Hydrogels in Airway Devices and Tracheal Repair: Clinical Requirements, Patient‐Specific Manufacturing, and Translational Testing

Airway stents can rapidly restore ventilation in central airway obstruction, but complications after placement remain common. Migration, mucus retention, infection, granulation, fracture, and difficult removal often reflect a mismatch between the device and the airway environment. This review examines how hydrogels may contribute to airway devices and tracheal repair, with emphasis on clinically relevant design and testing criteria. Hydrogels provide a water-rich interface and allow control of mechanics, degradation, and local delivery. Softness alone, however, cannot maintain airway patency. A useful hydrogel-enabled device must keep the lumen open during breathing and coughing without excessive wall pressure, while also preserving mucus transport. The review covers hydrogel classes and manufacturing routes relevant to patient-specific devices. 4D shape programming is considered an early concept rather than a proven airway-stent strategy. Direct evidence for intraluminal stents still comes mainly from printed degradable elastomers, whereas most hydrogel studies concern tracheal repair or surface biology. Rabbit studies are informative but remain limited by small cohorts and short follow-up. A structural frame with a hydrogel surface therefore appears to be the most realistic near-term route. Translation will require testing of the final sterilized device under cyclic loading and airway-like conditions.