Liver Transections

July 5, 2024

LOW CVP ANESTHESIA

• why to do it?
  • if we are doing a liver surgery, we do pringles, but hepatic veins are not taken care of ; therefore there is back bleed
  • to prevent the back bleed, we rely on CVP.
• how to decrease CVP?
  1. restricted fluid policy
  2. low tidal volume anesthesia
  3. can use vasodilators = nitrates etc
  4. reverse trendelenberg position = head up
  5. Surgically = Clamp infrahepatic IVC
  6. Prehepatic phase:
     • .-Isofluorane, fentanyl, nitroglycerin
     • -Permissive hypotension
     • -Permissive oliguria
• Disdvantages of LOW CVP anesthesia:
  • Air Embolism = check with ETCO2 = if it is low then air embolism
  • Venous return to heart is low = to maintain we start on vasopressors to maintain MAP
  • Renal Failure = in pt’s with borderline renal failure cases
• How to minimise Blood loss ?
  • Prevent Hypothermia
    • Keep pt covered, OT temp = 21-24 deg C ; Fluid warmers; Warming mattress; Gamgee wrapping
    • Keep CVP below 5mm hg
      • 15 deg Reverse trendelenberg position, Restrict fluids, Epidural infusion, Low tidal volume Ventilation, Pharmacology ( Isoflurane, NTG, Esmolol, Diuretics)
      • Infrahepatic IVC control
      • Cx= Renal dysfunction, air embolism
    • Tranexamic acid, Terlipressin
    • Restrictive Transfusion Policy

Major Liver Resections = Makuchi Criteria

• Ascites is Uncontrolled/ Bilirubin is >2 = No liver resection is done
• If controlled we look for Total Bilirubin and follow with flowchart

• If Bilirubin is normal, look for ICG 15% and follow

• Preoperative evaluation • Liver function: Child score, MELD score • FLR volume- • Liver augmentation

• Parenchyma sparing resection • Removal of liver segments than lobes • Anatomic : Segmentectomy/Sectionectomy • Non anatomic- Wedge resection, enucleation • Major - > 3 liver segments • Minor < 3 liver segments

• IOUS< ICG
• • Non anatomic resection is not inferior to anatomic resection in terms of DFS and OS • Decreases risk of post hepatectomy liver failure • Decreases post operative complications
• Preserve Oncologic outcomes-CRLM and NELM ⇒ here we can do any type

• HCC and IHC - Can be done = there is no good consensus here but preferably do anatomical here

• Anatomic resection margin • Surgery that removes territory of one or more third order portal branches

CRLM • No difference between anatomic or non anatomic resection • 1 cm resection margin is adequate • (+)ve margin - Decrease DFS but OS remains same • R1 vascular can be done to preserve parenchyma

When do you operate in HCC?

• Ideal candidate:
  • No cirrhosis / Child A cirrhosis / early child B
  • No CSPH = no high grade varices / platelets >1.5 lakh / HVPG < 10
• Anatomic resection >> Non Anatomic resections ( retrospective data)
• Invades porta territory

• Satellite Nodule

  For LIVER resection in case of Portal hypertension cases:

  

