Infections are the major issue with TPN (you're basically mainlining glucose). Keeping someone sedated for 2 weeks will significantly increased their risk of th

Infections are the major issue with TPN (you're basically mainlining glucose). Keeping someone sedated for 2 weeks will significantly increased their risk of thromboembolic disease (cooling them also increases the risk of thrombus). The sedation meds are going to be hard on their livers, kidneys, etc. The antibiotics necessary to prevent infections will also be hard on their livers, possibly kidneys. This would all require management by a critical care intensivist (anasthesiologist, pulmonologist, etc), who would escalate problems too ... where? You're taking astronauts and turning them into ICU patients. This seems incredibly bad.