A novel inhaled anesthesia technique for concurrent direct laryngoscopy in rats

Abstract

The current anesthetic standard for laryngoscopy in rats utilizes injectable intraperitoneal anesthesia. Injectable anesthesia is suboptimal for short procedures due to variability in anesthesia duration and anesthetic side effects. Conversely, inhalational gas anesthesia offers precise titration with a rapid onset and offset. However, its use during laryngoscopy has not been documented due to existing administration techniques obstructing direct visualization of the larynx. The technique described here allows real-time visualization of the rat larynx with concurrent administration of inhaled anesthetic gas. This method is particularly well-suited for recurrent laryngeal nerve or vocal fold pathology studies, where repeat visualization of the larynx is necessary.

Keywords

anesthesia / endotracheal intubation / laryngoscopy / rodents / vocal cords

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RIGHTS & PERMISSIONS

2025 The Author(s). Animal Models and Experimental Medicine published by John Wiley & Sons Australia, Ltd on behalf of The Chinese Association for Laboratory Animal Sciences.