BackgroundClinical tissue adhesives remain some critical drawbacks for managing emergency injuries, such as inadequate adhesive strength and insufficient anti-infection ability. Herein, a novel, self-healing, and antibacterial carboxymethyl chitosan/polyaldehyde dextran (CMCS/PD) hydrogel is designed as the first-aid tissue adhesive for effective trauma emergency management.MethodsWe examined the gel-forming time, porosity, self-healing, antibacterial properties, cytotoxicity, adhesive strength, and hemocompatibility. Liver hemorrhage, tail severance, and skin wound infection models of rats are constructed in vivo, respectively.ResultsResults demonstrate that the CMCS/PD hydrogel has the rapid gel-forming (~ 5 s), good self-healing, and effective antibacterial abilities, and could adhere to tissue firmly (adhesive strength of ~ 10 kPa and burst pressure of 327.5 mmHg) with excellent hemocompatibility and cytocompatibility. This suggests the great prospect of CMCS/PD hydrogel in acting as a first-aid tissue adhesive for trauma emergency management. The CMCS/PD hydrogel is observed to not only achieve rapid hemostasis for curing liver hemorrhage and tail severance in comparison to commercial hemostatic gel (Surgiflo ®) but also exhibit superior anti-infection for treating acute skin trauma compared with clinical disinfectant gel (Prontosan ®).ConclusionsOverall, the CMCS/PD hydrogel offers a promising candidate for first-aid tissue adhesives to manage the trauma emergency. Because of the rapid gel-forming time, it could also be applied as a liquid first-aid bandage for mini-invasive surgical treatment.Graphical AbstractSupplementary InformationThe online version contains supplementary material available at 10.1186/s40824-023-00392-9.