Were conquered professionals used as forced professional labor under Nazi rule?

It would be highly unusual for forced labor of concentration camp prisoners to be anything but simple manual labor. Reasons are that concentration camps and forced labor were death sentences. They weren't meant to be survived. And neither would the Nazis trust their inmates, nor would they keep them in good enough condition to trust their work results on a higher level. You can check whether a bolt is screwed on easily, but you cannot tell whether a doctors advice is solid or will kill you, without a second, reliable doctor. So why bother with the first one.

Someone sent to Auschwitz would be a prisoner. Weak, beaten, unable to function on a higher level because of what is done to them. Alternatively, they might be local to Auschwitz because they were colaborators and working there. But then I would not use the term "sent to". That implies they were inmates.

In Lithuania for example, the Nazis would recruit Hilfspolizei, auxiliary police units that did share in their oppressors crimes by for example guarding sites where people were shot. There is no reason to not recruit skilled labor for this. I guess every unit, if it becomes big enough, sooner or later has medical staff.

It seems that in contrast to the Intelligenzaktion in Poland, the Nazis did not murder the intellectuals per se. So a doctor that just stays put, has no other traits that the Nazi murderers would look for and just does their job might just fly under the radar.

And then there is the Memel region, that Germany annexed in the 1939 ultimatum to Lithuania. If born there to German parents back when it was part of Germany and not on the Nazis undesirables list, that doctor might have very little to fear and might even be "welcomed home".

So on average, it's either one or the other. Either you stood on the Nazis lists and it ended badly, or you did not. Keep in mind that the Nazis invaded once, the Sowjet troops even invaded twice, so being safe and colaborating with one of them might be a death sentence a year or two later when the other brutal regime waltzes in and kills their enemies.

The term "forced labor" implies actual prisoners forced to work. Obviously, occupied countries did not freely chose what to produce. So a skilled worker might still work in their factory, or job in general, but the Nazis control what is produced and how it's used. However, that is not normally called forced labor.

And in the end, we are talking about a world war. Millions and Millions of people. I cannot guarantee that what you picked as example did not happen to at least one person. War breeds strange biographies. But it would be highly unusual.

Expanding on the answer by jwenting, the outcome would strongly depend on the Nazi view of the racial 'suitability' of the workers. Those seen as almost 'Aryan' would get privileged jobs and conditions, other Western European workers less so, and Eastern European workers got the worst conditions.

Two factors would modify this, the time period and the willingness to submit to Nazi rule and rules, but again there was this hierarchy. Eastern workers would get punished more harshly for similar infractions, and their living conditions worsened faster.

Those who were privileged were not in the concentration and extermination camps. They would be in different grades of work camps, workers' hostels, farms, and urban housing. At the extreme end, some Dutch were recruited as teachers for German children. I once read (but couldn't find the reference again) about a Dutchman who absconded from a work camp, visited family, returned, and got told to please not do that again. A Polish or Russian worker in the same situation would have been shot.

The difference in treatment between, say, a French ex-POW on a German farm and an Ostarbeiter helped some Germans to ignore the plight of the Ostarbeiter. And the fate of the Hiwis could be even worse.

Under the Arbeitseinsatz a lot of people from the conquered territories were put to work in Germany. Mostly this was in labour intensive industries like farms, factories, and such places in order to free up German workers for the armed forces.

Being conscripted into the Arbeitseinsatz could theoretically happen to just about any adult (especially adult men, but also women and teenagers), but for doctors and other professionals critical to keeping the local society running (farmers, police, firefighters, etc.) this was not usually done, as the lists of those to be rounded up were created by local German authorities and those people were needed badly by those Germans as well. For example one of my grandfathers spent 3 years in Germany as a forced labourer under this scheme, he was a professional soldier before the war (and in May 1940 fought the Germans) and had few other skills to make him useful in his hometown to the occupying forces. My other grandfather was the local car mechanic who kept himself quite useful by maintaining the cars of the mayor and the local German Kommandantur, ensuring he would never get sent to Germany and his family always had food on the table (family legend has it that he used that position to also spy a bit on the Germans for the local resistance cell, but I've never been able to confirm this. Fact is that he never was called out as a collaborator after the war so there's probably some truth in it).

These people were certainly not treated nearly as badly as those in the concentration camps, but did fare worse than the Germans they worked with in their workplaces in Germany (mostly having smaller rations and more cramped living conditions, while of course being at the same or higher risk of falling victim to allied bombing raids on the factory complexes they were working at).

Another difference with the general population of concentration/extermination camps was that they were usually conscripted only for a limited period, though this may or may not have been always honoured by the Germans (e.g. my grandfather was sent home in 1944 after having been in Germany for 3 years, many people were sent home after a year, sometimes 2).