Participants receive standard post-ICU follow-up care according to hospital protocols . This includes routine health assessments and general rehabilitation guidance at designated intervals (discharge, 7 days, 1/3/6 months post-discharge). No structured PICS management program or AI technology is provided.

Participants receive an evidence-based, optimized PICS management program developed using the Health Promotion Model (HPM). This includes personalized rehabilitation plans, psychological support, and education tailored to PICS symptoms. Interventions are delivered by clinical staff at discharge, 7 days, and 1/3/6 months post-discharge. No AI/LLM technology is used.

Participants receive the same optimized PICS program as Group B, enhanced with Large Language Models (LLMs). Key components:

Personalized AI-generated plans: ChatGPT-4 synthesizes patient data (baseline + follow-ups) to create monthly rehabilitation plans, reviewed by a multidisciplinary expert team.

LLM access: Installation of "Kimi Smart Assistant" for daily health queries. Safety protocols: Patients must validate LLM advice with nurses via WeChat before use .

Phased intervention:

Pre-discharge: LLM training + baseline plan generation.

1 month: Plan updates based on new data. 3/6 months: Plan updates + semi-structured interviews about LLM experience.

Participants receive standard post-ICU follow-up care according to hospital protocols . This includes routine health assessments and general rehabilitation guidance at designated intervals (discharge, 1/3/6 months post-discharge). No structured PICS management program or AI technology is provided.

- Total score of the Chinese Version of the Post-Intensive Care Syndrome Questionnaire (PICSQ).

Domains: Physical function (6 items), cognitive impairment (6 items), psychological symptoms (6 items).

Scoring: 18 items × 0-3 points = 0-54 total; higher scores = worse symptoms.

• Total score of the Pittsburgh Sleep Quality Index (PSQI). Scoring: 7 components × 0-3 points = 0-21 total; higher scores = poorer sleep.
• Recall experiences measured by the Chinese ICU Memory Tool (ICUMT). Format: 14-item mixed open/closed questions about ICU admission, treatment, and discharge memories.
• Anxiety: GAD-7 score (0-21; higher = worse anxiety). Depression: PHQ-9 score (0-27; higher = worse depression).

- Total score of the Adults Health Self-Management Ability Rating Scale (AHSMSRS).

Scoring: 38 items × 1-3 points = 38-114 total; higher scores = poorer self-management.