We have different codes. We have the usual code "blue", but we have a specific code "white" for those times a patient passes out, has a vagal, etc.
We have a specific team that responds, and there are enough people on it that we are typically fine.
If someone is on lunch they still come, and we sort out time cards after. We have "go bags" which contain pens, documentation paperwork, b/p cuff, stethoscopes, accuchecks, and biox machines.
We have people from all over respond. Maintenance responds in case they need to direct an ambulance, our "green shirt/greeters" respond with a wheelchair in case it is needed, even admin shows up in case more support is needed. It isn't always perfect, but we often have the staff we need to address the issues as they arise.