As a professional French-English interpreter, here is my two cents’ worth. ALL of the above suggestions are good. And yes, French people say “Tu me manqueras” or “Vous me manquerez”. Literally, it means “You, to me, shall be lacking”.
The English formulation “I miss you” sounds funny to French people. It sounds like you were shooting at them and are sorry that the bullets went astray!
You use the “tu” form if the person is much younger or a very close friend. You use the “vous” form adressing someone older or in a position of authority over you, or a stranger. (Or if you are speaking to more than one person, but that doesn’t apply here.
In this case, you will have to decide if this person is a “tu” or a “vous”.
But don’t worry, they will NOT be horribly offended if you use one or the other. The two forms are easily interchanged.
The one pitfall is prononciation. Most people do not realize that while French and English use the same alphabet. combinations of letters do not create the same sounds. “OI” would be pronounced “oy” as in “coitus” in English, but is pronounced “wah” as in “Benoit” in French.
So here is the sentence you need, with a pronouncing guide.
Vous irez chez vous demain. Bonne chance. Vous me manquerez beaucoup.
Vooz-eerai chay voo duh-may(n). Bun chanse. Voo me mankeray bocoo.
(Note that the S at the end of the first “Vous” is pronounced because it comes before a word beginning with a vowel. Single S in French sounds like a Z.
Do not pronounce the n at the end of “demain”, but give a slight nasal sound to the last syllable, so that it comes out as if you were saying “demay” and your nose is stuffed up. Practice pinching your nose on the last syllable and you will get the hang of it. But don’t do it in front of the patient or they will think you are nuts! 
Bonne chance et dites-moi si vous avez réussi à parler à votre patient!
Learn something new every day!