Forbindingen bliver ikke skiftet, før lægen kommer.

Because -en is the definite article attached to the noun.

• forbinding = bandage / dressing
• forbindingen = the bandage / the dressing

In Danish, the definite article is usually added to the end of the noun instead of being a separate word like English the.

This is the passive voice.

• skifte = to change
• skiftet = changed
• bliver skiftet = is changed / gets changed

So Forbindingen bliver ikke skiftet means The bandage is not changed.

This is a very common way to make the passive in Danish:

• blive + past participle

For example:

• Døren bliver åbnet. = The door is opened.

Danish often uses the present tense to talk about the future when the context already makes the timing clear.

In this sentence:

• bliver ikke skiftet = literally is not changed
• but in context it can mean will not be changed

The clause før lægen kommer clearly shows that the action is about a future situation, so Danish does not need a separate future form here.

In a normal main clause, ikke usually comes after the finite verb.

Here the finite verb is bliver, so:

• Forbindingen bliver ikke skiftet

Compare:

• Han kommer ikke. = He is not coming / He does not come.
• Døren er ikke åben. = The door is not open.

So the position of ikke here is completely normal.

Skiftet is the past participle of skifte.

You often use the past participle:

• with have in perfect tenses
• with blive in the passive

Examples:

• Jeg har skiftet forbindingen. = I have changed the bandage.
• Forbindingen bliver skiftet. = The bandage is being changed / is changed.

After før (before / until depending on context), Danish normally just uses the present tense if the meaning is future.

So:

• før lægen kommer = before the doctor comes / until the doctor comes

This is similar to English in sentences like:

• I’ll wait until he arrives not usually
• I’ll wait until he will arrive

So Danish and English are quite similar here.

Because før lægen kommer is a subordinate clause.

In the subordinate clause, Danish keeps the basic order:

• subject + verb
• lægen kommer

That is normal.

If you had ikke inside a subordinate clause, it would usually come before the verb:

• ... før lægen ikke kommer would be grammatically possible as word order, though the meaning would usually not fit this situation.

Compare the contrast:

Main clause

• Han kommer ikke.

Subordinate clause

• ... fordi han ikke kommer.

So this sentence is a good example of the difference between main clause and subordinate clause word order.

In this sentence, før is best understood as before in form, but the whole sentence often feels like English not ... until.

• Forbindingen bliver ikke skiftet, før lægen kommer.
• natural English meaning: The bandage won’t be changed until the doctor comes.

So even though før often corresponds directly to before, the combination ikke ... før is often translated as not ... until.

That is a very useful pattern to remember:

• ikke ... før = not ... until

Yes, but the meaning changes slightly.

• Forbindingen bliver ikke skiftet, før lægen kommer. = The bandage is not changed / will not be changed until the doctor comes. This sounds like a neutral statement about what happens.

• Forbindingen skal ikke skiftes, før lægen kommer. = The bandage is not to be changed / should not be changed until the doctor comes. This sounds more like an instruction, rule, or order.

So bliver describes what happens, while skal often expresses obligation or instruction.

Lægen means the doctor and is the most common modern word in Danish.

• læge = doctor
• lægen = the doctor

doktor exists too, but it is used differently and less often in everyday Danish for a medical doctor. In normal conversation about medical treatment, læge is usually the better word to learn first.

Yes. The exact English word depends on the medical context.

forbinding can refer to:

• a bandage
• a dressing
• material used to cover or protect a wound

So if you already know the situation, the translation may vary. Danish uses forbinding more broadly than English sometimes uses bandage.

It is natural and standard Danish, especially in a medical context.

It sounds like something you might hear:

• in a hospital
• at a clinic
• from medical staff
• in written instructions

So it is not unusually formal or strange. It is a very normal kind of sentence.

Sometimes Danish can use the s-passive, but in this sentence bliver skiftet sounds more natural.

Possible passive forms:

• Forbindingen skiftes ikke, før lægen kommer.
• Forbindingen bliver ikke skiftet, før lægen kommer.

Both are grammatical, but they can feel slightly different:

• skiftes often sounds a bit more general, formal, or instruction-like
• bliver skiftet often sounds more like an actual event or process

So the sentence you have is a very common and natural choice.