Nutritional Interventions on Physical Functioning for Critically Ill Patients: An Integrative Review

Area of Science:

• Critical Care Medicine
• Nutrition Science
• Physical Rehabilitation

Background:

• Poor physical functioning (PF) is a significant challenge for critically ill patients in intensive care units (ICUs).
• While nutrition is believed to accelerate PF recovery, specific interventions and their impact across diverse ICU populations remain unclear.
• This study systematically synthesizes current evidence on nutritional interventions for PF in various ICU patient groups.

Purpose of the Study:

• To systematically review and synthesize the existing literature on nutritional interventions aimed at improving physical functioning in critically ill patients across different intensive care unit populations.
• To analyze the types of nutritional interventions, their timing, and their effects on physical functioning outcomes such as muscle mass, strength, and overall function.

Main Methods:

• A systematic literature search was conducted across major databases (PubMed, EMBASE, Web of Science, CINAHL Plus, Cochrane Library) from January 2010 to September 2020.
• Whittemore and Knafl's framework guided the review process, including independent record screening, data extraction, and quality appraisal by multiple reviewers.
• Manual searching of reference lists of included studies supplemented the database search.

Main Results:

• Twelve studies evaluated various nutritional interventions including early parenteral/enteral nutrition, goal-directed nutrition, higher protein/energy delivery, and intermittent enteral feeding.
• While overall function showed minimal improvement, muscle strength outcomes demonstrated the most significant positive effects.
• Mechanically ventilated patients were the most studied population, with interventions typically initiated within 24 to 48 hours of ICU admission.

Conclusions:

• Evidence on nutritional interventions for critically ill patients' PF is limited but generally of high quality.
• Further qualitative research is needed to explore optimal feeding initiation timeframes and patient/caregiver perspectives.
• More studies are warranted to advance the understanding and application of nutritional strategies for enhancing physical functioning in ICU survivors.