A novel injectable thermo‐sensitive binary hydrogels system for facilitating endoscopic submucosal dissection procedure

Abstract

Background and aims Making an optimal and lasting submucosal cushion is critical for endoscopic submucosal dissection. The thermo-sensitive binary hydrogels system composed of poloxamer 407 and poloxamer 188 might be an excellent submucosal injection solution considering the unique feature that it remains liquid at room temperature and becomes gelatinous after being injected in the submucosa of the digestive tract. The present study focuses on preparing the thermo-sensitive binary hydrogels system and testing its capacity in mucosal lifting and its role in the endoscopic submucosal dissection procedure. Methods Various concentrations of poloxamer 407 and poloxamer 188 were added to normal saline. The gelation temperature viscosity of the thermo-sensitive binary hydrogels system was measured to choose the best formula. The thermo-sensitive binary hydrogels system and normal saline were first compared in extracted porcine stomach. For in vivo study, the thermo-sensitive binary hydrogels system and normal saline were compared for facilitating the endoscopic submucosal dissection procedure. Results Among the 46 kinds of thermo-sensitive binary hydrogels system, gelation temperatures of the thermo-sensitive binary hydrogels system I (poloxamer 407/poloxamer 188, 17%/0.5%, w/w) and the thermo-sensitive binary hydrogels system II (poloxamer 407/poloxamer 188, 18%/2%, w/w) were among the ideal range of gelation temperature. The injecting pressure in vitro study of thermo-sensitive binary hydrogels system II was significantly higher than that of thermo-sensitive binary hydrogels system I and normal saline ( p < 0.001). Sixteen gastric endoscopic submucosal dissection procedures were performed in a porcine model. The initial volume of normal saline injection (13.88 ± 3.91 ml vs 5.88 ± 3.44 ml, p = 0.001) was significantly larger than the thermo-sensitive binary hydrogels system group. The postoperative wound showed a significant difference in the two groups ( p = 0.023) indicating that the thermo-sensitive binary hydrogels system can create a cleaner wound. Conclusions Considering the gelation temperature, viscosity, injection pressure, and the height of the mucosal elevation, the thermo-sensitive binary hydrogels system I was the better submucosal injection solution.

Efficacy and safety of a thermosensitive hydrogel for endoscopic submucosal dissection: An in vivo swine study

“…The outcomes of this study correspond with those of an earlier study that reported the binary hydrogel system to be significantly superior to NS in fluid volume and wound healing [ 23 ]. Data from experimental animals showed that the thermosensitive binary hydrogel system (TBHS), comprising poloxamer 407 and 188, required less total injected volume than NS (22.13 mL vs. 6.63 mL, p<0.001).…”

“…Another explanation can be attributed to the endoscopists ability itself. It has been reported that dissection speed commonly does not vary when endoscopists, who have obtained proficiency in ESD, are involved [ 23 ]. Dissection speed was, therefore, broken down into two volume parameters, fluid power and fluid consumption rate, of which the values varied depending on the types of solutions used.…”

Injectable Self-Healing Adhesive pH-Responsive Hydrogels Accelerate Gastric Hemostasis and Wound Healing

“…These endoscopic techniques possess several advantages, including being less invasive than surgery, having a curative resection effect and retaining the physiological gastrointestinal structure. Although endoscopic treatment techniques and instruments have been improving, EMR and ESD of the mucosal layer are associated with intra- and postprocedural complications such as bleeding and perforation [ 6 , 7 ]. Additionally, postprocedure bleeding can develop as late as 2 weeks after treatment [ 8 ].…”

Injectable Thermogel Generated by the “Block Blend” Strategy as a Biomaterial for Endoscopic Submucosal Dissection

“…As a dye, 1 wt % indigo carmine solution was added. The upper third part of the porcine stomach was employed owing to its thickness and similar histology to that of the human stomach. , The stomach was cut into a 5 × 5 cm 2 square and stretched flat on a corkboard with pins. A 20 mL syringe connected with a 23-gauge injection needle was applied to inject about 5 mL of each solution into the submucosa layer to obtain an elevation of about 10 mm.…”