Brief Answer:
You need to give her supplemental oxygen.

Detailed Answer:
Thanks for your question on HealthcareMagic.
I can understand your concern.

The main function of the lung is to provide oxygen to the body.

So when one lung fails, supplemental oxygen should be given to match oxygen demand of the body.
So patient should take oxygen at least 16-18 hrs to relieve symptoms.

Supplemental oxygen is the most important thing which is helpful in respiratory failure.

Lung transplant is also an option. But it is for selected cases only.
So please let me know
1. What is the cause for her lung failure?
2. Is it since birth?
3. Was she a smoker?

Please reply me answers of above asked questions, so that I can guide you better. I will be happy to help you further.

Wish her good health.
Thanks.

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