Congratulations, your success in the medical field has not gone unnoticed! Once you have clocked at least ten hours as a Doctor, you can upgrade to the better-paying and more challenging role of surgeon. While doctors have at least a casual understanding of surgery, you are expected to be closely familiar with the surgical arts. If you have a Head Surgeon available, obey their orders as far as triage is concerned, keep your hands washed and your tools sterilized, and don't accidentally sew any orifices shut, and you should have a long career as a Surgeon. Do note that in the absence of other medical professionals you are expected to be capable of normal doctoring activities, and that you may be required to do field work away from your precious clean Medbay, so a familiarity with 'ghetto surgery', as it were, will also help you.