Help- need advice on time off work
FMLA is actually set in hours so you can take an hour here or there as necessary (intermittent). Unless you have chronically asked to take time off in the past for other reasons, I see no manager balking about a specific four week appt. need, especially since they understand the purpose. Is there a chance you can ask to flex and make up your time if you are worried about your workload?
Also recognize you'll be off work for awhile after surgery (usually 3-4 weeks) but there are appointments afterward too. FMLA is best to get in place now because it will cover the whole instance of health need.
I try to make up my time when I can by working a 1/2 hour of my lunch or come in early/stay late. That way I don't have to use my sick leave, vacation, or go without pay. By the way, I'm also a manager and have seen my fair share of people who use FMLA. It's a lot more settling to work with someone who is honest and direct about their time off needs. The ones who take the whole day off for one appointment (and I legally can't inquire too much) get to be wearing.
on another note...
Flex/make up time can be made up in the same week (at least at my work). In my case I have to travel an hour each way for my appointments so I try to hit two (MD and dietician) at the same time). My hours are 7-4 also and for these follow ups I schedule as early as possible and am in to work around noon. I do short lunches and longer days all week long to make up as much time as possible.