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Liver Transplantation

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Title: Liver Transplantation


1
Liver Transplantation
Dr. Prashant Kumar
University College of Medical Science GTB
Hospital, Delhi
2
Liver Transplantation
  • Liver transplantation (LT) is now established as
    the only definitive treatment for end stage liver
    disease (ESLD)
  • Starzl et al carried out 1st human liver
    transplant in 1963
  • Survival following liver transplant
  • 1 year survival 87 93
  • 3 year survival gt 75
  • .....(http//www.ustransplant.org The 2009
    Annual Report of the OPTN and SRTR Transplant
    Data 1999-2008).

3
Types of Liver transplant
  • Orthotopic liver transplantation
  • Donor liver is transplanted in normal anatomic
    position
  • Commonly practiced
  • Heterotopic liver transplantation
  • Donor liver is placed within abdominal cavity
    with patients native organ occupying the normal
    anatomic position
  • Problems with Heterotopic LT
  • difficult to accommodate an extra organ in
    abdomen with a complex blood supply
  • danger of multiple anastomosis leak, kinking or
    compromised

4
Indications for Liver Transplantation
  • Epidemiology of ESLD differs from country to
    country and in different age groups.
  • The common indications for LT
  • Adults- alcoholic liver disease, chronic active
    viral hepatitis (C, B, non-A non-B),
    cryptogenic cirrhosis, PBC and malignancy.
  • Paediatric patients cirrhosis (40), extra
    hepatic biliary atresia (38) and fulminant
    hepatic failure (11).

5
. Indications for Liver Transplantation
Chronic Diseases
  • NON-CHOLESTATIC CIRRHOSIS
  • Alcoholic
  • Viral (Hep A, B C)
  • Autoimmune
  • Cryptogenic
  • Drug induced
  • CHOLESTATIC LIVER DISEASE
  • Primary biliary cirrhosis
  • Secondary biliary cirrhosis
  • BILIARY ATRESIA
  • Extra hepatic biliary atresia
  • Hypoplasia
  • NEOPLASMS
  • Cholangiocarcinoma
  • Hepatocellular carcinoma (single tumorlt 5cm or
    less than 3 tumors lt 3cm)
  • METABOLIC DISEASES
  • Alpha-1 Antitrypsin deficiency
  • Wilsons disease
  • Haemochromatosis
  • Tyrosinaemia
  • Glycogen storage disorders
  • Amyloidosis
  • OTHER
  • Cystic fibrosis
  • Budd-Chiari syndrome
  • Neonatal hepatitis
  • Familial cholestasis
  • Polycystic liver disease

Fulminant Hepatic failure
  • Drug induced
  • - Acetaminophen
  • - Idiosyncratic
  • Ingestion of poisionous mushrooms/ herbs
  • Secondary to viral hepatitis

6
Contraindications
  • Relative
  • Advanced CRF
  • Psychosocial factors like Active alcohol or drug
    abuse, poor social support
  • Psychiatric diseases Poor compliance
  • Hypoxemia with intrapulmonary right to left shunt
  • Prior portocaval shunting
  • Prior complex hepatobiliary Sx
  • Portal vein thrombosis
  • Advanced cholangiocarcinoma
  • ?? Age gt65 yrs
  • ?? Hepatitis (HBsAg HBeAg ve)
  • ?? HIV ve without clinical AIDS
  • ?? Advanced malnutrition
  • Absolute
  • Sepsis outside hepatobiliary tree
  • Advanced/metastatic hepatobiliary malignancy
  • Advanced cardiopulmonary disease (CAD/ cardiac
    dysfunctions/ pulm HTN)
  • AIDS (not only HIV)
  • ?? ICT in case of fulminant liver failure

7
Liver Donor
Sources of Liver Graft
  • Deceased (brain dead) donor liver transplantation
    (DDLT) main stay in West
  • Living donor transplantation (LDLT)
  • Base on the concept that liver has high
    regenerative capability
  • Common in eastern countries India- ethical,
    social religious issues surrounding concept of
    brain death pose hindrance to brain dead liver
    donation (inadequate deceased donor organ
    donations)
  • In adult-to-adult LDLT, larger right lobe of
    donor is used (segment V, VI, VII VIII)
  • Graft size 500-1000gram, donor is left with 1/3rd
    of original mass
  • In children only left lateral segment (II III)
    or entire left lobe (II, III, IV) can be used
    depending on the weight of the recipient.
  • Left hepatectomy is less complex require less
    surgical time.

