The Ambulance Beavers are characters of a running gag throughout Rocko's Modern Life. They are two beaver paramedics who appear whenever a character is seriously injured. However, instead of taking the character who is hurt off on a stretcher, they take the inaminate object the character was injured on. An example is when Rocko crashes his bumper car at the carnival in "Carnival Knowledge" and the Ambulance Beavers take away the car instead of Rocko.
When Rocko's appendix was hurting him in "Tickled Pinky," he fell off his jackhammer and they took the jackhammer away instead of Rocko. In the same episode, they took Heffer, after they were told to (and they actually got it right that time), for emergency hippo-suction (liposuction) after he rushed to the hospital with Rocko in tow. Their catchphrase is saying "Hup!" repeatedly, while carrying a stretcher, loading the object on, and driving off to the hospital. When they carried Heffer, they said "Hup" slowly, since Heffer was heavy.