The Advantages and Disadvantages of Methods Used to Control Liver Bleeding: A Review

Safety and Performance of Hemostatic Powders

Background

Hemorrhage, a sudden and severe leakage of blood due to the disruption of blood vessels, is one of the most common causes of death from injuries worldwide. Severe bleeding accounts for more than 35% of pre-hospital deaths and about 40% of deaths recorded within 24 hours of injury. One of the methods for achieving homeostasis is the use of hemostatic powders. This study compares the basic safety and performance of the most popular hemostatic powders.

Methods

Basic safety of commercially available products were evaluated using MTT, MEM elution assay, and endotoxin testing. The in vitro performance was evaluated using water absorption capacity, water absorption rate, and adhesion strength assays.

Results

4Seal, Starsil, and 4DryField extracts did not cause cytotoxicity in MTT and MEM elution assays. PerClot and SuperClot extracts demonstrated cytotoxic potential in MTT assay, while Arista extract was cytotoxic in both MEM elution and MTT assays. 4Seal has the lowest endotoxin contamination, followed by PerClot, 4DryField, SuperClot, Arista, and Starsil. 4Seal and Starsil showed significantly highest WAR among the tested samples, followed by 4DryField, Arista, PerClot, and SuperClot. Adhesion force is highest for 4Seal, followed by Starsil, PerClot, 4DryField Arista, and SuperClot.

Conclusion

4Seal is the most versatile in terms of safety and functional properties compared to 4DryField, Arista, PerClot, Starsil, and SuperClot.

Efficacy of a novel polyoxazoline-based hemostatic patch in liver and spleen surgery

BACKGROUND

A new hemostatic sealant based on a N-hydroxy-succinimide polyoxazoline (NHS-POx) polymer was evaluated to determine hemostatic efficacy and long-term wound healing and adverse effects in a large animal model of parenchymal organ surgical bleeds.

METHODS

Experiment 1 included 20 pigs that were treated with two NHS-POx patch prototypes [a gelatin fibrous carrier (GFC) with NHS-POx and an oxidized regenerated cellulose (ORC) with poly(lactic-co-glycolic acid)-NHS-POx:NU-POx (nucleophilically activated polyoxazoline)], a blank gelatin patch (GFC Blank), TachoSil^® and Veriset™ to stop moderate liver and spleen punch bleedings. After various survival periods (1-6 weeks), pigs were re-operated to evaluate patch degradation and parenchymal healing. During the re-operation, experiment 2 was performed: partial liver and spleen resections with severe bleeding, and hemostatic efficacy was evaluated under normal and heparinized conditions of the two previous prototypes and one additional NHS-POx patch. In the third experiment an improved NHS-POx patch (GATT-Patch; GFC-NHS-POx and added 20% as nucleophilically activated polyoxazoline; NU-POx) was compared with TachoSil^®, Veriset™ and GFC Blank on punch bleedings and partial liver and spleen resections for rapid (10s) hemostatic efficacy.

RESULTS

NHS-POx-based patches showed better (GFC-NHS-POx 83.1%, ORC-PLGA-NHS-POx: NU-POx 98.3%) hemostatic efficacy compared to TachoSil^® (25.0%) and GFC Blank (43.3%), and comparable efficacy with Veriset™ (96.7%) on moderate standardized punch bleedings on liver and spleen. All patches demonstrated gradual degradation over 6 weeks with a reduced local inflammation rate and an improved wound healing. For severe bleedings under non-heparinized conditions, hemostasis was achieved in 100% for Veriset™, 40% for TachoSil and 80-100% for the three NHS-POx prototypes; similar differences between patches remained for heparinized conditions. In experiment 3, GATT-Patch, Veriset™, TachoSil and GFC Blank reached hemostasis after 10s in 100%, 42.8%, 7.1% and 14.3%, respectively, and at 3 min in 100%, 100%, 14.3% and 35.7%, respectively, on all liver and spleen punctures and resections.

