Inspiratory muscle training is feasible and safe for patients with acute spinal cord injury

Abstract

Objective: To investigate the feasibility and safety and, to a lesser extent efficacy, of inspiratory muscle training (IMT) for patients with acute complete cervical or thoracic spinal cord injury (SCI).

Design: Prospective, observational pilot study comprising a series of case reports.

Setting: Tertiary care, public hospital.

Participants: Seven adult subjects with an acute complete cervical or thoracic SCI.

Interventions: Participants received IMT as soon as their respiratory condition was stable. A high-resistance, low-repetition program of IMT using a POWERbreathe KH1 device was instituted. Training comprised 3-6 sets of 6 breaths, commenced at 50% maximum inspiratory pressure with the training load progressively increased.

Outcome measures: Feasibility (number of sessions when the criteria to participate in IMT were met/not met), safety (symptoms and physiological stability) before, during and after IMT sessions and efficacy (lung function) were measured.

Results: There were 50 sessions in total where participants met the criteria to receive IMT, with a mean (range) of 7.1 (3-11) IMT sessions per participant delivered over 10.7 (4-17) days. IMT was feasible, with all 50 planned sessions of IMT able to be delivered, and safe, with stable physiological parameters and no adverse symptoms or events recorded before, during or after IMT. Maximal inspiratory pressure increased for four participants and forced vital capacity increased for three participants over the duration of their IMT sessions.

Conclusion: A high-resistance, low-repetition program of IMT was feasible and safe in adults with an acute complete cervical or thoracic SCI whose respiratory status was stable.

Trial registration: Australian New Zealand Clinical Trials Registry (ACTRN 12614000975695).

Keywords: Breathing exercises; Respiratory muscle training; Safety; Spinal cord injuries.

Figures

Figure 1

POWERbreathe KH1 device.

Figure 1

POWERbreathe KH1 device.

Figure 2

Flow of participants through the trial. C, cervical; FVC, forced vital capacity; n, number; SCI, spinal cord injury; T, thoracic.

Figure 2

Flow of participants through the trial. C, cervical; FVC, forced vital capacity; n, number; SCI, spinal cord injury; T, thoracic.

Figure 3

PImax variability between and within participants across IMT sessions.

Figure 3

PImax variability between and within participants across IMT sessions.

Figure 4

FVC variability between and within participants across IMT sessions.

Figure 4

FVC variability between and within participants across IMT sessions.

Figure 5

Training loads across IMT sessions.

Figure 5

Training loads across IMT sessions.