We received a patient in respiratory distress with a non-rebreather mask to the patient's "new" trach. The pt needed to be on the vent, but the un-cuffed-trach had to be switched out to a cuffed-trach first. That was done and the patient improved dramatically. Unfortunately, at shift change while turning the patient, the cuffed-trach slid out slightly. When reinserted, it forced air into the interstitial spaces, which caused the patient's neck and face to blow up. The patient rapidly de-sated and went pulseless. The charge RN tried to bag the patient through the ETT and cuffed-trach, but that did not resolve the problem. I wish I had read this forum beforehand, because not one of us (even those with 30 years of experience) knew or thought to immediately bag the patient's mouth. I also think the immediate change in the patient's facial appearance was shocking and somewhat horrifying, which created a lot of panic. Thankfully, the MD arrived quickly and intubated the patient and the patient survived. When we debriefed after the code, we all learned a valuable lesson. I'm just thankful this patient survived.