Arterial embolization for hemorrhage caused by hepatic arterial injury

Intravascular and intraparenchymatous hepatic segmentary sclerosis

PURPOSE

To evaluate the morphological effects of injected sclerosing agents into the liver.

METHODS

This study was performed on twenty dogs, distributed into five groups: Group 1 (n = 5) - control, Group 2 (n = 5) - injection of 50% glucose solution inside hepatic parenchyma and animals followed during seven days, Group 3 (n = 10) - injection of ethanol inside hepatic parenchyma and animals distribution into two subgroups Subgroup 3A (n = 5) - followed during 24 hours and subgroup 3B (n = 5) - followed during seven days (group 3B), Group 4 (n = 5) - ethanol injection inside left portal vein branch and followed during 24 hours. Livers were macroscopically evaluated, submitted to hepatic arteriography and portography, then histology.

RESULTS

All animals in Group 4 died within 23 hours due to diffuse hepatic necrosis. The animals of groups 2 and 3 had a satisfactory evolution. Fibrosis formed in the segment reached by the sclerosant solution and interruption of the contrast flow injected into the portal system.

CONCLUSION

Intrahepatic parenchymal ethanol injection is well tolerated and causes sclerosis restricted to a specific segment; however, intraportal ethanol injection causes massive hepatic necrosis and can lead to death.

Non-operative management of hepatic trauma and the interventional radiology: an update review

The growing trend to manage hepatic injuries nonoperatively has been increasing demand for advanced endovascular interventions. This brings up the necessity for general and trauma surgeons to update their knowledge in such matter. Effective treatment mandates a multispecialty team effort that is usually led by the trauma surgeon and includes vascular surgery, orthopedics, and, increasingly, interventional radiology. The focus on hemorrhage control and the angiographer's unique access to vascular structures gives interventional radiology (IR) an important and increasingly recognized role in the treatment of patients with hemodynamic instability. Our aim is to review the basic concepts of IR primarily in hepatic trauma and secondarily in some other special situations. A liver vascular anatomy review is also needed for better understanding the roles of IR. As a final point we propose a guideline for the operative/nonoperative management of traumatic hepatic injuries. The benefit of multidisciplinary approach (TAE) appears to be a powerful weapon in the medical arsenal against the high mortality of injured trauma liver patients.

Delivery of water-soluble drugs using acoustically triggered perfluorocarbon double emulsions

PURPOSE

Ultrasound can be used to release a therapeutic payload encapsulated within a perfluorocarbon (PFC) emulsion via acoustic droplet vaporization (ADV), a process whereby the PFC phase is vaporized and the agent is released. ADV-generated microbubbles have been previously used to selectively occlude blood vessels in vivo. The coupling of ADV-generated drug delivery and occlusion has therapeutically synergistic potentials.

METHODS

Micron-sized, water-in-PFC-in-water (W(1)/PFC/W(2)) emulsions were prepared in a two-step process using perfluoropentane (PFP) or perfluorohexane (PFH) as the PFC phase. Fluorescein or thrombin was contained in the W(1) phase.

RESULTS

Double emulsions containing fluorescein in the W(1) phase displayed a 5.7±1.4-fold and 8.2±1.3-fold increase in fluorescein mass flux, as measured using a Franz diffusion cell, after ADV for the PFP and PFH emulsions, respectively. Thrombin was stably retained in four out of five double emulsions. For three out of five formulations tested, the clotting time of whole blood decreased, in a statistically significant manner (p < 0.01), when incubated with thrombin-loaded emulsions exposed to ultrasound compared to emulsions not exposed to ultrasound.

CONCLUSIONS

ADV can be used to spatially and temporally control the delivery of water-soluble compounds formulated in PFC double emulsions. Thrombin release could extend the duration of ADV-generated, microbubble occlusions.