Physiological barriers to oral intake in survivors of critical illness: A scoping review

Oral nutrition is the predominant mode of nutrition delivery on the post-Intensive Care Unit (ICU) ward; yet, it is associated with lower intake than via enteral or parenteral nutrition. There are limited data on barriers that influence oral intake in ICU survivors. Therefore, we conducted a scoping review to map and describe physiological nutrition-impacting symptoms following ICU discharge. Database searches of MEDLINE, Emcare, and CINAHL identified primary research in English that included adult patients eating orally throughout the post-ICU period. Data were extracted on study design, aim, population, post-ICU setting, and the physiological nutrition-impacting symptoms reported, including method of reporting and symptom prevalence. Twenty-nine studies comprising between 11 and 357 participants were included, most of which were prospective and observational in design. Post-ICU settings varied and were inclusive of acute care wards (n = 7, 23%), rehabilitation facilities (n = 5, 16%), and various timepoints following hospital discharge (n = 19, 61%). Key physiological nutrition-impacting symptoms reported were dysphagia (n = 25, 86%) and poor appetite (n = 10, 34%). Other common symptoms included early satiety, fatigue, and nausea. Variations occurred in both the method used to quantify symptoms and the prevalence of each symptom across isolated timepoints. The proportion of patients reporting at least one nutrition-impacting symptom at each time point was 16%-78% on the acute care ward, 29%-95% in rehabilitation facilities, and 10%-71% following hospital discharge. Further studies are required to determine which symptoms ICU survivors experience and their trajectory and impact on oral intake.