This site may be of some help to you. http://patienteducation.upmc.com/Pdf/Esophagectomy.pdf
It is from the University of Pittsburgh and they have a good reputation. My surgeon studied there last year to learn the new non-invasive EC surgery technique.
I think you will find that the trial and error method is how you will know what he will tolerate. In the beginning, take it real slow. Things get better with time. Best wishes.