How Differences in the Disease Process of the COVID-19 Pandemic Pose Challenges to the Delivery of Critical Care Nutrition

Abstract

Purpose of review: The COVID-19 pandemic is a unique disease process that has caused unprecedented challenges for intensive care specialists. The hyperinflammatory hypermetabolic nature of the disease and the complexity of its management create barriers to the delivery of nutritional therapy. This review identifies the key differences which characterize this pandemic from other disease processes in critical illness and discusses alternative strategies to enhance success of nutritional support.

Recent findings: Prolonged hyperinflammation, unlike any previously described pattern of response to injury, causes metabolic perturbations and deterioration of nutritional status. High ventilatory demands, hypercoagulation with the risk of bowel ischemia, and threat of aspiration in patients with little or no pulmonary reserve, thwart initial efforts to provide early enteral nutrition (EN). The obesity paradox is invalidated, tolerance of EN is limited, intensivists are reluctant to add supplemental parenteral nutrition (PN), and efforts to give sufficient nutritional therapy remain a low priority. The nature of the disease and difficulties providing traditional critical care nutrition lead to dramatic deterioration of nutritional status. Institutions should not rely on insufficient gastric feeding alone but focus instead on redoubling efforts to provide postpyloric deep duodenal/jejunal EN or re-examine the role of supplemental PN in this population of patients with such severe critical illness.

Keywords: COVID-19 disease; Coronavirus; Enteral nutrition; Malnutrition; Nutritional therapy; Parenteral nutrition; SARS-CoV-2.

Fig. 1

Classification of SARS-CoV-2 Virus (Figure adapted with permission from H A. Aboubakr et al. and Galanopoulos M et al. – references [3, 4]). Legend: SARS severe acute respiratory syndrome, MERS Middle Eastern respiratory syndrome, SARS-CoV-2 severe acute respiratory syndrome coronavirus-2

Fig. 2

The Obesity Paradox (figure reproduced with permission from D L. Davenport et al. – reference [14])

Fig. 3

Prioritization of responsibilities in the complex management of the critically ill patient with COVID-19 disease. Legend: PPE personalized protective equipment, Rx therapy

Fig. 4

Comparison of the metabolic response to injury in COVID-19 disease (a) (figure adapted with permission from J Whittle et al. – reference 18) to previously described models: Cuthbertson Ebb/Flow (b) (figure reproduced with permission from JS Carson et al. – reference [19]). SIRS/CARS (c) and PICS (d) (figures reproduced from B Mathias et al. – reference [20]). Legend: SIRS systemic inflammatory response syndrome, CARS compensatory anti-inflammatory response syndrome, PICS persistent inflammatory catabolism syndrome

Fig. 5

Pattern of antioxidant micronutrients in response to metabolic stress (figure reproduced with permission from MM Berger – reference [39]). Legend: AOX antioxidant

Fig. 6

Choice of institutional strategies to provide optimal nutritional therapy in COVID-19 disease: early initiation of small bowel feeding (a) (reproduced with permission from Chris Gralapp) versus gastric feeding with early supplementation of parenteral nutrition (b) (reproduced from Maria Palma – reference [68])