Any organisation, not just the NHS, can run a salary sacrifice scheme and then use the sacrificed salary to fund a lease.
Benefit for employer is that they do not pay employer pension or NI contributions on the sacrificed salary. In NHS and othe public sector this will be more than 30% and so it is a tangible saving for the employer whilst being seen as a perk for staff.
However, the NHS / public sector pension schemes are final or career average defined benefit schemes and taking a salary sacrifice will effectively reduce the level of the defined benefit.
Caveat emptor