If your sure she's not just trying to cool down, get her to a vet. I found this on poultrykeeper.com. There is also a picture that might help.
Signs and Symptoms
Infestation causes respiratory distress. Gasping for breath or 'gaping' as it is known is the biggest sign of gape worm. Shaking of the head and neck stretching are common. When birds are held, gurgling or a 'tracheal rattle' can often be heard. This can often be confused with respiratory infection, if in doubt, check for other signs of respiratory disease. If a heavy infestation occurs, death by suffocation will occur. Fully grown gape worms are 'Y' shaped and vary in size between 1 and 2cm long.
Treatment.
Chickens are particularly prone to respiratory diseases so it is important to ensuring you have a good worming schedule to eliminate the possibility of a respiratory problem being confused with a gape worm infestation. Gurgling noises that come from the throat of the bird can be caused by gapeworm and can be confused with a respiratory problem.
As with all internal parasites, there are many treatments that will kill these worms but rotating the grazing area will help to stop birds becoming re-infected. Internal Parasites or Worms in Chickens and Other Poultry provides some ideas for worming poultry. Flubenvet is licenced for use in poultry and will kill gapeworms.
Good luck and best wishes
Christine