High- and low-intensity inspiratory muscle training (IMT) have comparable effects in patients with weaning difficulties

Introduction IMT improves respiratory muscle function in patients with weaning difficulties. It is unknown if IMT improves clinical outcomes and respiratory function. Aim Assessing the effect of high-intensity IMT (H-IMT) vs. sham low-intensity IMT (L-IMT) on clinical outcomes and respiratory function in patients with weaning difficulties. Methods Patients performed daily IMT sessions (4sets, 6–10 breaths) until weaning success or 28 days. H-IMT group (n=43, 27%male, age:57±15y) trained at the highest tolerable external load (30-50% maximal inspiratory pressure, PImax) and L-IMT group (n=45, 24%male, age:60±12y) at max.10%PImax. Results Both groups had high weaning success rates. In successfully weaned patients, trends to a shorter weaning duration and ICU stay in the H-IMT than L-IMT group were observed (Table 1). Both improved PImax and vital capacity significantly, with H-IMT yielding greater vital capacity gains. H-IMT improved peak inspiratory flow and rapid shallow breathing index, yet not significantly different from L-IMT. Conclusions Both IMT protocols have similar benefits on weaning outcomes, consistent with prior studies on IMT, yet H-IMT tended to reduce weaning duration and ICU stay. While both improved respiratory muscle function, H-IMT had greater impact on pulmonary function. More studies needed to optimise the IMT protocol and asses internal load impact on inspiratory muscles.