Background: Survival after intensive care unit (ICU) admission has improved substantially over the past decades. However, many ICU survivors experience long-term physical, cognitive, and psychological impairments, collectively referred to as Post-Intensive Care Syndrome (PICS). The year following ICU discharge is characterized by high healthcare utilization, including frequent readmissions and out-patient visits. Despite this burden, structured follow-up after ICU discharge remains limited. Remote patient monitoring (RPM) using wearable technology may offer a way to support recovery, detect early deterioration, and personalize post-ICU care. At the Leiden University Medical Center (LUMC), RPM has already been implemented in several care pathways under the concept of “The Box.” The ICU Recover Box was developed as an adaptation of this concept specifically for ICU survivors.

Objective: The aim of my thesis is to identify possible improvements to the ICU Recover Box for implementation into clinical practice.

Methods: A mixed-methods approach was used within the second ICU Recover Box pilot study at the LUMC. First, an analysis was conducted on all included and excluded patients, to investigate how many of the eligible patients were inducted in the study, and what where reasons for exclusion. Second, semi-structured follow-up interviews were analyzed using thematic analysis to identify barriers, motivators, and suggested improvements from the patient perspective. Third, objective compliance data (wear-time and daily ECG measurements) collected from the wearable device were analyzed to evaluate adherence patterns over time.

Results: Between July and December 2025, 830 patients were admitted to the ICU, of whom 15 were actively participating in the study at the time of analysis. The most common reasons for exclusion of the study were short ICU stay, lack of mechanical ventilation, early ward discharge, cognitive impairment, and patient refusal. Several groups currently excluded in the research setting — such as patients discharged early or those declining research participation — may be reachable in future clinical implementation through alternative distribution strategies or integration into standard care.
Ease-of-use scores were generally high (mean 4–5 on a 5-point scale), though issues were reported regarding ECG measurement errors, cognitive burden related to daily tasks, skin irritation from the wristband, and login problems after app updates. Thematic analysis revealed that internal motivation (e.g., reassurance, insight into recovery) and external motivation (e.g., perceived oversight by healthcare professionals, caregiver involvement) were deemed to positively influence adherence. Barriers to adherence included discomfort of the wristband, technical errors, unclear instructions, and difficulty integrating ECG measurements into daily routine. Analysis of compliance rates showed relatively high wear-time during the first period of the study, followed by gradual decline over time. Daily ECG compliance, requiring a conscious action, was lower than passive wear-time compliance, indicating that active daily tasks related to home monitoring are more difficult to sustain than continuous passive monitoring.

Conclusion: Implementation of the ICU Recover Box into clinical practice requires improvements which can be categorized in three main levels. At the level of the physical devices used in the ICU Recover Box, implementation depends on reducing user burden and ensuring accessibility. At the level of the app and accompanying service, it must function as a personalized recovery tool with clear and supportive communication rather than merely a passive data collection platform. At the system and organizational level, sustainable adoption requires structural embedding within clinical workflows, multidisciplinary alignment across departments involved in a patient’s care, and feasible distribution methods for the Box. Passive monitoring appears more sustainable than daily active measurements. Implementation success depends not on isolated improvements, but on the refinement across the board. Continuous alignment between technological possibilities and the clinical realities of ICU survivorship is essential to keep ensuring both feasibility and relevance of the ICU Recover Box.