluded. Due to risks of vascular injury with blind dilatation, management was deferred. Post-operative CT showed resolution of the proximal stenosis, but distal bronchial occlusion and post-obstructive pneumonia.

A second therapeutic bronchoscopy was performed under general anesthesia using apneustic anesthesia ventilation (AAV) with mixed medical air and oxygen supplementation due to CO₂ laser use.¹⁰ During the procedure, an endoscopic needle was utilized to puncture the occlusion, followed by insertion of a cannula and guidewire through the stenosis. Diluted iohexol (Omnipaque) was injected through the cannula under fluoroscopic guidance to ensure proper cannulation of the airway.¹¹ Sequential balloons were then utilized for airway dilatation. While moderate stenosis remained, post-obstructive secretions were noted, consistent with successful opening of the airway.

Here we report the first use of airway electrosurgery and contrast bronchography-guided balloon dilation to manage an airway stenosis in a dolphin. To date, the animal remains clinically normal; repeat interventions to open the occluded segment may be performed, if needed.

Acknowledgements

The authors thank the veterinary technicians and training staff at the National Marine Mammal Foundation and U.S. Navy Marine Mammal Program for their excellent care and assistance with this case, as well as John Downs, David Hodgson, Alex Bukoski, Neil Euliano, Paul Blanch, and Mark Baird for their support and expertise. Special thanks to Matt Willis from Karl Storz Endoscopy for providing endoscopes; and Pacific American for their fluoroscopy assistance.

*Presenting author

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