Prospective Evaluation of the Incidence of PICS

The long-term goal of this study is to understand PICS in the pediatric population and how early medical and nutritional interventions may impact overall morbidity and survival, but first PICS must be characterized in the pediatric population. The hypothesize is that PICS occurs in pediatric critically ill patients and is associated with increased time to return to a baseline functional life post-injury or illness.

Enrollment/Randomization This is a prospective observational study with no randomization. The patients will be approached between PICU stay days 9-12 for consent. Labs will be drawn between PICU stay days 12-16 with a preference for PICU day 14, however, labs will be drawn in accordance with the standard of care labs to avoid additional draws.

Study Procedures

Specific Aim 1: To determine the incidence of PICS in the pediatric population and associate the diagnosis of PICS to survival and time to return to baseline functional life.

In order to determine the incidence of PICS in PICU patients, a prospective single-center study will be conducted of all critically ill pediatric patients admitted to PICU at Riley Hospital for Children at Indiana University Health, Indianapolis, IN. Patients will be included if they have an anticipated stay of >14 days in the PICU. Patients will be excluded from this study if they have are maintained on chronic mechanical ventilation, have a known chronic inflammatory disease process, or are diagnosed with failure to thrive or malnutrition upon admission to the PICU.

Data to be collected will include demographic data, nutrition data (weight, protein/non-protein calories received, type of nutrition and prescribed goal nutrition by a dietician), severity of illness, length of stay in the PICU and hospital. Existing routine labs from admission and PICU stay including blood counts, electrolytes and nutrition labs will be collected. At 14 days (± 1 day) the patient will be approached for inclusion into the study. At that time, routine labs to check for inflammation and nutritional status such as CRP, total lymphocyte count, albumin, prealbumin, and retinol binding protein will be collected Diagnosis of PICS will be determined when a patient has been admitted to the PICU for >14 days and has signs of both inflammation (CRP >15mg/L) and immunosuppression (total lymphocyte count < 0.80×109/L), as well as catabolism (Serum albumin < 3.0g/dL, Prealbumin <10mg/dL, Retinol binding protein <10μg/dL, and weight loss >10% or body mass index <18 during hospitalization).

Data Management:

Data will be entered and stored in in a de-identified/HIPAA compliant manner using a password protected web-based database that has securities to protect confidentiality and data integrity. The database will be constructed in REDCap.

Data Analysis Plan:

Clinical risk factors will be summarized and distributions examined. Relationships between the variables and the development of PICS will be explored using plots, correlation coefficients, and contingency tables. The association between clinical variables, including nutritional interventions, and PICS will then be analyzed with logistic regression. Both univariate and multivariate analyses will be conducted. The significance threshold p-value is set at 0.05.

Specific Aim 2: To determine if early increased inflammatory and immunosuppressive markers are associated with the development of PICS and increased morbidity and mortality.

Sample management and processing:

In addition to CRP and TLC, which will be collected at 14 days (± 1 day) of PICU admission , additional blood samples will be collected at these time points to be frozen for further analysis. At the time of blood collection, an additional 5 mL of blood will be collected, processed, and stored at -80 degree Celsius. Once desired time-points are identified and further funding obtained, samples will be processed in batches to evaluate biochemical markers of inflammation. This will be performed using The Inflammatory Cytokine Human Magnetic 5-Plex Panel for the Luminex™ platform. This will quantify GM-CSF, IL-1β, IL-6, IL-8 and TNF-α in serum samples.

The expected outcomes will focus on characterizing PICS in the pediatric population and identifying early inflammatory markers that may correlate with the development of PICS and subsequently increased morbidity associated with critical illness. The results are expected to have a positive impact by filling a key gap in the understanding of the mechanism of PICS in critically ill children. This research will provide insight into the interplay of inflammation, immunosuppression, and catabolism in critically ill children, which is imperative to the development of early therapeutic and nutritional interventions that can reduce morbidity and mortality associated with critical illness.