Absolutely.
However, I see you're up in Marion. They won't call up Columbus Approach until just prior to entering their airspace (Class C or Charlie airspace). The northern boundary of that airspace is in southern Delaware County, and they cruise at pretty a low altitude. What that means in this case, is you may or may not hear them due to VHF and line of sight. This is of course dependent on your antenna setup. If they cruised at 10,000' you'd hear them in Marion for sure. But with low altitude and not calling up until just outside the city, I don't know. Give it a try though, if you haven't already! Coming from the north, they would call up Columbus Approach on 125.950.
When they do talk to ATC, they will identify as "Medflight #" and will state their intentions. If they are
actively transporting a patient to the hospital, their callsign is prefixed with "MEDEVAC". An example would be, "Columbus approach, Medevac Medflight 6 is over Hoover Reservoir at 3000' inbound to Grant Hospital, requesting transition". As
@tvfd700 mentioned, aside from talking to ATC they use 123.025 in large metro areas. Here in Columbus .025 is a pretty busy frequency.
The reason you won't often hear them with a good signal in Marion is because that's (for ease of explanation) uncontrolled airspace, where they are generally not in contact with ATC. Hope that helps!