DIY Video Laryngoscopy in Rats–Safe, Fast and Reliable

Abstract

IntroductionThe airway management of rats in the field of basic research is of great importance. Intubation is needed for general anesthesia, ventilation, and the use of neuromuscular blocking agents. For survival studies, especially, a less invasive intubation technique is preferred over tracheostomy. In the past, several different methods with high success rates have been described, but most need a high level of technical effort, training, and financial expenditure. In humans, video laryngoscopy for intubation is the most successful technique; it may also be feasible in rats with simple and cost‐effective devices.HypothesisBy using a commercial flexible video endoscope (VE), with small modifications for direct visualization, and the Seldinger‐Technique, intubation in rats can be quick, easy and reliable.MethodsA cost‐effective and waterproof VE (GiraffeCam, 5.5 mm diameter) with USB‐connection and an integrated light source was purchased. Due to its softness, and for fixation on the board, a 20 cm wire attached with surgical tape was added to the VE for more rigidity. After anesthesia was induced with an intraperitoneal injection of pentobarbital (45mg/kg), each rat was placed on its back on the board and fixed in position with surgical tape. The board was then secured in place on the bench at a 45° angle head up. The VE was hooked up to the board and connected to a computer. The tip of the VE was gently introduced into the mouth, on one side of the upper incisors, until the vocal cords could be identified on the video screen. A 14‐gauge catheter, used as endotracheal tube (ET), was prepared with a stylet (15 cm PE50 tubing) that was inserted and advanced 1 cm past the catheter tip. The ET was inserted into the trachea, and once past the vocal cords, the stylet was pulled back. One hundred (100) rats (30 Zucker Diabetic Fatty, 70 Sprague Dawley; weight between 350–450g) were intubated by this technique and used for experiments with cardiac arrest and resuscitation.ResultsAll intubation attempts were successful on the first attempt, with a proper placement of the ET. No complications, such as bleeding occurred, and all rats were ventilated without problems. Furthermore, this technique can be performed with little previous experience and in less than one minute.ConclusionWith estimated costs of approximately $30, this VL intubation procedure is a safe, fast and reliable technique for rat intubation.Support or Funding InformationDr. Balzer is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Project number 397561247. Additional support provided by institutional funds, NIH grant (5R01 HL123227), and a Merit Review Award (I01 BX003482) from the U.S. Department of Veteran Affairs Biomedical Laboratory R&D Service awarded to Dr. Riess. image imageThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.