Surgical treatment of liver injury with microwave tissue coagulation: an experimental study.
OBJECTIVE
The purpose of this study was to examine whether microwave tissue coagulation (MTC) therapy is capable of stopping bleeding from severe liver injury in pigs.


METHODS
Ten pigs (38 +/- 4 kg) underwent a 30-mL/kg isovolemic exchange transfusion with 3% low-molecular-weight dextran to produce dilutional coagulopathy, and then a through-and-through laceration injury measuring approximately 8 cm in length was induced in the right hepatic lobe. Immediately after inflicting the injury, the animals were randomly divided into two groups: Group A (n = 5, MTC was repeated along the liver laceration at intervals of 2.0 cm with manual compression) or Group B (n = 5, the injured lobe was manually compressed without MTC therapy for 1 minute). All animals received lactated Ringer's solution to maintain the mean arterial pressure at 75 mm Hg for 1 hour after the abdominal closure. The intraperitoneal blood loss, mean arterial pressure, volume of lactated Ringer's solution, and hematologic variables were compared between the groups. For further laboratory evaluation, three additional experimental animals were treated with the MTC therapy after inflicting the injury and then were allowed to survive for 14 days.


RESULTS
Mean arterial pressure declined from a mean value of 88 +/- 10 mm Hg (range, 75-107 mm Hg) to 62 +/- 3 mm Hg (range, 50-75 mm Hg) after the induction of liver injury. The total blood loss in Group A was 192 +/- 58 g (range, 120-250 g), which was lower (p < 0.01) than that of 448 +/- 138 g (range, 260-650 g) in Group B. The resuscitation fluid volume of Group A animals was 304 +/- 204 mL (range, 100-600 mL), which was smaller (p < 0.01) than that of 1,320 +/- 654 mL (range, 900-2,250 mL) in Group B. At 14 days, all three animals that were treated in the additional study were found to be in good health. Their necropsies showed no evidence of an intrahepatic abscess, hematoma, or biloma.


CONCLUSIONS
MTC therapy was thus found to provide simple, rapid, and definitive hemorrhage control in cases of severe liver injury without the need for reoperation.
Takasu
Akira
A
Department of Traumatology and Critical Care Medicine, National Defense Medical College, Saitama, Japan. atakasu@me.ndmc.ac.jp
Norio
Hirofumi
H
Sakamoto
Toshihisa
T
Okada
Yoshiaki
Y
D000818:Animals; D001794:Blood Pressure; D003911:Dextrans / Q000627:therapeutic use; D004195:Disease Models, Animal; D004564:Electrocoagulation / Q000295:instrumentation / Q000379:methods*; D005078:Exchange Transfusion, Whole Blood / Q000379:methods; D005440:Fluid Therapy / Q000379:methods; D006400:Hematocrit; D006438:Hemodilution / Q000379:methods; D006470:Hemorrhage / Q000209:etiology / Q000517:prevention & control; D006488:Hemostasis, Surgical / Q000295:instrumentation / Q000379:methods*; D008099:Liver / Q000293:injuries / Q000601:surgery; D008872:Microwaves / Q000627:therapeutic use*; D008991:Monitoring, Physiologic / Q000379:methods; D010952:Plasma Substitutes / Q000627:therapeutic use; D011897:Random Allocation; D012151:Resuscitation / Q000379:methods; D015996:Survival Rate; D013552:Swine; D013997:Time Factors; D016896:Treatment Outcome; D014949:Wounds, Nonpenetrating / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000601:surgery; D014950:Wounds, Penetrating / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*
D003911:Dextrans; D010952:Plasma Substitutes