Critical Nutrition Requirements in the Critically Ill


In today’s era of heart attacks and strokes, admission into an intensive care unit (ICU) may be life-saving. Chances are that you have a loved one or a friend who has recently been admitted into the ICU. Here is a nutritional perspective on these cases.

When an individual becomes critically ill, the body responds by triggering “stress mechanisms” aimed at providing energy to vital organs. The body uses its stores to produce energy and activates the production of substances that can help it deal with the injury.1This results in various consequences, including increased energy expenditure, high blood sugar and loss of muscle mass.

Patients who are critically ill often have difficulties maintaining optimum nutritional intake. Thus, these individuals usually lose weight rapidly, resulting in slower recovery and poor outcomes.2 Nutritional support then becomes crucial in order to meet energy requirements and prevent malnutrition in these patients.

The nutritional requirements of the critically ill, however, is complex.1 Caloric intake should closely match the energy expenditure of the patient. Protein intake should adequately provide the building blocks required for tissue repair and maintenance, and to prevent depletion of the body’s supply of amino acids that are essential for stress responses. Whey protein, in particular, contains all the essential amino acids that the body cannot produce on its own. Some oral nutrition supplements contain whey that is already hydrolysed, or broken down into its component amino acids, allowing faster absorption.

Vitamins and minerals, although usually required only in small quantities, are also vital to many bodily functions that are crucial for repair and recovery.

Studies have identified specific nutrients that may have beneficial effects on the immune system, metabolism and gastrointestinal function. Arginine, omega-3 fatty acids, antioxidants and nucleotides are some of the components now being added to produce so-called ‘immune-modulating’ or ‘immune-enhanced’ diets. These components are thought to enhance immune function, and have been reported to aid wound healing and reduce hospital stay.1,2

In many of critically ill patients, nutrition support can be done through a feeding tube. It is important to use solutions that can deliver consistent amounts of readily-absorbed nutrients and can be easily adjusted to tailor to the requirements of each individual patient. 

Administered properly, nutritional support in critical care can help preserve and improve bodily functions, hasten recovery, and most importantly, save lives.

  1. Preiser JC, van Zanten AR, Berger MM, et al. Crit Care. 2015;19:35.
  2. Debaveye Y, Van den Berghe G. Annu Rev Nutr. 2006;26:513-538.