Early physical and occupational therapy within the initial 96 hours of mechanical ventilation is associated with improvement in a patient’s level of cognitive impairment, neuromuscular weakness, and quality of life at 1 year, investigators reported in The Lancet Respiratory Medicine.
Mechanical ventilation (MV) can lead to prolonged cognitive impairment. Researchers assessed whether early mobilization (ie, physical and occupational therapy) could reduce cognitive impairment and other post-MV-related disabilities 1 year after critical illness.
The investigators conducted a single-center, parallel, randomized controlled trial of adults at an urban academic hospital who were admitted to the medical-surgical intensive care unit (ICU) and required mechanical ventilation. Study enrollees were functionally independent at baseline (Barthel score >70) and mechanically ventilated for less than 96 hours but expected to continue MV for at least 24 hours.
The participants were randomly assigned 1:1 to either early mobilization at enrollment (ie, the intervention group) or to usual care, in which physical and occupational therapy were provided only when requested by the primary team.
The primary endpoint was cognitive impairment at 1 year based on a Montreal Cognitive Assessment (MoCA) score of less than 26. Participants were assessed for eligibility from August 11, 2011, to October 24, 2019.
A total of 99 patients were in the usual care group (median age, 54.5 years; 56% male) and 99 patients were in the early mobilization group (median age, 57.9 years; 59% male) and comprised the intention-to-treat analysis. At 1 year, 144 patients were alive (75% in the usual care group, and 71% in the intervention group), and 88% of those in the usual care group and 89% of those in the intervention group received follow-up testing for cognitive impairment.
In the usual care group, 43% of patients had cognitive impairment at 1 year compared with 24% of those in the intervention group (absolute difference -19.2%; 95% CI, -32.1 to -6.3; P =.0043). The intervention group had a higher median MoCA score at 1 year compared with the usual care group (26 [interquartile range [IQR], 24-28] vs 23 [IQR, 21-26]; P =.0001). Fewer patients in the intervention group vs usual care group had cognitive impairment at hospital discharge (54% vs 69%; absolute difference, -15.2%; 95% CI, -28.6 to -1.7; P =.029).
The intervention group had a higher proportion of patients with functional independence compared with the usual care group at hospital discharge (P =.0041), but it was not statistically different at 1 year (P =.66).
At 1 year, the intervention group vs the usual care group had fewer ICU-acquired weaknesses (none vs 14%, respectively; absolute difference, -14.1%; 95% CI, -21.0 to -7.3; P =.0001) and higher Medical Outcomes Study Short Form-36 (SF-36) physical component scores in quality-of-life testing (median 52.4 [IQR, 45.3-56.8] vs median 41.1 [IQR, 31.8-49.4], respectively; P <.0001). The SF-36 mental component scores were not significantly different between the 2 groups at 1 year (P =.98). In addition, the median number of institution-free days was not significantly different between groups (usual care group, 335 days [IQR, 121-356] vs intervention group, 338 days [IQR, 111-355]; P =.88).
Adverse events, including tachycardia, hypotension, and tachypnea, occurred in 6% of patients in the intervention group and in none of the participants in the usual care group (P =.029).
Study limitations include the large effect size and modest sample size, as well as the low rate of mobilization in the control group. Also, the screening tool for cognitive function could overestimate the prevalence of impairment, the premorbid cognitive function of the cohort was unknown, and the single-center design limited generalizability. Furthermore, in the intervention group, the small numbers of patients who did not receive early mobilization and/or were lost to follow-up could have led to measurement bias and random confounding.
“Our study suggests that implementing complex multidisciplinary interventions, such as early mobilization in the acute phase of critical illness, into practice has substantial benefits on long-term disability in surviving patients after mechanical ventilation,” the study authors commented.
Patel BK, Wolfe KS, Patel SB, et al. Effect of early mobilisation on long-term cognitive impairment in critical illness in the USA: a randomised controlled trial. Lancet Respir Med. Published online January 20, 2023. doi:10.1016/S2213-2600(22)00489-1