Reactive medical devices

1. A tracheal tube comprising a nematic polymer or nematic elastomer, or a combination thereof, wherein an outer diameter of the tracheal tube changes in size in response to exposure of the tracheal tube to a light source or to a heat source, or a combination thereof.

2. The tracheal tube of claim 1 , wherein the tracheal tube comprises at least the light source or the heat source, or a combination thereof.

3. The tracheal tube of claim 2 , wherein the light source comprises a fiber optic wire.

4. The tracheal tube of claim 2 , wherein the light source comprises the heat source.

5. The tracheal tube of claim 1 , wherein the change in size comprises an increase in size of the outer diameter of the tracheal tube.

6. The tracheal tube of claim 1 , wherein the change in size comprises a decrease in size of the outer diameter of the tracheal tube.

7. The tracheal tube of claim 1 , wherein at least the nematic polymer or the nematic elastomer comprises a polymer of the monomer liquid-crystal p-azoxyanisole, and wherein the monomer liquid-crystal p-asoxynisole comprises the structure:

8. The tracheal tube of claim 1 , wherein at least the nematic polymer or the nematic elastomer comprise a side-chain nematic polymer comprising pendant mesogens and having the structure:

wherein n is at least 10.

9. A tracheal tube comprising:

a nematic polymer; and

a dye that undergoes isomerization upon exposure to a light source or a heat source, or a combination thereof, wherein isomerization of the dye disrupts a nematic order of the nematic polymer.

10. The tracheal tube of claim 9 , wherein the disruption of the nematic order due to isomerization of the dye contracts the diameter of the tube.

11. The tracheal tube of claim 9 , wherein the nematic polymer comprises a main chain nematic polymer or a side chain nematic polymer, or a combination thereof.

12. The tracheal tube of claim 9 , wherein at the nematic polymer is crosslinked to form a nematic elastomer, and where the tracheal tube comprises the nematic elastomer.

13. The tracheal tube of claim 9 , wherein isomerization of the dye comprises isomerizing trans isomer molecules of the dye to cis isomer molecules of the dye.

14. The tracheal tube of claim 9 , wherein the dye comprises azobenzene.

15. The tracheal tube of claim 14 , wherein isomerization comprises transforming trans isomers of the azobenzene to cis isomers of the azobenzene according to following the structures:

16. The tracheal tube of claim 9 , wherein the light source comprises a source of ultraviolet light, and the nematic polymer undergoes isomerization upon exposure to the ultraviolet light.

17. A tracheal tube system comprising:

an energy source; and

a tracheal tube comprising a nematic polymer or nematic elastomer, or a combination thereof, wherein an outer diameter of the tracheal tube changes in size in response to exposure to the energy source when the energy source is active.

18. The tracheal tube system of claim 17 , wherein the energy source comprises a light source or heat source, or a combination thereof.

19. The tracheal tube system of claim 17 , wherein the energy source is integrated with the tracheal tube.

20. The tracheal tube system of claim 17 , comprising an insertion rod, wherein the energy source is disposed on the insertion rod.