8
. Liver Graft Sources
Liver Donor
  • Advantages of LDLT
  • Hemodynamic stability of donor- better graft
    quality
  • Reduced cold ischemia time
  • Reduced waiting time
  • Elective nature of procedure permitting optimal
    preparation of recipient
  • Problems of LDLT
  • Donor morbidity
  • High incidence of hepatic artery thrombosis
  • Controversy of Living liver donation
  • Ethical issues, social stigma, quality of life
    after donation, financial impact on donor

9
. Liver Graft Sources
Liver Donor
  • Split Grafts
  • Limited availability of suitably sized paediatric
    livers has led to development of Split Grafts in
    which a single donor organ may be split for
    multiple transplants
  • Problems
  • more complications
  • excessive bleeding tissue necrosis may occur
  • reduced survival rate in recipients
  • high incidence of hepatic artery thrombosis

10
Scoring systems
 
CHILD-TURCOTTE - PUGH SCORE
Measure 1 point 2 points 3 points
Total Bilirubin  (mg/dl) lt 2 2-3 gt3
Serum albumin (g/dl) gt3.5 2.8-3.5 lt2.8
INR lt1.7 1.71-2.3 gt 2.3
Ascitis None Slight/Suppressed with medication Moderate despite diuretics/Refractory
Hepatic encephalopathy None Grade I-II Grade III-IV
CTP score - Disease severity for pts with
ESLD - Used to predict peri-operative mortality
in patients with liver disease.
11
Points Class Life expectancy Perioperative mortality
5-6 A 15-20 years 10
7-9 B Candidate for transplant 30
10-15 C 1-3 months 82
  • Shortcomings of CTP scores
  • Subjective nature of the assessment of
    ascitis encephalopathy
  • Limited discrimination into only three
    disease severity categories

12
Liver Donor
Donor Liver Allocation
  • In US, patients name and condition is entered in
    National Registry.
  • CTP (CHILD-TURCOTTE - PUGH SCORE) scores in
    conjunction with United Network for Organ Sharing
    (UNOS) status determining factor was used for
    organ allocation in the USA until early 2002. but
    it did not always ensure that organs were
    allocated to the sickiest patients with the
    greatest risk of mortality.
  • Now, Model for End-Stage Liver Disease (MELD) is
    used for allocating liver to recepients.
  • In India, there is no such national registry or
    liver transplant centre registry.

13
Model for End-Stage Liver Disease (MELD)
  • MELD score 0.957 x Loge (creatinine mg/dl)
    0.378 x Loge (bilirubin mg/dl) 1.12 x Loge
    (INR) 0.643
  • Multiply the score by 10 and round to the
    nearest whole number
  • Established in Feb 2002
  • Numerical scale, from 6 (less ill) to 40
    (gravely ill), for 12 yrs
  • This score tells us how urgently LT is required
    within next 3 months
  • Most patients on LT waiting list have MELD score
    between 11 and 20
  • Some modifications required like in
    Hepatocellular carcinoma- rapid progression to
    inoperable before changes in MELD score
  • MELD-Na Recently developed is under
    evaluation. Serum sodium conc. have been
    suggested as useful predictor of mortality in
    patients with ESLD awaiting LT.

14
Donor Selection
Liver Donor
  • ABO Blood typing
  • Most important matching for liver transplant
  • Donor and recipient ABO blood type matching can
    be classified as follows
  • identical (e.g. A to A) Preferred, best graft
    survival
  • compatible (e.g. O to A) Acceptable graft
    survival
  • Incompatible (e.g. A to O) Only in exceptional
    cases of acute hepatic failure with
    non-availability of matched donor, poor graft
    survival.
  • Exclusion of viral hepatitis or hepatic
    dysfunction
  • History Physical examination
  • Detailed imaging of donor liver

