The sequence was shot by turning the entire room upside-down on a gyro set and sending the blood down through the bed.
Heather Langenkamp and
Robert Englund, in costume, were on hand to watch the filming. The room itself was to be turned as the blood flowed, but it was turned in the wrong direction, and blood began to squirt prematurely. A door to the room opened, and the fake blood gushed onto exposed wires, creating a real hazard for the crew. Fortunately, Englund pulled Langenkamp away to safety before anything serious would have happened, and the sequence was somehow salvaged. This incident is described by Englund in a booklet in the commemorative boxed set.
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