The effects of immersion in shoulder-deep water on spirometry in SCI have been studied. While immersion in water does not represent a treatment modality for pulmonary function, the effects of immersion are important to note from a clinical perspective because many subjects with SCI undergo pool-based therapy that exposes them to shoulder-deep immersion in water.
Immersion in shoulder-deep water results in changes in lung function tests in subjects with tetraplegia. Bosch and Wells (1991) showed that in comparison to able-bodied and subjects with paraplegia, subjects with tetraplegia have a significant decrease in residual volume with immersion. In a pre-post trial involving 23 motor complete subjects with tetraplegia and 11 healthy controls, Thomaz et al. (2005) concluded that overall, immersion in water appeared to improve breathing mechanics in subjects with tetraplegia.
There is level 4 evidence (based on 1 pre-post study) (Thomaz et al. 2005) that the use of immersion to shoulder-deep 33-34° C water improves pulmonary function immediately in persons with tetraplegia but longer terms effects have not been evaluated.