Projects

Abstract

How to cite this article: Narayan SK, Gudivada KK, Krishna B. Assessment of Nutritional Status in the Critically Ill. Indian J Crit Care Med 2020;24(Suppl 4):S152–S156.

Keywords: Critically ill adults, Intensive care, Malnutrition, Nutritional assessment, Nutritional status

Introduction

In critically ill patients, the prevalence of malnutrition ranges between 38% and 78%. At admission to hospital, at least one-third of patients have some degree of malnutrition and two-thirds of them progress to further decline without adequate nutritional provision. Additionally, two-thirds of patients who were without malnutrition will become malnourished during hospitalization.1–3 Many studies have shown that malnutrition is an independent risk factor for nosocomial infections and higher readmissions rates. Early identification and appropriate nutritional intervention in malnourished patients has consistently shown to decrease hospital stay, infectious complications, and overall cost.4 Nutritional assessment in critically ill patients is challenging, best method to identify patients susceptible to malnutrition has not yet been identified. Various risk factors and nutritional risk scores have been proposed. In this review article, we will be discussing briefly on the pathophysiology of malnutrition, the importance of nutritional risk screening (NRS 2002) and assessment, and finally the practical implications of bedside nutritional assessment.

Malnutrition in Critically Ill: Pathophysiology

Malnutrition is defined as any variation in degree of nutrition (either overnutrition or undernutrition) with or without inflammation that has led to variations in body composition.5 According to a consensus statement by the Academy of Nutrition and Dietetics (AND) and the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) malnutrition is defined as the presence of any two or more of these entities: Insufficient energy, intake, weight loss, loss of muscle mass, loss of subcutaneous fat, localized or generalized fluid accumulation, or decreased functional status.6 Critical illness is a life-threatening condition characterized by infection, trauma, or any medical illness. It involves massive surge of proinflammatory mediators, which incites host catabolism. Proinflammatory response to infection or trauma is body's adaptive mechanism to defend against pathogens and to supplement substrates for healing. However, severe proinflammatory response is counterproductive; hence, body mounts an anti-inflammatory response to counterbalance the damage. On occasions when the balance shifts toward excess anti-inflammatory state, the immune paralysis thus created may not be effective enough to eradicate the pathogens.7 Therefore, a delicate balance should exist between pro- and anti-inflammatory states to facilitate appropriate host immune response. Nutrition plays a vital role in modulating host immune response, maintaining muscle mass, slowing catabolism, and maintaining gastrointestinal mucosal integrity and immunity (Flowchart 1).8