Experience Using a New Gastric Tube Tip Localization System (Tumguide)
This case report describes use of a new gastric tube tip localization system, the Tumguide (Otsuka Pharmaceutical Factory), in a 50-year-old male patient undergoing general anesthesia for treatment of a mandibular fracture. After induction of general anesthesia and intubation, a gastric tube was inserted using the Tumguide system. After the gastric tube was advanced approximately 50 cm, light from the Tumguide was confirmed emanating below the left rib. The gastric tube was ultimately advanced another 20 cm and fixed in place. A postoperative chest radiograph confirmed the gastric tube was positioned inside the stomach; however, it was withdrawn approximately 10 cm and resecured. Although there are various methods, like radiography, for confirming appropriate positioning of a gastric tube, the insertion process is blind. The Tumguide uses light with high biopermeability for illumination, which enables the gastric tube tip to be indirectly viewed as it is moved into position. Although this system has not gained wide usage, we feel this is a useful device that merits further exploration.

The Tumguide Device
The Tumguide consists of a light source device and a thin fiberoptic cable.

Light Source Connection and Stopper
The fiberoptic cable connects to the light source device and the cable tip emits light when the button is pressed. The stopper (yellow arrow) fixes the positioning of the cable relative to the gastric tube.

Luminescence in the Abdomen
The gastric tube has been successfully advanced into the stomach if light is observed emitting from the abdomen.
Contributor Notes