Aahh, the evil beast!
The Sengstaken tube is an impressive contraption: it's about a meter long, ca 2 cm thick and is not very nice to swallow, but that's exactly what it's for: designed to save lives, the Sengstaken tube is a cousin of the gastroscope, but without the fiberglass optics. Its sole purpose is to be pushed down the oesophagus by a skilled physician and then to put pressure on bleeding oesaphageal varices (inflated veins lying under the lining of the gullet due to the blood looking for a different way back to the heart in the case of Liver cirrhosis) via a balloon that the physician can inflate. After securing the tube with a second, smaller balloon below the entrance to the stomach, the patient keeps this cobra-sized monster in his gullet, fed and watered via a third lumen, giving access to the victim's stomach.
Oesophageal varices are a lifethreatening complication of liver cirrhosis, and if the patient's gastroenterologist isn't able to control the bleeding with a normal gastroscope, the Sengstaken tube is the next best option to save the life of the patient, as without quick intervention he's going to bleed to death, as his unusable liver is not able to produce enough bloodclotting proteins to suppress the bleeding.
So, do you really want another beer?