"Front Lines" meaning deployed on Coast Guard Cutters. What chat were you participating in? I'm just curious.
First, I should state that I am not a member of the medical profession and that my experience with Coast Guard medical personnel is limited to routine/required appointments and the occasional cold pack or seasickness pill.
That being said, if you were told that physicians are deployed to "heal wounds on the front lines," the person you were speaking to was most likely referring to the Coast Guard's enlisted rated personnel known as Health Services Technicians or HS. They are basically the equivalent of civilian nurses/maybe physician assistants. Each major cutter has a permanently assigned HS that is responsible for the crew's health and well being. They manage the crew's medical records and treat minor injuries and illnesses. If something was to happen that required surgery or could lead to loss of life, the HS responds similar to how an EMT or Paramedic would. They provide the initial first aid and triage, gather all necessary information/stats and then contact the Flight Surgeon located on land to brief him/her on the situation as well as make a recommendation on whether or not to conduct a medevac. That is the extent of a "front line" HS's surgical experience. Now, if some crazy, out there situation occurred where the cutter was unable to get someone off the cutter or a surgeon on, MAYBE the HS would be forced to take more extreme action but with technology and communication being what it is, that is highly unlikely. The most "surgery" I've ever seen an HS do on their own was stitches.
If you desire to be a surgical nurse, then the Coast Guard would be the wrong service to want to work with. You are better off trying to go to the Navy or Army. As someone in line for surgery next year, I am receiving all treatment at the local Naval Hospital, which is a recognized Military Treatment Facility. There is no Coast Guard involvement medically, only a couple of signatures from PHS doctors assigned to the Coast Guard giving their recommendation that I receive the surgery.
Listen to kp2001, he is our military medical expert on this forum. He knows what he is talking about.