When operating on Nadia, Karev tells Mer that Nadia has a mother because only a mother would take the time to do a dutch braid. A dutch braid is harder to do than a french braid. But looking back at the braid you see both, Nadia and her mother, have a french braid not a dutch braid.
Meredith called 911 for Ellis' suicide attempt in 1983. But per web "The Washington State Enhanced 9-1-1 (E911) Program came about as a result of passage of a 1991 voter referendum directing enhanced 911 emergency communications systems to be available statewide by Dec. 31, 1998. The referendum provided for a state E911 coordination office. This office would facilitate local planning and installation of such systems."
Meredith calls 911 for Ellis's suicide attempt in 1983 but Washington State did not widely use the 911 system until 1998.
When the paramedics are at the back of the ambulance, the strobing emergency lights are clearly LED technology, which did not exist at the time the action took place; it would be more than 20y before those became available.