15
Living Liver Donor Preparation
Liver Donor
  • Extensive medical, Psychological counselling,
    Legal formalities
  • Primary presurgical consideration determination
    of mass of transplanted liver that is needed to
    support a given patient and to leave enough liver
    mass with donor
  • Graft- recipient body weight ratio
  • Graft weight as percentage of liver mass
  • Donors liver regains its original size in short
    time- weeks to months. Functional time may take
    much longer time
  • Healthy, ASA grade I II
  • PAC orders
  • Autologous blood transfusion of 2 Unit WB planned
  • Anxiolysis Benzodiazepines

16
Anesthetic Considerations in Donor
Liver Donor
  • Concern
  • Extensive hepatic surgery
  • AIM
  • Hemodynamic stability of donor
  • Adequate blood supply to liver during surgery
    (quality of graft)
  • Anesthesia technique
  • Standard general anesthesia alone or with
    Thoracic epidural catheter
  • Monitoring
  • Minimal standard monitoring
  • Arterial line
  • CVP line
  • Two large bore IV canulae
  • Ryles Tube
  • Position
  • Supine, one arm tucked to side, other arm
    abducted

17
Anesthetic Considerations in Donor
  • Incision
  • L shaped (hockey stick) or standard bilateral
    subcostal incision with midline extension
  • Stages of surgery
  • 1. mobilization of liver identification of
    vasculature structures decreased venous return-
    hypotension
  • 2. Transection of liver
  • 3. Hemostasis and closure
  • Blood fluids
  • Low CVP- decrease blood loss
  • Restrict fluid until donor liver lobe removed
  • Blood loss 1 L, be prepared for sudden
    extensive blood loss
  • Extubated at the end of surgery
  • Closed monitoring in Post- op room
  • ICU care not always required
  • Post Operative pain relief
  • Epidural analgesia
  • Patient controlled analgesia
  • Post- operative complications

18
Preservation of liver of deceased patient
Liver Donor
University of Wisconsin preservation fluid (UW solution) Euro-Collins solution
Impermeants Raffinose, lactobionate Glucose
Hydrogen ion buffers KH2PO4 KH2PO4, K2HPO4 NaHCO3
Colloid Hydroxyethyl starch
Metabolites others MgSO4, Adenosine, Glutathione, Allopurinol, Insulin, Dexamethasone KCl
Osmolarity (mmol/L) 320 335
Max. ischemia time 24 hrs. atleast 8 hrs. for donor livers
UW solution has allowed LT to become a
semielective procedure, esp because of
impermeants with improved enzyme function,
decrease blood use, shorter hospital stay
19
Pathophysiology of ESLD
Liver Recipient
Organ Consequences Anesthetic Implications/Action
CNS Encephalopathy Ammonia level monitoring
CNS brain edema/ ?ICP/ Neurological function impairment ICPgt 25mmHg Osmotic therapy with mannitol/ hypertonic saline/ mild hypothermia/ broad spectrum antibiotics/ barbiturate coma/ MARS (molecular adsorbents recirculating system) ?? ICP Contraindication of LT
CVS Hyperdynamic circulation Reduced SVR HR ?, BP N/? Cardiac evaluation needed maximum possible optimization
CVS CO ? (?- if cardiomyopathy) Cardiac evaluation needed maximum possible optimization
CVS CAD/ Atherosclerosis Dobutamine stress test
CVS Increased plasma volume
CVS Pericardial effusion
20
Organ Consequences Anesthetic Implications/Action

