Chronic critical illness and post-intensive care syndrome: from pathophysiology to clinical challenges
- PMID: 35779142
- PMCID: PMC9250584
- DOI: 10.1186/s13613-022-01038-0
Chronic critical illness and post-intensive care syndrome: from pathophysiology to clinical challenges
Abstract
Background: Post-intensive care syndrome (PICS) encompasses physical, cognition, and mental impairments persisting after intensive care unit (ICU) discharge. Ultimately it significantly impacts the long-term prognosis, both in functional outcomes and survival. Thus, survivors often develop permanent disabilities, consume a lot of healthcare resources, and may experience prolonged suffering. This review aims to present the multiple facets of the PICS, decipher its underlying mechanisms, and highlight future research directions.
Main text: This review abridges the translational data underlying the multiple facets of chronic critical illness (CCI) and PICS. We focus first on ICU-acquired weakness, a syndrome characterized by impaired contractility, muscle wasting, and persisting muscle atrophy during the recovery phase, which involves anabolic resistance, impaired capacity of regeneration, mitochondrial dysfunction, and abnormalities in calcium homeostasis. Second, we discuss the clinical relevance of post-ICU cognitive impairment and neuropsychological disability, its association with delirium during the ICU stay, and the putative role of low-grade long-lasting inflammation. Third, we describe the profound and persistent qualitative and quantitative alteration of the innate and adaptive response. Fourth, we discuss the biological mechanisms of the progression from acute to chronic kidney injury, opening the field for renoprotective strategies. Fifth, we report long-lasting pulmonary consequences of ARDS and prolonged mechanical ventilation. Finally, we discuss several specificities in children, including the influence of the child's pre-ICU condition, development, and maturation.
Conclusions: Recent understandings of the biological substratum of the PICS' distinct features highlight the need to rethink our patient trajectories in the long term. A better knowledge of this syndrome and precipitating factors is necessary to develop protocols and strategies to alleviate the CCI and PICS and ultimately improve patient recovery.
Keywords: Acquired immunosuppression; Chronic critical illness; Cognitive impairment; ICU sequelae; Long-term outcome; Neuromuscular disorders; Post-ICU syndrome.
© 2022. The Author(s).
Conflict of interest statement
The authors declare that they have no competing interests.
Figures




Similar articles
-
Comprehensive assessment and progression of health status during neurorehabilitation in survivors of critical illness: a prospective cohort study.Ann Intensive Care. 2024 Nov 26;14(1):175. doi: 10.1186/s13613-024-01396-x. Ann Intensive Care. 2024. PMID: 39589665 Free PMC article.
-
Chronic Critical Illness and PICS Nutritional Strategies.J Clin Med. 2021 May 25;10(11):2294. doi: 10.3390/jcm10112294. J Clin Med. 2021. PMID: 34070395 Free PMC article. Review.
-
Post-intensive care syndrome: its pathophysiology, prevention, and future directions.Acute Med Surg. 2019 Apr 25;6(3):233-246. doi: 10.1002/ams2.415. eCollection 2019 Jul. Acute Med Surg. 2019. PMID: 31304024 Free PMC article. Review.
-
Improving management of ARDS: uniting acute management and long-term recovery.Crit Care. 2024 Feb 23;28(1):58. doi: 10.1186/s13054-024-04810-9. Crit Care. 2024. PMID: 38395902 Free PMC article. Review.
-
Prehabilitation to mitigate postintensive care syndrome in surgical patients: The rationale for a peri-critical illness pathway involving anaesthesiologists and intensive care physicians.Eur J Anaesthesiol. 2025 May 1;42(5):419-429. doi: 10.1097/EJA.0000000000002136. Epub 2025 Feb 14. Eur J Anaesthesiol. 2025. PMID: 39957494 Review.
Cited by
-
Sepsis and post-sepsis syndrome: a multisystem challenge requiring comprehensive care and management-a review.Front Med (Lausanne). 2025 Apr 8;12:1560737. doi: 10.3389/fmed.2025.1560737. eCollection 2025. Front Med (Lausanne). 2025. PMID: 40265185 Free PMC article. Review.
-
Depression or anxiety and long-term mortality among adult survivors of intensive care unit: a population-based cohort study.Crit Care. 2025 May 6;29(1):179. doi: 10.1186/s13054-025-05381-z. Crit Care. 2025. PMID: 40329374 Free PMC article.
-
Muscle weakness after critical illness: unravelling biological mechanisms and clinical hurdles.Crit Care. 2025 Jun 17;29(1):248. doi: 10.1186/s13054-025-05462-z. Crit Care. 2025. PMID: 40528196 Free PMC article. Review.
-
Supporting Post-ICU Recovery: A Narrative Review for General Practitioners.Diseases. 2025 Jun 11;13(6):183. doi: 10.3390/diseases13060183. Diseases. 2025. PMID: 40558594 Free PMC article. Review.
-
Intensive care unit-acquired weakness: Recent insights.J Intensive Med. 2023 Aug 30;4(1):73-80. doi: 10.1016/j.jointm.2023.07.002. eCollection 2024 Jan. J Intensive Med. 2023. PMID: 38263973 Free PMC article. Review.
References
-
- Hermans G, Van Mechelen H, Clerckx B, Vanhullebusch T, Mesotten D, Wilmer A, et al. Acute outcomes and 1-year mortality of intensive care unit-acquired weakness. A cohort study and propensity-matched analysis. Am J Respir Crit Care Med. 2014;190(4):410–20. doi: 10.1164/rccm.201312-2257OC. - DOI - PubMed
Publication types
LinkOut - more resources
Full Text Sources