Abstract

Background:
Intranasal lidocaine administration is a common treatment used to facilitate the passing of endoscopes and nasogastric tubes in horses. However, no research has supported its use in equine practice.

Aim:
To compare patient reactivity and endoscope passage time between intranasal lidocaine and intranasal saline prior to gastroscopy.

Methods:
This blinded, randomized clinical trial included 25 horses presenting for gastroscopy. Following the administration of sedation and prior to gastroscopy, 10mL of saline (CON) was administered intranasally to 12 horses in the control group or 10mL of 2% lidocaine (LID) was administered intranasally to 13 horses in the lidocaine group. The recorded data included signalment, location of scoping (field or hospital), sedation, grade of reactivity on a 6-point scale (0 for no reactivity up to 5 when the scope could not be passed), and time to passage from the nares to the cardia.

Results:
The time to reach the cardia in the CON group was 73 (35 - 183) seconds and the time to reach the cardia in the LID group was 70 (45 - 210) seconds (p= 0.8). The number of horses with a reactivity grade less than or equal to 1 in the CON group was 75% (9/12) compared with 69% (9/13) in the LID group (p= 0.12).

Conclusion:
This small study did not identify any significant benefit from administering intranasal lidocaine prior to endoscope passage.

Key words: Nasogastric, Endoscopy, Nasal passage