Hepatic Resection (Lobectomy, Segmentectomy, Wedge)

Low CVP during transection - the cut hepatic veins are valveless and continuous with the right atrium, so central venous pressure drives blood out of the raw surface. Keep it low until the specimen is out, and have the surgeon call the start and end of transection.

Staying deliberately dry - restrict maintenance crystalloid to roughly 1 mL/kg/h and withhold colloid or product not replacing a real deficit. Blood loss during transection is the single strongest predictor of morbidity.

Vasopressor, not fluid - a dry patient will drop the MAP, and volume given reflexively refills the veins being cut. Support the pressure with a norepinephrine infusion instead; low CVP plus unsupported hypotension is how these patients reach the ICU with acute kidney injury.

Venous air embolism - open hepatic veins at subatmospheric pressure entrain air, and the risk rises the lower the CVP and the higher the liver sits. Keep the patient flat or slightly head-down during transection rather than in reverse Trendelenburg, and watch end-tidal CO2.

Air until proven otherwise - treat a sudden end-tidal CO2 drop with hypotension as entrained air: tell the surgeon to flood the field, stop nitrous if it is running, and give volume and pressor.

Pringle maneuver and reperfusion - cross-clamping the hepatoduodenal ligament costs about a quarter of venous return and raises SVR, so cardiac output falls with a preserved MAP. Call clamp and release times out loud, and have vasopressor and calcium ready before release returns an acidotic, potassium-rich bolus.

Access for sudden loss - intrahepatic branches can empty a patient in minutes with no warning from the field. Two large-bore IVs and a rapid infuser, an arterial line for pressure plus gases, lactate and calcium, and a central line for CVP trending and pressor. Confirm crossmatched blood is in the building.

Coagulopathy in the cirrhotic liver - hepatocellular carcinoma usually sits on a cirrhotic liver: reduced factor synthesis, thrombocytopenia from hypersplenism, hemostasis rebalanced rather than anticoagulated. INR and platelet count will not tell you whether this cut surface clots, so use viscoelastic testing to direct components.

Transfusion and the CVP - follow your institution's massive transfusion protocol for ratios and triggers, and remember that empiric plasma raises the pressure you are working to keep down.

Drug handling with a shrinking liver - you are removing metabolic mass mid-case, and hepatic blood flow falls with every Pringle. Favor cisatracurium, cleared by Hofmann elimination, and remifentanil, cleared by plasma esterases; titrate hypnotic to a processed EEG and assume late drugs outlast the label.

Glucose after transection - the liver is the glycogen store, and a large resection in a cirrhotic patient with limited reserve can drop the glucose once the specimen is out. Check hourly from transection onward and again in PACU.

Temperature as hemostasis - a long case with an open abdomen and large-volume resuscitation runs cold, and hypothermia worsens the coagulopathy on a raw liver surface. Forced-air warming above and below the field, an in-line fluid warmer, and warm irrigation.

The epidural question - the subcostal incision is painful, but INR commonly rises over the first postoperative days as synthetic function dips, creating a catheter-removal problem that did not exist at insertion. Weigh TAP or rectus sheath catheters, intrathecal morphine, or multimodal IV, and time any catheter against current ASRA guidance.

The liver takes roughly a quarter of cardiac output through two inflows - the hepatic artery and the portal vein - and drains through valveless hepatic veins straight into the intrahepatic inferior vena cava. That drainage anatomy is what makes the operation bleed: once the parenchyma is cut, open hepatic venous radicles sit in direct pressure continuity with the right atrium, so back-bleeding tracks whatever the central venous pressure happens to be. Inflow can be clamped; outflow cannot, short of total vascular exclusion. Most resections are done for hepatocellular carcinoma on a background of cirrhosis or for colorectal metastases in an otherwise normal liver, and that distinction drives everything downstream - synthetic reserve, portal pressure, platelet count, and how much parenchyma can be taken before the remnant fails.

Positioning and access - Supine, upper midline incision extended to a right subcostal limb, with a self-retaining costal-margin retractor lifting the rib cage cephalad for exposure of the hepatic veins and suprahepatic cava.

Mobilization - The falciform, triangular, and coronary ligaments are divided and the lobe is rolled medially off the retroperitoneum and cava, with short hepatic veins ligated as they are encountered.

Intraoperative ultrasound - The surgeon scans the whole liver to map the lesion against the intrahepatic portal and hepatic venous anatomy, confirm margins, and pick up lesions imaging missed. The plan can change on the table from anatomic lobectomy to a nonanatomic wedge.

Inflow control - For anatomic resection the porta hepatis is dissected and the hepatic arterial branch, portal branch, and bile duct to the target lobe are ligated, producing a visible line of demarcation. A Pringle tape is placed around the hepatoduodenal ligament for intermittent inflow occlusion whether or not it is used.

Parenchymal transection - The capsule is scored and the parenchyma is divided with an ultrasonic dissector, water-jet, or stapler, skeletonizing vessels and ducts for clipping. This is the bleeding step and the one the anesthetic is built around.

Outflow division - The main hepatic vein to the resected segment is stapled or oversewn, either extrahepatically before transection or from within the parenchyma at the end.

Hemostasis and bile leak check - Argon beam or topical sealant to the raw surface, then inspection for bile staining. Subhepatic drains are placed at the surgeon's discretion.

Laparoscopic and robotic variants - Increasingly used for left lateral segmentectomy, peripheral wedges, and in experienced hands major right hepatectomy, with pneumoperitoneum providing some tamponade of the cut surface.

Extubation is the norm for a straightforward segmentectomy or wedge, but keep the ICU option open for a major right hepatectomy that took a lot of product, ran cold, or ended acidotic - the remnant may not clear lactate or drugs for a day or two, and post-hepatectomy liver failure declares itself with encephalopathy and a climbing bilirubin rather than anything visible in the OR.

For the laparoscopic or robotic approach, pneumoperitoneum tamponades the cut surface but also raises the consequence of any air entrained through an open hepatic vein, so the ETCO2 trace deserves the same attention it gets open. Cell salvage is generally avoided when the indication is malignancy, which removes a rescue option and makes the low-CVP technique and early blood availability matter more, not less.

Ask specifically whether the patient has had preoperative portal vein embolization or chemotherapy for colorectal metastases. Both change what the remnant can do, and prolonged oxaliplatin or irinotecan exposure leaves a liver that bleeds and recovers worse than its size suggests.