Pulmonary Hepatopulmonary syndrome (hypoxia PaO2lt 60) Increased mortality Independent indication of LT Improves after LT
Portopulmonary syndrome ( Pulm Hypertension) may worsen after LT Treatment of pulmonary HTN
Pleural effusion If significant chest tube placement
Interstitial edema
Atelectasis Deep breathing exercise, incentive spirometry
V/Q mismatch shunting
Restrictive lung disease due to Ascites pleural effusion Drainage results in transient relief
21
Organ system Consequences Anesthetic Implications/Action
Endocrine Glucose intolerance Hyperglycemia
Endocrine Diminished glycogen stores Hypoglycemia frequent blood sugar monitoring replacement
Haematologic Anaemia Consider blood transfusion
Haematologic Reduced clotting factor levels Deranged coagulation
Haematologic Thrombocytopenia (Hypersplenism) Deranged coagulation
Gastrointestinal Esophageal varices, portal hypertension, and ascites Bleeding during Ryles tube insertion Respiratory compromise
Gastrointestinal Delayed gastric emptying Consider as full stomach
Gastrointestinal Reduced clearance of fibrinolytic substances tissue plasminogen factors
22
Organ system Consequences Anesthetic Implications/Action
Renal Oliguria (10 renal disease, Hepatorenal syndrome, ATN, Prerenal azotemia) spontaneous bacterial peritonitis risk factor renal function improves with LT Severity of renal dysfunction correlates with mortality after LT
Renal Hyponatremia pre-operative correction needed if significant
Renal Hypokalemia (poor nutrition, diuretics, intestinal losses) pre-operative correction needed if significant
Hepatic Hypoalbuminemia, coagulation factor deficiency, drug metabolism alteration Effect on various organs Alteration in drug pharmacokinetics and pharmacodyanamics
23
Preoperative assessment
  • History Examination Various organ functional
    status in addition to routine PAC
  • Pre- operative optimization
  • Many derangements of ESLD neither correctable
    nor desirable until LT
  • Major emphasis in PAC on identification of most
    important areas of physiologic compromise
    treating only those that threaten safe conduct of
    anesthesia
  • Patient to be in the best possible condition
    before surgery

24
Preoperative assessment
Investigations
  • Haemogram with platelet count
  • LFT seum proteins
  • KFT serum electrolytes with creatinine
    clearence
  • RBS
  • Coagulogram (PT/PTTK, BT, CT)
  • ABG
  • ECG ECHO
  • Chest x ray PFT

25
PAC orders
  • Consent with risk explanation for each procedure,
    post- operative ventilatory consent
  • NPO
  • Aspiration prophylaxis
  • Short acting benzodiazepine (caution only if
    anxiety- sedation, respiratory depression, long
    action- dose titration needed)
  • Antibiotic and immuno-suppressants (e.g., steroid
    administration)
  • Arrangement of blood and blood products varies
    with hospital protocol
  • Blood products may include 10 U PRBC, 10 U of
    FFP, with 4 U of single donor platelets
  • Additional blood products should be available

26
Anaesthesia Equipment
  • Provision of quality anaesthesia care for LT
    demands a good infrastructure 
  • Advance Anesthesia machine
  • Multiple channel vital sign monitor for advanced
    haemodynamic monitoring
  • Warming mattress, warming blanket, blood warmers
  • High volume/ Rapid infusing systems, Syringe
    infusion pumps
  • Veno - venous bypass system
  • Thrombo- elastography (TEG)
  • Cell saver
  • Laboratory facilities for prompt analysis of
    blood samples  

27
Monitoring
  • Minimum Mandatory Monitoring NIBP, ECG, HR,
    Pulse oxymetry, capnography, temperature
  • Neuromuscular monitoring
  • IBP
  • CVP in all pts/ Pulmonary artery (PA) catheter
    (in selected cases).
  • Transoesophageal echocardiography (TEE)
    management of fluid therapy, cardiac function,
    diagnosis of intra-op complications like
    pulmonary embolus.
  • Risk ?ed Variceal bleed
  • Regular lab monitoring of ABG- oxygenation, base
    deficit, lactates, SE (sodium, potassium and
    ionized calcium), blood glucose, Hb, platelet
    count, PT/PTTK, and fibrinogen levels
  • TEG (Thrombo- elastography)
  • Urine Output/ Fluid Input

28
Vascular Access
  • 2-3 Large bore peripheral IV access. Venous
    cannulae in upper half of body be inserted.
    Fluids administered through lower body cannulae
    are lost in surgical field
  • Sites designated for Veno Venous Bypass should be
    avoided
  • Invasive lines
  • ??? Before induction or after induction
    (Preferred)
  • Correction of severe coagulopathy before line
    placement may be considered, USG may facilitate
    central venous cannulation/PAC
  • Radial arterial line for IBP monitoring

Epidural Catheter
  • Not inserted in view of prolonged perioperative
    coagulopathy

29
Opioids
Drug Alt. in PK Effect Comments
Fenatnyl Elimination ?? as completely metabolized by liver, also highly protein bound ? / prolonged Single dose PK not altered, administer cautiously
Sufentanil -do- -do- -do-
Alfentanil ? plasma clearance -do- Not preferred
Morphine ? Metabolism, ? elimination t½, ? protein binding, extrahepatic metabolism nt ? Sedative depressant effect, not modified pharmaco-dynamics Administration interval ? 1.5-2 fold
Remi-fentanil Rapidly hydrolized by plasma esterase, rapid elimination and recovery independent of dose Unaffected Preferred
30
IV induction agents
Drug THBF Clearance Comments
Thiopentone ? (? CO ? hep artery resistance) Mild ? Hep extraction 15, elimination t½ not changed
Propofol (spanchnic vasodilation) Unaltered Highly protein bound still not much changes in pharmacokinetics
Etomidate ? (? CO) -
Ketamine Unaltered Product named Norketamine excreted by liver, hence not preferred
31
Neuromuscular blockers
Drug PK Clearance Comments
Vecuronium Hep elimination metabolism (60) ? ? Elimination t½, ? NMB
Rocuronium Hep elimination (70) ? ? Vol of distribution, ?NMB
Pancuronium Hep elimination metabolism (80) ? ? Elimination t½, ? NMB
Atra / Cisatracurium Unaltered in CLD Unaltered Preferred
Scoline ? Hydrolysis in liver disease as ? plasma CHE Preferably avoided, although clinically action not prolonged
  • Caution
  • NMB monitoring to be done
  • Facility of postop ventilation to be ensured

32
Volatile Anaesthetics
Drug HAF PBF Buffer response THBF O2 delivery
Halothane ?? ?? Blunted ?? ? (? hep venous sat.)
Enflurane ? ?? Blunted ? ?
Iso ?/? ? ?/? ?/?
Sevo ? ? ? ?
Des. ? ? ? ?
  • In summary, influence of volatile anaesthetics on
    HBF and function is complex and related to not
    only the drug but also to patient related
    variables like severity of underlying
    neurodysfunction, age, surgical stress etc.

33
Summarising Drugs
Drug Safe Caution C/I
Premedication Lorazepam Mida., Diaz.
Induction Propofol Thio., Etomidate
Maintenance Des., Sevo., Iso., Nitrous Enflurane Halothane
Muscle relaxants Atra., Cistra. Pan., Vec., Scoline, Rocu.
Opioids Remi. Fenta., Alfen., Morph., Pethi
Analgesics PCM NSAIDs, Lido., Bupi
34
Induction of Anaesthesia
  • RSI due to emergency nature of surgery, delayed
    gastric emptying, gross ascitis, active GI
    bleeding or encephalopathy
  • Opioids Fentanyl/ sufentanil/alfentanil
  • Induction agent propofol, thiopental, or
    etomidate
  • Muscle relaxant SCh (Plasma pseudocholinesterase
    levels ? in liver disease, resultant
    prolongation of SCh effect of no clinical value,
    caution potassium level)
  • NG tube (stomach decompression- improve surgical
    exposure early enteral feeding in post-op.
    period )
  • chances of bleeding during NG insertion
  • Post- induction hypotension
  • Very low SVR Relative hypovolemia
  • t/t Small amount of vasoconstrictors
    (phenylephrine)

35
Maintenance of Anaesthesia
  • Nitrous oxide Intestinal distension avoided
  • Balanced anesthesia technique with volatile
    anesthetics in oxygen/air mixture and opioids
    provide stable haemodynamics
  • Opioids fentanyl, sufentanil, alfentanil, and
    remifentanil
  • Isoflurane commonly used (splanchnic vasodilator
    properties, HABF preserved by preservation of
    autoregulation)
  • Muscle relaxant Cisatracurium or Atracurium
    preferred over vecuronium
  • Neuromuscular monitoring recommended
  • TIVA with propofol (S/E cardiac depression after
    reperfusion occurs)

36
Blood Fluids
  • Severe coagulopathy intraoperative blood loss
    remain the most significant problem
  • Bleeding during pre-anhepatic phase of surgery is
    related to previous abdominal surgery, degree of
    pre-existing coagulopathy, severity of portal HT,
    duration/ complexity of surgical procedure.
  • Impaired hemostasis, esp. after receiving a
    suboptimal or marginal liver, is usually
    multifactorial and includes
  • Hyperfibrinolysis
  • depletion of coagulation factors
  • thrombocytopenia
  • platelet dysfunction.