CONCLUSIONS

NHS-POx-based patches, and particularly the GATT-Patch, are fast in achieving effective hemostatic sealing on standardized moderate and severe bleedings without apparent long-term adverse events.

Effective sealing of biliary and pancreatic fistulas with a novel biodegradable polyurethane-based tissue sealant patch

BACKGROUND

To date, no approved sealants for the prevention of postoperative pancreatic fistulas (POPFs) or bile leakage are available. The aim of the study is to assess the feasibility of a new synthetic and biodegradable polyurethane-based sealant patch (PBSP) for hepato-pancreato-biliary (HPB) surgery.

METHODS

Benchmarking of the PBSP with commercially available products with a historical use in HPB surgery (Tachosil®, Hemopatch®, Surgicel® and Veriset®) was followed by performance testing in randomized controlled porcine animal studies. These studies focused on haemostasis as well as the prevention of POPFs and bile leakage.

RESULTS

The newly designed PBSP demonstrated the strongest adherence to liver tissue compared to Tachosil®, Hemopatch® and Veriset®. The new patch was the only patch with complete intra- and postoperative hemostasis (72 h after application) compared to Tachosil and Veriset in a porcine liver abrasion study on 12 animals. In addition, the new patch demonstrably prevents the development of POPFs. The rate of postoperative pancreatitis and clinically relevant POPFs was significantly lower compared to the control groups in a porcine pancreatic fistula model based on 14 animals (14-day follow-up). Furthermore, the incidence of biloma after 7 days, considered as significant bile leakage, was significantly lower in the new PBSP compared to the Veriset® group. The PBSP was as effective as suturing in a porcine bile leakage model (7-day follow-up).

CONCLUSION

The PBSP induces constant hemostasis in the context of liver resection and prevents pancreatic fistulas and bile leakage. The promising preclinical data implicate clinical trials for further evaluation of this newly developed patch.

Trauma laparotomy for the usual reasons, but for unusual causes

The impact of synchronous diseases or conditions on operative management of Trauma patients is not well established. In trauma patients, secondary diagnoses may complicate the treatment strategy and lead to changes in management and potentially outcomes. We present 5 unusual trauma cases and we discuss the difficulties and the outcomes we experienced in managing these patients.

Stereological Comparison of Imbibed Fibrinogen Gauze versus Simple Gauze in External Packing of Grade IV Liver Injury in Rats

Objective

To evaluate the effect of imbibed fibrinogen gauze on survival, bleeding and healing in liver trauma.

Methods

This animal experimental study was conducted on 20 adult male Sprague-Dawley rats; with a mean weight of 300±50 gram; divided into two groups. Grade IV injury was induced to the subjects' liver. Then, the bleeding site was packed with simple gauze in the control group, and imbibed fibrinogen gauze in the experimental group. All animals were re-evaluated for liver hemostasis 48 hours after the initial injury. Bleeding in the intra peritoneal cavity was measured using Tuberculosis Syringe in the first and second operations. Subjects were followed-up for 14 days. Eventually, the rats were sacrificed and their livers were sent to a lab for stereological assessment. Statistical comparisons were performed via Mann-Whitney U-test using SPSS. P-Values less than 0.05 were considered to be statistically significant.

Results

Half of the rats in the control group died, while all the rats in the imbibed fibrinogen gauze group survived after two weeks (p= 0.032). Bleeding in the imbibed fibrinogen gauze was significantly less than control group, 48 hours' post-surgery (p<0.001). According to the stereological results, granulation tissue in the imbibed fibrinogen gauze group were more than the control group (P= 0.032). Also, fibrosis in the imbibed fibrinogen gauze group were more than the control group (P= 0.014).

Conclusion

Our study indicated that imbibed fibrinogen gauze can potentially control liver bleeding and improve survival through increasing granulation tissue and fibrosis in injured liver.