In-Patient Trajectories and Effects of Training in Survivors of COVID-19-Associated Acute Respiratory Failure.

Background: Pulmonary rehabilitation (PR) is useful in survivors of COVID-19-associated acute respiratory failure (ARF). The aim of this retrospective study on in-patient PR was to report rehabilitative trajectories and effects of cycle training.

Methods: According to the Short Physical Performance Battery (SPPB) score at admission (T0), participants were allocated to stage 1 (SPPB < 6), stage 2 (SPPB ≥ 6 and < 10), or stage 3 (SPPB ≥ 10) and performed increasing level of activities from passive exercises to free walking, balance exercises, strength exercises, and tailored cycle-ergometer endurance training. The primary outcome was SPPB. 6-min walk distance (6MWD), Medical Research Council score, Barthel dyspnea index, and rate of subjects able to cycling were also assessed.

Results: Data of 123 participants were analyzed. At T0, 44 (35.8%), 50 (40.6%), and 29 (23.6%) participants were allocated to stages 1-3, respectively. At discharge, participants showed significant improvements in SPPB, independent of the initial stage, 81 (65.8%) improving more than its minimal clinically important difference. At T1, the proportion of participants in stages 1 and 2 decreased, whereas significantly increased in stage 3 ( = .003), (being 9.8%, 33.3%, and 56.9% for stages 1-3, respectively; <.001). Sixty-nine of 123 participants (56.1%) underwent cycle exercise training. In participants able to perform it, 6MWD improved by 115 (65-240) m and 60 (40-118) m in participants with and without exercise-induced desaturation, respectively, with significant difference between groups ( = .044).

Conclusions: In-patient PR could be tailored and progressively increased to survivors of COVID-19-associated ARF; cycle training was feasible in half of the participants. Benefits were independent of initial stage of physical performance and allowed participants to move from lower to higher levels of activities.