37
Blood Fluids
  • Administration of FFP, RBC, platelets and
    cryoprecipitate remains mainstay of therapy for
    blood loss and coagulopathy.
  • Pharmacologic agents known to alter hemostasis ,
    investigated as adjunctive therapies
  • Aprotinin
  • Epsilon-aminocaproic acid
  • Tranexamic acid
  • Conjugated estrogen
  • No consensus on their use.
  • Risk of thrombus formation
  • Recombinant factor VIIa, has recently attracted
    significant attention for improving coagulopathy
    and reducing intraoperative blood loss. It
    increases thrombin generation in conjunction with
    activated platelets

38
Blood Fluids
  • Use of autologous transfusion
  • Single donor platelets prepared by pheresis
    technique used
  • Use of blood salvage system (cell saver) except
    in malignancy infected ascitic fluid
  • Central venous pressure
  • Normal Vs Low CVP

39
Operation
Incision
Positioning
  • Supine with one or both arms abducted to a
    maximum of 70 degrees
  • Abduction beyond this angle can result in
    brachial plexus injury
  • Long duration surgery Care of eye, pressure
    points

Inverse T or Mercedes incision
40
Stages of Operation
Preanhepatic/ dissection phase
Anhepatic phase
Neohepatic phase
Dissection of structures of porta hepatis
mobilization of native liver
begins when native liver is removed after
transection of blood supply occlusion of supra-
and infra- hepatic IVC implantation of donor
liver
involves the completion of several anastomoses,
haemostasis, and closure.
41
Pre- Anhepatic phase
  • Surgical goals
  • Mobilization of vascular structures around liver
    (supra-hepatic IVC, infra-hepatic IVC, portal
    vein, and hepatic artery)
  • Isolation of CBD
  • Removal of adhesions between liver, diaphragm,
    and retroperitoneal areas to allow full
    mobilization of liver within right upper quadrant
    significant Blood loss

42
Pre-Anhepatic phase
Problem Cause Management
Hypovolemia Drainage of ascites Blood loss due to dissection of adhesions between liver, diaphragm and retroperitoneal areas. colloid containing fluids Maintain CVP around 10 Blood products depending on lab results, Goal Hb 9 gm, platelets gt 70000, INR 1.5, U/O 1 ml/ kg/ hr.
Hypotension Hypotension in spite of adequate volume is due to manipulation of liver, compression of IVC. Communicate with surgeon. Ask to remove packs look for compression of IVC
Citrate intoxication, ionized hypocalcemia Transfusion of citrate-rich blood products in the absence of hepatic Function Administration of calcium gluconate according to lab reports
43
. Pre-Anhepatic phase
Problem Cause Management
Hyponatremia Pre- operative derangement Loss of ascitic fluid Avoid aggressive treatment. Intra-op ? of gt 32mEq- Pontine myelinolysis
Hypokalemia Pre- operative derangement Loss of ascitic fluid Avoid aggressive treatment. Will increase after reperfusion
Arrythmias Handling of liver Compression of IVC Hypocalcaemia (because of citrate intoxication) Hypomagnesaemia Ask surgeon to stop handling Correct hypocalcaemia, maintain ionized calcium gt 1.2nmol
Hypothermia Rapid fluid shift Large surgical area exposure Infusion of warm fluids, Baer Hugger, warm blanket increasing temperature of room.
44
. Pre-Anhepatic phase
  • Rest management of this phase is mainly as
    patient of severe liver failure undergoing major
    laparotomy
  • Diuresis be established early for renal
    protection in anticipation of relative renal
    ischemia during anhepatic period
  • During end of dissection stage, the donor organ,
    which is stored in preservation solution, is
    flushed with crystalloid or colloid solution on a
    separate table (back table).

