Open file as another user, using node.js

I have a node.js program running as a service on my windows PC which I use to open files. The only way I have found to make this work is to use node.js to open PSExec, as node doesn't appear to have the ability to open a program as another user (in windows).

The code below works, however it is somewhat insecure, as the username and password can be discovered by watching process monitor, or even the command line column in task manager. I don't store the password in the source by the way, just put it there to keep the example simple.

var EventLogger = require('node-windows').EventLogger;
var log = new EventLogger('File Launcher starting');
var exec = require('child_process').exec;
var userName = "mike";
var password= "mikesPassword";
var fullPath= "C:\folder\file.xls";

exec("PSExec.exe -accepteula -h -d -u "+userName+" -p "+password+" -i 1 C:\\WINDOWS\\SYSTEM32\\CMD.EXE /c start \"\" \""+fullPath+"\"",{cwd: process.cwd}, function(error, stdout, stderror) {
if(error){
    log.error(stderror.replace('\n','').replace('\r',''));
}
if(stdout){
    log.info(stdout.replace('\n','').replace('\r',''));
}

Is there some other way I can get node.js to launch a file as another user without exposing the username and password?

I attempted to do it using powershell, but it seems SYSTEM is not allowed to launch files as other users.