Timing of Thickened Liquid Intake After Tongue and Floor-of-Mouth Tumour Reconstruction: A Randomised Controlled Trial.

[OBJECTIVE] This study aimed to determine the optimal timing and viscosity of thickened liquid intake for patients undergoing tongue and floor-of-mouth tumour resection with reconstruction, using VFSS to reduce nasogastric tube dependence, improve swallowing function, and the quality of life.

[METHODS] This randomised controlled trial was conducted at a dental specialty hospital from September 2023 to November 2024. Forty-three patients who underwent free flap reconstruction for tongue and floor-of-mouth tumours were randomly divided into control (n = 22) and intervention groups (n = 21). Both received swallowing training, but the intervention group followed a structured oral intake protocol with thickened liquids. After tracheostomy removal, patients received 5 mL of medium-viscosity liquid. If no aspiration occurred, VFSS was performed using 5 mL each of medium-, low- and high-viscosity liquids. The liquid with the lowest PAS score was selected for oral intake. Nasogastric tubes were removed upon safe consumption of 200 mL within 20 min. Outcomes included tube duration, swallowing function, weight loss and quality of life.

[RESULTS] VFSS revealed increasing penetration risk with viscosity: 52.4% for low-viscosity, 23.8% for medium-viscosity and 19.0% for high-viscosity liquids. Low-viscosity liquids exhibited an aspiration rate of 14.3%, whereas no aspiration was observed with medium- or high-viscosity liquids. The intervention group had shorter nasogastric tube duration (9.2 vs. 15.6 days, p < 0.05), better swallowing function, less weight loss and higher quality of life (p < 0.05).

[CONCLUSION] A structured thickened liquid diet protocol safely reduces nasogastric tube dependence, enhances swallowing function and quality of life postoperatively.