45
Anhepatic Phase
  • New liver is implanted by one of two techniques
  • Infra- Caval interposition
  • Piggy-back technique
  • Infra- Caval interposition
  • involves removal of the native liver along with
    intra-hepatic portion of IVC.
  • Complete vascular occlusion by clamping hepatic
    artery, portal vein, supra- and infra hepatic
    IVC decreases venous return by as much as 50.
  • Veno Venous Bypass (VVBP)
  • When VVBP is not used Test clamps applied on
    infra hepatic IVC. If patient tolerates,
    permanent clamps applied.
  • Before this step, maintain CVP b/w 10-15 cm of
    Hg, cut down inhalation agent, use of small
    amount of vasoconstrictors

46
Veno Venous Bypass (VVBP)
  • Diverts IVC portal venous flow to axillary vein
  • Initiated after cannulation of femoral portal
    vein, axillary or subclavian vein on left side
  • Continuous pump diverts blood from portal and
    femoral vein to suprahepatic veins.
  • Attenuates the decrease in preload, improves
    renal perfusion pressure, lessens splanchnic
    congestion, and delays the development of
    metabolic acidosis

47
Veno Venous Bypass VVBP
  • Advantages
  • Disadvantages
  • Improved hemodynamic stability
  • Improved perfusion of organs during anhepatic
    phase
  • Decreased RBC fluid requirements
  • Splanchnic decompression
  • Reduced renal impairment
  • Limited metabolic impairment
  • Reduced incidence of pulmonary edema.
  • Complications related to cannula placement
    (most significant)
  • Hematoma
  • Major Neuro-vascular injury,
  • Pulmonary air embolism
  • Thromboembolism
  • Inadvertent decannulation (may be fatal or result
    in significant morbidity)
  • Even death has been associated

Recent data shows most centers do not use VVBP
routinely
48
Piggy-back Technique
Allows removal of liver without removing a
portion of the vena cava. One end of donor IVC
is closed and other end is anastamosed to
recipient IVC end to side. Temporary porto-caval
shunt is performed to reduce the portal
pressure. Adv. improved haemodynamics
Disadv. surgically more difficult than caval
49
.. Anhepatic phase
Anaesthetic problem Anaesthetic management
Worsening coagulopathy. No production of clotting factors, fibrinogen deficiency. Thrombocytopenia Fibrinolysis prevented . Attenuated by antifibrinolytics (e.g. aprotinin or tranexamic acid)
Absent citrate / lactate metabolism, reduced gluconeogenesis and glucose uptake, worsening metabolic acidosis. Treatment of hypoglycemia. Methylprednisolone 10 mg/kg before reperfusion to protect against graft dysfunction and renal injury
Fibrinolysis may begin during this stage, caused by an absence of liver-produced plasminogen activator inhibitor, which results in the unopposed action of tissue plasminogen activator. The use of antifibrinolytics varies among centers
50
Neohepatic / Reperfusion Phase
Anaesthetic problem Anaesthetic management
Increase in preload, ? SVR Hypotension Hemodynamic instability Epinephrine (25-50 - 1µg) boluses with or without infusions of vasopressor or inotropic support
Life-threatening hyperkalemia Cardiac arrest Detected on ECG Calcium chloride and sodium bicarbonate If time permits, albuterol and insulin are also effective
51
.. Neohepatic Phase
  • Signs of good graft function which are seen in OR
    are
  • correction of acidosis
  • production of bile from graft
  • maintenance of serum calcium, potassium blood
    glucose level
  • increase in body temperature
  • coagulation state returns to normal
  • Decreased calcium requirement
  • increase in CO2 levels

52
Post- Reperfusion Syndrome (PRS)
  • Physiologic perturbations seen in immediate
    reperfusion phase
  • Is characterized by MAP of lt 60 mm Hg pulmonary
    HT occurring within first 5 minutes of
    reperfusion of graft and persisting atleast 1
    minute
  • Approximately one in three patients undergoing
    OLT have profound hypotension after reperfusion.
  • Cause is uncertain
  • number of factors such as hyperkalemia, acidosis,
    hypothermia, emboli, cytokines, activation of
    compliments and vasoactive substances have been
    implicated.