• Meso hepatectomy = Central / taj mahal = Segment 5,8 and 4b

• Mini meso hepatectomy = Segment 8 and 1 removal
• Anterior approach of Hepatectomy :
  • Parenchymal transection is done before liver mobilisation
  • Used for bulky tumors at cava heaptic vein junction
  • Anterior approach decreases tumor spillage and decreases recurrence
  • use the tunnel between RHV and MHV at the IVC to hang the liver and resect parenchyma from anteriorly
  • Hanging maneuver cannot be used for tumors in contact with anterior surface of IVC
• PRINGLE MANEUVRE :
  • HEMODYNAMIC RESPONSE TO
    • Decrease Preload
    • Increase Portal pressure
    • Increase in Mean arterial pressure = paradoxical = due to sympathetic response from HA clamping
    • Increase in SVR = almost always in every clamping this increases in response to decreased preload
  • Duration of Pringle maneuver :
    • Normal liver = 60 mins
    • damaged liver = 30 mins
    • Generally continuous pringle is not advised
    • we do intermittent pringle= 15 -20 mins clamp and then 5-10mins remove clamp ; this way we can go for 1 hr of clamping time cumulative
• Total Hepatic Vascular Exclusion:
  • Sequence of Clamping in THVE
    • Fluid loading —> Pedicle clamping ( pringle) —> Infrahepatic IVC —>assess the hemodynamic response and if Bp doesnot fall —> Suprahepatic IVC clamping
  • Hemodynamic response
    • Decrease Cardiac preload
    • Decrease in Pulmonary artery Pressure
    • Decrease in cardiac index
    • DECREASE IN MAP = because here we are clamping the IVC as opposed to Pringles where we clamp only Portal pedicle
    • Increase in HR and SVR

• Portal Vein Embolisation:

  • one of the ways of Liver Augmentation = Atrophy - hypertrophy complex
  • Generally we do it for right sided resections as the left lobe needs augmentation
  • different approaches:
    • Percutaneous approach
      • Ipsilateral - Directly puncture the liver to be resected = difficult because of short extrahepatic course - but preferred approach
      • Contralateral - we puncture the FLR = we puncture segment 3 branches via subxiphoid route for right embolisation
    • Laparotomy - trans iliocolic approach
  • Absolute Contraindications:
    • Established PHTN
    • Portal Vein Thrombosis
  • Degree of Hypertrophy > 5% + sFLR >20% ⇒ good response
  • Kinetic Growth rate > 2% per week

  • Segment IV vein is also embolised for better hypertrophy

    • Therefore, in calculating the FLR volume for patients undergoing extended right hepatectomy, in which the middle hepatic vein will be removed or compromised, segment IV volume should not be included. This is because in the absence of middle hepatic vein drainage, most of segment IV will become congested and lose its normal function.

    

  

  LVD(Liver Venous Deprivatoin)

  • Kobayashi
  • Simultaneous Hepatic Vein Embolization with PVE
  • More hypertrophy than PVE alone

Associating Liver Partition and Portal Vein Ligation

• Dr. Hans Schlitt - initiated the concept of ALPPS
• Indication:
  • Bilateral Colorectal Liver Metastases
  • HCC
  • Hilar Cholangiocarcinoma
• Benefits:
  • More volume hypertrophy than PVE and less time to hypertrophy also
• Challenges:
  • Higher morbidity and mortality
• Variant:
  • Rescue ALPPS ⇒ done after failure of PVE
• Technique:
  • Only right portal vein is ligated
  • Liver transection is done
  • Surgery is done after 7-14 days
  • Hepatic artery and hepatic vein along with duct are transected

Outcome

• Post hepatectomy liver failure: most severe
• Biliary fistula: most common
• Collections
• Li Gro trial: ALPPS is not inferior to two-stage liver resection

Laparoscopic Liver Resection

• 2008 Louisville
  • Less than 5 cm in peripheral segment
• 2014 Morioka

Anterior Approach

• Conventional Hepatectomy:
  • Liver mobilization is done first
  • Inflow control = RPV RHA
  • Outflow control
  • Transection of liver

• Anterior:

  • First step is Inflow Control
  • Liver parenchyma transection is done before mobilization

• Hanging Maneuver (Belghiti):

  • Extension of anterior approach; can also be used for conventional approach
  • Steps:
    • Pringle maneuvre done
    • space created between RHV and MHV
    • Space created between Liver and IVC by creating a tunnel
    • Surgical tape is placed between the liver and the anterior surface of the IVC
    • here we do Glissonian pedicle approach and ligate right pedicle enmasse with stapler
    • line of demarcation occurs now and liver is transected
    • RHV is divided last after hanging the liver
  • Reduces blood loss
  • Decreases tumor rupture
  • Suitable for large right lobe tumors

Minimeso hepatectomy: