To begin, subcutaneously inject one milliliter of lactated Ringer's solution mixed with 5%glucose into the anesthetized mice. Use small animal clippers to shave a two-centimeter area on the abdominal region of the mouse. Then, make a midline incision with a surgical scalpel.
Open the incision with a pair of surgical scissors. Use an abdominal retractor to expand the incision, while facilitating the gentle traction of the duodenum and a section of the small intestine with sterile, moist cotton swabs. Cover the structures with a pre-prepared sterile cotton swab to expose the hepatic segment of the portal vein.
For portal vein ligation, peel off the peritoneum and intestinal tract. Encircle the main portal vein's branches with slow, deliberate, forward pushing and spreading movements. Identify the right posterior branch, the combined left lateral and median branches, and the caudate branch.
Next, to dissect the right posterior branch, locate its prominent, visible branch when traversing the hepatic hilum via the main portal vein. Use moistened cotton balls as a fulling agent to separate the liver's middle lobe from the right posterior lobe. Dissect along the Glisson's capsule.
Pull a 1.5-centimeter long silk tie around the portal vein branches. Then, use an 8-0 silk suture to ligate the right posterior branch. For the dissection of the left lateral and median branches, first, dissect any potential interstice between the left lateral lobe and the caudate lobe.
Then, introduce a pair of micro forceps into the entrance created. When resistance is felt, adjust the micro forceps slightly to move through the surface of the Glisson's capsule of the right medial lobe. Tie an 8-0 silk suture around the portal vein of the left lateral and median branches.
Successful ligation can be observed by the ischemic demarcation within the liver's middle lobe with pallor on the left lobe. Next, dissect the caudal lobe. Fill the potential space between the main portal vein and the caudate lobe with a cotton swab.
Peel away the peritoneum of the caudate lobes to visualize the portal vein branches of the lobe. Ligate the caudate branch with a stitch-up suture, ensuring that the needle path adequately wraps the caudate branch. To transect the liver, use an electrocautery pen to create a 0.5-millimeter pre-cut line along the demarcation line in the middle liver lobe.
With a pair of micro forceps and the electrocautery pen, cut the liver tissue. Swab the bleeding with cotton. Remove the gallbladder at the end, as it provides a good pulling point through transection.
Use a cotton swab to apply controlled pressure for hemostasis. Once transection and cholecystectomy are complete, carefully place the small bowel back into the abdominal cavity. Close the peritoneum and the abdominal wall with 6-0 absorbable sutures.
Disinfect the skin's surface, and then subcutaneously inject fentanyl and meloxicam mixed with saline to alleviate postoperative pain. Place the mouse on a thermostatic pad to facilitate awakening. Transfer them into individual cages when they regain consciousness.
Subcutaneously inject medetomidine, continuing for 24 hours postoperatively. Mice that were subjected to ALPPS showed a higher proclivity to cellular proliferation. Inflammatory markers of the ALPPS mice, specifically interleukin-6, were higher than those observed in the PVL group.
