Implications of the consciousness state on decannulation in patients with a prolonged Disorder of Consciousness

Objective to prospectively investigate the evolution of the consciousness state and the cannula-weaning progression in patients with prolonged Disorders of Consciousness (pDoC). Design non-concurrent cohort study Setting rehabilitation unit of the Fondazione Don Gnocchi, Florence Participants adult patients, with a pDoC following a sABI admitted between 06.2020 and 09.2022 Interventions not applicable Main outcome measures consciousness state was assessed by repeated Coma Recovery Scale-Revised (CRS-R) administration at admission, and weekly afterwards. The dates of the first improvement of consciousness state and the achievement of decannulation were recorded. Decannulation followed an internal protocol of multi-professional rehabilitation. Results 144 patients were included: age: 69 years, 64 (44.4%) with hemorrhagic etiology, time post-onset: 40 days, CRS-R at admission: 9, median length of stay: 90 days. Seventy-three (50.7%) patients were decannulated. They showed a significantly higher CRS-R (p<0.001) and states of consciousness (p<0.001) at admission, at the first improvement of the consciousness state (p=0.003), and discharge (p<0.001), a lower severity in the Cumulative Illness Rating Scale at admission (p=0.01), and a lower rate of pulmonary infections with recurrence (p=0.021), compared to non-decannulated patients. Almost all decannulated patients (97.3%) improved their consciousness before decannulation. Consciousness states at decannulation were: Unresponsive wakefulness Syndrome: 0 (0%), Minimally conscious state (MCS) minus: 4 (5.5%), MCS plus: 7 (9.6%), Emergence from MCS: 62 (84.9%). Kaplan-Meier analysis showed a significant divergence between the curves with a higher probability of decannulation in patients who improved consciousness (p<0.001). Conclusion This study showed that the presence of signs of consciousness, even subtle, is a necessary condition for decannulation, suggesting that consciousness may influence some of the components implied in the decannulation process.