Growing "case comments" field?

Good day,

I’d like to implement a *comment *field for all my patient cases.
The idea is that any form which updates information for a patient case has
a *comment *field at the end. This *comment *field should be appended (or
pre-pended) to the existing *comment *field on the case.

An example of how this would look:

··· ------------
  1. On case creation form, comment: “Patient has high BP, should be
    monitored”

    #case/comment =
    “1 Mar 2017: Patient has high BP 145/90, should be monitored (chw1
    )”

  2. On a follow-up form, comment: “BP improved slightly 140/85, keep
    monitoring.”

    #case/comment =
    “1 Mar 2017: Patient has high BP 145/90, should be monitored (chw1
    )”
    “10 Mar 2017 BP improved slightly 140/85, keep monitoring. (chw2)”

  3. On a follow-up form, comment: “Patient not at home today, could not take
    BP”

    #case/comment =
    “1 Mar 2017: Patient has high BP 145/90, should be monitored
    (chw1)”
    “10 Mar 2017: BP improved slightly 140/85, keep monitoring. (chw2)”
    “14 Mar 2017: Patient not at home today, could not take
    BP (chw1)”


Questions:

  1. Is this possible? Can I just load current value of #case/comment from
    the patient case and use *concat() *to create a new value to update it?

  2. Is there a limit to the length of the text field (e.g. 255 chars) that I
    will run into?

  3. Do you have a better suggestion for how I could implement this
    functionality?

Thanks!
Andrew