How can a collapsed nose be fixed?

It depends on what exactly has collapsed but techniques can be employed to definitely help you with your breathing and the aesthetics of the nose.  Photos would be needed to help assess the extent of the procedure.  Cartilage grafting techniques, placing certain cartilage grafts in the nose would be used to structurally reinforce the nose and prevent future collapse.  

Hello and thank you for your question. Based on your
description, you have external nasal valve collapse.  This can be fixed with alar batten grafts.  Make sure you specifically look at before and after
pictures of real patients who have had this surgery performed by your surgeon
and not just a computer animation system. The most important
aspect is to find a surgeon you are comfortable with. I recommend that you seek
consultation with a qualified board-certified plastic surgeon who can evaluate
you in person.
Best wishes and good luck.
Richard G. Reish, M.D.
Harvard-trained plastic surgeon

Yes this can be repaired to give your nose the support it needs to prevent the collapse. This is usually done with cartilage grafts to maintain support. See a very experienced rhinoplasty surgeon who can show u photos of his patients like you who have had this done.

Rhinoplasty is a surgery to improve the shape of the nose for breathing or appearance.A collapsed nose may occur when the nose has lost its structural support either from trauma, infection, cocaine abuse, or repeat surgery. Fixing the nose requires replacement of the structures that hold the shape of the nose so it does not collapse. This will make the nose stiffer or more rigid. Your nose will be need to be examined to diagnose where the collapse is happening. You may need rib cartilage to recreate your nasal support. I would consult with a rhinoplasty surgeon who understands rib harvesting and grafting for a safe and happy outcome. Safety comes first. 

There are many different types of collapses that can occur in the nose such as collapsing of the lower lateral cartilages, collapsing of the upper lateral cartilages, collapsing of the dorsal septum, and collapsing of the nasal bones. Each one of these issues are treated differently. To treat a collapsed alar rim requires an alar rim graft to support the lower lateral cartilages. To  treat a collapsed upper lateral cartilage requires a spreader graft. A bone graft is required for collapsed nasal bones. A cartilaginous onlay graft is required to treat a saddle nose deformity of the nasal dorsal cartilage. For more information and many  before and after rhinoplasty examples, please see the link and the video below

It sounds from your description that you have external valve collapse when you breathe in.The unilateral swelling you are describing is likely normal cyclical swelling which occurs throughout the day but can be especially noticeable when sleeping. Although, it is possible that ANY surgery of the nose can have complications or cause breathing problems, there are treatment options which are specifically designed to treat external valve collapse. Often times, this requires strengthening and supporting your nostril area with cartilage grafts to keep the airway (external valve) open when you breathe in. It is important to have an in-office endoscopic examination to determine what is causing your breathing difficulties. There may other internal anatomical issues which are making it difficult to breathe. Hope this helps!Johnson C. Lee, MD Plastic Surgery

A collapsed nose requires bringing in more infrastructural support which includes1)alar contour grafts for the nasal opening2)alar batten grafts for the mid vault3)diced cartilage and cantilever grafts for the dorsum

The technique to fix a collapsed nose and improve the airway depends on the cause and location of the collapse but usually involves the placement of cartilage grafts to provide structure and support. Consult with a rhinoplasty specialist who does a lot of nasal trauma and revisions because they will be experienced in these grafting techniques.