Development and validation of the PICS-index to assess the severity of the syndrome of consequences of intensive care: a descriptive, prospective, and unmatched cohort study

INTRODUCTION: The post intensive care syndrome (PICS) is a clinical manifestation of “learned non-use” phenomena, resulting from the application of metabolic rest strategies such as bed rest, sedation, and ventilation. This leads to prolonged, multifocal dysfunction in vital functions. The lack of standardized diagnostic methods for this syndrome limits its study. For the diagnosis of PICS, we combined 15 signs of vital function disturbances that have the greatest impact on quality of life, with a scoring value of 0.5–1. The sum of these symptoms has been designated as the PICS-index. OBJECTIVE: To develop a scale for calculating the PICS-index with stratification of its values into three ranges of severity: mild, moderate and severe. MATERIALS AND METHODS: A descriptive, prospective, and unmatched cohort study was conducted on 169 patients who had a high dependency on medical care and were admitted to a rehabilitation center between 2022 and 2023. RESULTS: Using the PICS-index, showed that 100 % of patients who spent more than 72 hours in the ICU during the early recovery period (up to 6 months) developed PICS, with a predominance of moderate cases (35–52 %). The proportion of severe PICS forms reached its maximum (37 %) between 3 and 6 months. In the late recovery phase (more than 6 months), mild PICS forms were predominant (45 %). The severity of PICS was influenced by the duration of ICU stay and the timing of mechanical ventilation, but not the age of patients. CONCLUSIONS: The PICS-index is a clinically effective tool for the multidisciplinary diagnosis and assessment of the severity and progression of PICS. Using the PICS-index, we have devised a method for evaluating the predominance of specific signs. The most common signs are disturbance of the gravitational gradient, polyneuromyopathy, dysphagia. This confirms the essence of PICS as a clinical manifestation of the "learned non-use" phenomenon.