hi,
Try...
ALTER PROCEDURE SearchByMedi@MedicareNum nchar (10),@LastName varchar(50),@PatientID nchar(10) ASBEGIN
Select * from PatientWHERE (@MedicareNum=MedicareNum or @MedicareNum='' or @MedicareNum= NULL)AND (@LastName=LastName or @LastName='' or @LastName= NULL)AND (@PatientID=PatientID or @PatientID='' or @PatientID= NULL)
END
hope this will help you.