Chronic Critical Illness: Application of What We Know

Abstract

Over the last decade, chronic critical illness (CCI) has emerged as an epidemic in intensive care unit (ICU) survivors worldwide. Advances in ICU technology and implementation of evidence-based care bundles have significantly decreased early deaths and have allowed patients to survive previously lethal multiple organ failure (MOF). Many MOF survivors, however, experience a persistent dysregulated immune response that is causing an increasingly predominant clinical phenotype called the persistent inflammation, immunosuppression, and catabolism syndrome (PICS). The elderly are especially vulnerable; thus, as the population ages the prevalence of this CCI/PICS clinical trajectory will undoubtedly grow. Unfortunately, there are no proven therapies to prevent PICS, and multimodality interventions will be required. The purpose of this review is to: (1) discuss CCI as it relates to PICS, (2) identify the burden on healthcare and poor outcomes of these patients, and (3) describe possible nutrition interventions for the CCI/PICS phenotype.

Persistent inflammation, immunosuppression, and catabolism and the development of chronic critical illness after surgery

“…Clinical protocols that include early mobilization and exercise, as well as adequate and consistent administration of protein and caloric requirements will likely be required as part of a multi-modality approach to therapy. (49) Dysfunctions in substrate utilization (rather than true deficits) are likely a key component to this catabolic state, meaning that adequate nutrition and/or physical rehabilitation alone are likely not sufficient therapies. Decreases in the metabolic/catabolic burden via administration of agents, such as propranolol and oxandrolone, have substantial therapeutic benefit in pediatric burn patients (50–52) but need further study in a broader, adult population of CCI subjects.…”

Chronic Critical Illness Patients Fail to Respond to Current Evidence‐Based Intensive Care Nutrition Secondarily to Persistent Inflammation, Immunosuppression, and Catabolic Syndrome

“…They fail to restore metabolic homeostasis (reflected by elevated GLP‐1) with an ongoing acute phase response (lower serum albumin levels) and persistent catabolism (trend toward higher ratios of urinary 3‐MH to creatinine). To date, our UF SCIRC studies support the PICS paradigm as the pathobiologic explanation for the development of CCI after sepsis . From a nutrition perspective, despite aggressive efforts to provide ICU EBG nutrition support, these patients have continued loss of lean muscle mass with severe functional disabilities, endure sepsis recidivism, and have poor dispositions to nonhome destinations, high rates of hospital readmissions, and poor 1‐year survival.…”

The Obesity Paradox in Sepsis: A Theoretical Framework

“…Due to the serious nature of sepsis, theories continue to emerge, and research is underway examining factors impacting the long-term effects of sepsis. The persistent inflammation, immunosuppression, and catabolism syndrome hypothesis builds on the chronic critical illness model and attempts to define a phenotype of critical illness (Kamel et al, 2018). The main tenet is that, given the excess energy stores in obesity, catabolism may not be as deleterious as it is in lean individuals.…”