OBJECTIVES: Medical complications occur frequently in MCS and influence advance medical decision-making. This study aimed to report on medical complications and advance medical decision-making in a nationwide group of MCS patients. METHODS: In this descriptive cross-sectional study, clinical and advance medical decision-making characteristics were collected in a survey, completed by the treating physician. RESULTS: The MCS population consisted of 32 patients: 65.6% traumatic etiology, 68.8% male. Patients had a median of five complications: hypertonia/spasticity (81.3%) and pneumonia (50.0%) occurred most frequently. Most patients had curative goals: three patients had a fully curative treatment scenarios, 29 a curative scenario with ≥ 1 treatment restrictions, two a palliative and two a symptomatic scenario. Conversations about advance medical decision-making were complicated by disputes with next of kin, inability to evaluate medical treatment because of medical instability, next of kin not being ready to discuss medical treatment, or a treatment scenario explicitly based on requests of next of kin. CONCLUSION: Medical complications are common in MCS patients and advance medical decision making was complicated. This legitimates realization of specialized care across acute, post-acute and long-term care. Further longitudinal research into advance medical decision-making is recommended.