One very important aspect of hair transplantation is graft survival. Without the grafts alive there is no hair transplant result. Grafts are relatively delicate pieces of tissue. FUE grafts tend to be more delicate then FUT grafts. They generally have less fatty tissue surrounding the follicular unit to protect them.
Grafts can be damaged at any point during the hair transplant. From the initial extraction to cleaning and trimming. To the placement back in the recipient area of the patient. They need to be handled with great care. Under microscope or loupes to ensure their survival and at no point, the bulb is crushed. Although delicate they can be surprisingly resilient. If looked after correctly can stay out of the skin for a number of hours.
Whilst out of the skin they are kept in a holding solution. Studies have shown that grafts can survive at about a 90% rate for up to 4 hours. Though reports have shown extreme cases of grafts lasting 24 hours.
Generally, the solution is made up of saline, often it is 0.9% sodium chloride. It is the same thing they put in you during an ER visit or for re-hydration.
Medical development and biotech companies are constantly looking at ways to improve skin healing and this maybe able to used in the handling and holding of grafts.