Delirium is a common complication in critically ill patients accompanied by worse short- and long-term outcomes such as cognitive and functional impairments and mortality [1]. Guidelines recommend early mobilisation as part of a bundle to prevent and treat delirium [2].

The systematic review and meta-analysis from Nydahl and colleagues examined the effects of early mobilisation in critically ill adults on the risk and duration of delirium compared to usual care [3].

Following a rigorous search strategy, they included 13 studies (n = 2,164 patients) with low to moderate risk of bias. Their results showed that early mobilisation almost halved the risk of delirium onset (OR 0.53, CI 95% 0.34 to 0.83), though with significant heterogeneity. In addition, early mobilisation reduced delirium duration by a mean difference of -1.78 days (CI 95% -2.73 to -0.83) with no heterogeneity and based on three low-moderate risk studies. Sub-analyses revealed that delirium was best prevented with low-intensity exercises, out-of-bed mobilisation or mobilisation as part of a bundle.

However, earlier studies with a moderate risk of bias or before-after studies were more likely to have a significant effect when compared to low-risk studies such as randomised controlled trials. Mixed patient populations and different mobilisation types raise questions about potential responders and the appropriate intervention. While adverse events were rare, the influence of prolonged vertical positioning on cerebral blood flow remains unclear. Specifically, prolonged sitting was associated with worse outcomes in patients with an acute stroke [4].

Regrettably, many trials investigating early mobilisation in critical care have yet to assess delirium with a valid and reliable measurement instrument leading to their exclusion. In conclusion, this systematic review shows that early mobilisation is a promising intervention to prevent and treat delirium. However, the Authors also underline the need to investigate the effect of early mobilisation with rigorous methodology in larger randomised controlled trials.

STUDY STRENGTHS & LIMITATIONS

Strengths

• Prospective study protocol whereby two reviewers conducted the search, data extraction and risk of bias
• Report of delirium by means of valid and reliable outcome measurements
• Conclusions are highly supported by the data taking into account heterogeneity and publication bias

Limitations:

• Search strategy: 5 out of 13 publications were found by methods other than the described search strategy, potentially introducing selection bias.
• One Chinese study had to be excluded due to lack of access, increasing the chance of selection bias.
• Included studies were highly heterogenous in providing the intervention details, ranging from passive movement to mobilisation as part of a bundle, limiting the certainty of results and complicating treatment recommendations.

TAKE-HOME MESSAGES

This systematic review presented encouraging results about preventing and treating delirium, which is not usually connected to early mobilisation.
The results suggest the concept of early mobilisation to go beyond physical health by providing a holistic treatment with the potential for long-term cognitive improvements [5].

Therefore, critical care physiotherapists should consider delirium and include delirium assessment in their clinical practice. Early mobilisation should be considered on an individual patient basis until further studies about the recommended type, duration, and intensity for cognitive outcomes are available.

This article review was prepared and submitted by Alessia Ippolito (Istituto Mediterraneo per i Trapianti e Terapie ad Alta Specializzazione, ISMETT, Palermo, Italy) and Sabrina Eggmann (Universitätsspital Bern, Switzerland), on behalf of N&AHP and Physiotherapy interest group.