Parsing HTTP Response

I am struggling with parsing the HTTP response.  I thought fv!result in the rule that called the integration would allow me to access the body of the response.  However, I am getting errors.  The three values I am trying to access are highlighted below.  Screenshots of the function where I call the integration and the response from the call are shown below.  I would like the three values stored in local variables so I can display the text messages to the user.  Thank you in advance!

                         rule!CreatePatientResource(
                           givenName:local!firstName,
                           familyName:local!surName,
                           gender:local!gender,
                           dateOfBirth: local!dateOfBirth,
                           onSuccess:
                           {
                             a!save(local!registrationErrorMessage,null),
                             a!save(local!registrationComplete,true()),                 
                             a!save(local!registrationConfirmationMessage, 
                               concat(tostring(local!firstName), " ",tostring(local!surName)," was successfully registered"))

                           },
                           onError: {
                              /*Handle HTTP error */
                             a!save(local!registrationErrorMessage, fv!error.message)
                           }
                         )