Influence of Deep Sedation in Intensive Care Medicine Memories of Critical COVID-19 Survivors

Introduction: Critical care survivors sustain a variety of sequelae after intensive care medicine (ICM) admission, and the Coronavirus Disease 2019 (COVID-19) pandemic has added further challenges. Specifically, ICM memories play a significant role, and delusional memories are associated with poor outcomes post-discharge including a delayed return to work and sleep problems. Deep sedation has been associated with a greater risk of perceiving delusional memories, bringing a move toward lighter sedation. However, there are limited reports on post-ICM memories in COVID-19, and influence of deep sedation has not been fully defined. Therefore, we aimed to evaluate ICM-memory recall in COVID-19 survivors and their relation with deep sedation. Materials/Methods: Adult COVID-19 ICM survivors admitted to a Portuguese University Hospital between October 2020 and April 2021 (second/third “waves”) were evaluated 1 to 2 months post-discharge using “ICU Memory Tool,” to assess real, emotional, and delusional memories. Results: The study included 132 patients (67% male; median age = 62 years, Acute Physiology and Chronic Health Evaluation [APACHE]-II = 15, Simplified Acute Physiology Score [SAPS]-II = 35, ICM stay = 9 days). Approximately 42% received deep sedation (median duration = 19 days). Most participants reported real (87%) and emotional (77%) recalls, with lesser delusional memories (36.4%). Deeply sedated patients reported significantly fewer real memories (78.6% vs 93.4%, P = .012) and increased delusional memories (60.7% vs 18.4%, P < .001), with no difference in emotional memories (75% vs 80.4%, P = .468). In multivariate analysis, deep sedation had a significant, independent association with delusional memories, increasing their likelihood by a factor of approximately 6 (OR = 6.274; 95% confidence interval = 1.165-33.773, P = .032), without influencing real (P = .545) or emotional (P = .133) memories. Conclusions: This study contributes to a better understanding of the potential adverse effects of deep sedation on ICM memories in critical COVID-19 survivors, indicating a significant, independent association with the incidence of delusional recalls. Although further studies are needed to support these findings, they suggest that strategies targeted to minimize sedation should be favored, aiming to improve long-term recovery.