How to pass parameters from a .net application to SSRS

This is the first time I've tried to load a SSRS report from a .net application.  I would be using Response.Redirect.  Below what I have as the link.  So far it loads the SSRS report but the parameter part of it is not working.  Looked and looked for an answer and found a bunch of different possibilities, but none have worked so far.

Here's my .net statement:

Response.Redirect(http://reports/Reports/Pages/Report.aspx?ItemPath=%2fDave+Test%2fPhysician+Scheduling%2fSVMGPTO&rs:Command=Render&P1=rptYR&p2=DrInit)

I'm trying to pass the report year (rptYR) and doctor initials (DrInit) to my SVMGPTO SSRS report.  Any help would be much appreciated.

Thanks!