Maybe some don't, all of the ones I worked in did. For the most part our timing can go plus or minus 1 hour on medication administration in general and anything that specifically can't will be reflected in the MAR. It's mostly seamless. Many actions that are specific require peak and trough levels anyway so they're kind of self correcting and medications that need constant coverage are generally supplied by IV so we're living on the drip's time, not the clock.
In the end, the nurse themselves have to use their knowledge to manage it, but it's not bad.
Now thats got me thinking something rather grim but interesting. If a baby is born just before clocks go backwards, then due to some complication dies less than an hour later, just after they can gone back, would the baby have a time of death before its time of birth?