Method for Single Intravenous Anesthetic Infusion in a Rodent Model

Shawn K Puri,Jing Li,Pratap R. Nadavaluru,Johan Reyes,Alex Bekker,Ming Xiong,Jiang Hong Ye

doi:10.4236/ojanes.2015.55019

Abstract

Venous catheterization, endotracheal intubation, and mechanical ventilation are necessary for performing total intravenous general anesthesia in rats. Intubation and IV cannulation of the rat is challenging because of the animals’ small size and the lack of equipment specifically designed for the restricted anatomical dimensions. Here, we present methods for tail venous catheterization and intubation that are quickly learned by the provider with clinical operating room experience but lack experience in the lab. For tail venous catheterization, each rat (n = 20) was gently restrained in a rat chamber; its tail was placed in warm water for 10 minutes, and a 24 gauge intravenous catheter was inserted into the lateral tail vein. The catheter was fixed in place using tape and attached to a T-connector for drug administration. A bolus of propofol (n = 10), ketamine (n = 7), or etomidate (n = 3) was administered to achieve rapid deep anesthesia. Once anesthetized, rats were intubated with the aid of a modified pediatric laryngoscope. The standard miller blade 0 was cut on each side for approximately 2/3 of the total blade length to remove a total of half the width. After the ventilator was properly set, the rats’ vital signs and metabolic status were monitored. Throughout the one-hour infusion, the rats’ physiologic parameters were maintained within normal range. These results indicate that intravenous general anesthesia can be performed effectively and safely in small animals using the refined catheterization and intubation methods tested in this study. These techniques are easily reproducible and learned as they mimic the tools and strategies commonly used in the OR.

Highlights

Intravenous (IV) administration of anesthetic drugs is a well-established practice in anesthetic delivery and a popular alternative to inhalational anesthesia [1]
Catheterization allows for drug administration, while intubation allows for steady-state conditions during in vivo experiments
The duration of anesthesia induced by the anesthetic bolus lasted approximately 10 minutes, a sufficient amount of time for the experimenter to fix the rat to the intubation stand and conduct intubation

Summary

Introduction

Intravenous (IV) administration of anesthetic drugs is a well-established practice in anesthetic delivery and a popular alternative to inhalational anesthesia [1]. Animal models such as the rat are extremely useful to further understand the safety and efficacy of intravenous anesthetic drugs. Catheterization allows for drug administration, while intubation allows for steady-state conditions during in vivo experiments. Performing these procedures on rats is challenging because of the animals’ small size. Many methods have been described with high rates of success, many of these are not learned by the novice practitioner. We describe in our paper a method, by mimicking equipment commonly used in the OR, that can be quickly learned and replicated by a novice laboratory provider

Methods

Results

Conclusion