Effectiveness and safety of CEUS-guided haemostatic injection for blunt splenic trauma: an animal experiment

The aim of this study was to investigate whether complications occur after haemostatic agents are injected into blunt splenic injuries. After undergoing ultrasound (US), contrast-enhanced US (CEUS) and contrast-enhanced computed tomography (CECT) examinations, dogs with grade III-IV injury received the minimally invasive therapy. After treatment, CEUS was performed to observe changes in the regions treated. In the immediate group, dogs underwent laparotomy 30 min after treatment to observe the haemostatic effect. In the survival group, animals underwent CEUS and CECT examinations to observe the short-term healing outcome and complications at 3, 7, 14, and 21 days after the injection. After undergoing CEUS and CECT examinations, 12 dogs with grade III-IV injury received the minimally invasive therapy. Before injection, CEUS examinations showed anechoic and/or hypoechoic perfusion defects and active bleeding at the injury sites, and CECT showed traumatic lesions as low-density regions without enhancement. After treatment, CEUS demonstrated the disappearance of active bleeding, and hyperechoic spots emerged at the injury sites. Uneven density regions were displayed on CECT. Treated areas were covered by blood clots and glue membrane in the immediate-group animals. Three weeks later, CEUS showed a decrease of hyperechoic spots in the survival group, and the splenic parenchyma enhanced uniformly on CECT. Laparotomy showed that the greater omentum had moved upwards and partly covered the wound in four animals, and the injury sites had completely healed. Histopathological examination showed that fibrous connective tissue covered the splenic capsule and that the haemostatic glue had degraded. No complication occurred, such as delayed splenic haemorrhage, splenic abscesses, splenic pseudoaneurysms, intestinal obstruction or intestinal adhesions. CEUS-guided haemostatic injection is not only effective in stopping active bleeding immediately, but it is also safe in that no complications occurred during the 3 weeks of follow-up. This study indicates that CEUS-guided percutaneous injection may provide a safe, feasible and effective therapy for blunt splenic trauma.