I contract states that I will give clients 60 days notice of intent to close for my 'vacation' which I take 10 days of over the course of the year and as much notice as possible if I need to take 'family emergency/sick' time where I take at least 10 days over the course of the year ... so my clients know going into our relationship that they need to have at least 4 weeks of back up care coverage each year in addition to closures for stat holidays and Christmas break.

I also agree with Gramma I would not count this as my 'vacation' unless you cannot afford to take the additional time off later because well IMO vacation is time meant to be spent 'decompressing' and well caring for a spouse recovering from surgery is anything but a 'vacation' I empathize because I went through a period of bad health between 2000 and 2005 where each year my vacation time was spent each year recovering from a surgery of some sort because I could not afford to take off additional time off work unpaid and it really burnt me out!

If it was possible I might see if they could arrange his surgery for a Thursday and than hopefully the Thursday, Friday and weekend is enough time to 'recover' so you are only closed for the 2 days ... if it is not 'emergency' surgery where he must have it done next week type thing they are actually pretty good about working around things if you are self employed or do not get paid sick time.