In Tokyo, the emergency room is staffed with enough people that everyone has multiple attendants always taking care of them, whereas in the US it can often be hours between check-ins by the staff.
In an American emergency room, it is up to the patient to undress themselves and put on a gown; if they are unable to do that, the staff will cut the clothing off. In Japan, they do as much as possible without removing any clothing, and are exceptionally conscientious about the patient's comfort.
In a Japanese emergency room, the language barrier is something they attempt to overcome and make sure that everyone knows the same amount of information; in an American emergency room, the attending staff tends to not communicate or even listen to the patient.
In an American emergency room, regardless of what's going on they always hook you up to a saline drip, while in a Japanese emergency room, that is considered a treatment that they only perform when it appears to be necessary.
In an American emergency room, if you have to use the bathroom it takes quite a lot of time before an attending nurse even finds out that you need to, and they just give you a jar to pee in before disappearing. In a Japanese emergency room, they accompany you to the bathroom and make sure that you're doing okay.
An American emergency room bills you later, via the convoluted process of American medical insurance. A Japanese emergency room either bills your insurance directly and asks you to pay the difference (if you have insurance), or just bills you directly and has you pay before you leave (and provides receipts for reimbursement with foreign insurance claims later). Fortunately, the overall uninsured bill of a Japanese emergency room is less than the copayments involved in an American emergency room, so even if one doesn't get reimbursed you still end up ahead.
An American emergency room is doing good if they keep track of your name and mailing address. A Japanese emergency room issues you a personalized smart card that keeps track of your medical history with them for easy access later.
On the other hand, an American emergency room understands that people come in all sorts of sizes and shapes, whereas in a Japanese emergency room, the beds are very small and cramped, the slippers they give you for going to the bathroom (you don't wear shoes!) are tiny, and the adhesive on the tape sticks exceptionally well to a hirsute-American's arms.
Neither one can figure out what the hell is wrong with me.