53
Post- Reperfusion Syndrome (PRS)
  • Several factors or in combination are postulated
    to produce this hemodynamic instability
  • high potassium concentrations in the preservative
    solution (UW solution)
  • donor demographics
  • Surgical technique
  • Sub optimal graft
  • graft cold ischemia time gt 6 hrs
  • Use of VVB
  • Ionotropic support may be needed to reverse
    myocardial depression.
  • Attention should be paid to diagnosis
    management of haemostasis and temperature

54
Post operative ventilation
  • No longer mandatory
  • Recent studies have reported that up to 75 of
    first-time cadaveric liver transplant patients
    without fulminant failure could be extubated in
    OR by physicians who had experience with early
    extubation protocols
  • Standard criteria for extubation in addition to
    some patient-specific considerations
    (e.g.,significant preoperative hepatic
    encephalopathy, fulminant hepatic failure) be
    considered for extubation
  • Admit patients to ICU for close monitoring
    purposes for atleast first 24-48 hrs.

55
Post operative concerns
  • Monitoring and stabilization of the major organ
    systems- cardiac, renal, hepatic and
    corresponding relevant investigations (serum
    glucose, electrolytes, KFT, LFT, coagulation,
    Hemogram, Platelet)
  • Evaluation of graft function
  • Achievement of adequate immun-osuppression
  • Detection, monitoring, and treatment of
    complications directly and indirectly related to
    the transplant
  • Postsurgical pain control not a major problem.
    Analgesic requirements are decreased, exact
    mechanism not known
  • Paracetamol
  • Short acting opioids like fentanyl through
    patient controlled analgesia devices.

56
Complications of LT
  • Primary Nonfunction
  • (up to 5)
  • characterized by encephalopathy, coagulopathy,
    minimal bile output, and progressive renal and
    multi organ dysfunction
  • with increasing serum lactate level,
    increasing metabolic acidosis, rapidly rising
    liver enzymes histological evidence of
    hepatocyte necrosis in absence of any vascular
    complication.
  • Donor risk factors implicated in primary graft
    dysfunction
  • prolonged cold ischaemia time
  • unstable donor
  • high level of steatosis in the liver allograft
  • older donor
  • high serum sodium level in the donor

57
. Complications
  • Patients with initial primary dysfunction may
    recover with support but those who progress to
    show evidence of extra hepatic complications such
    as hemodynamic instability, renal failure or
    other organ systems dysfunction may require
    urgent re-transplantation.  
  • 2. Hepatic artery thrombosis leads to graft
    necrosis. Patency of HA is determined by Doppler
    USG. Early intervention can salvage graft
    prevent need for regrafting.
  • 3. Biliary leak or obstruction
  • 4. Nonspecific Cholestasis
  • 5. Haemorrhage
  • 6. Portal vein thrombosis (rare)

7. Vena caval thrombosis (rare) 8.
Intraabdominal sepsis 9. Neurologic
complications 10. Immunosupprission
58
Paediatric Liver transplantation
  • PELD - Pediatric End Stage Liver Disease score
  • (0.436xAge) - (0.687xLN(Albumin))(0.480x
    LN(bilirubin)) (1.857x LN(INR)) (0.667 x
    growth failure) x 10
  • PELD score ranges from negatives to 150
  • Age lt 1 year gets 1 point, Age gt 1 year gets 0
    points
  • growth failure 1 point, no growth failure 0
    points
  • Swan Ganz not used
  • CVP line two large peripheral lines usually
    sufficient.
  • Femoral foot arterial lines not desired as
    aorta could be cross clamped for hepatic artery
    anastomosis.

59
. Paediatric Liver transplantation
  • Incidence of hepatic artery thrombosis is twice
    that of adults less vigorous correction of any
    clotting defects. An INR of 1.51.8 at the
    conclusion of surgery is considered ideal.
  • Venovenous bypass is not used in pediatric
    recipients.
  • Children tolerate vena caval clamping better than
    adults
  • less hemodynamic changes are seen.
  • Reperfusion
  • lesser hemodynamic changes or rhythm disturbances
  • Maintaining normothermia in children very
    difficult
  • Rapid infusion devices usually unnecessary in
    pediatric recipients.

60
Anaesthesia for Patients after LT
  • Liver transplant recipients may return to OR
    shortly for exploratory laparotomy for bleeding,
    biliary leak, bowel obstruction, abscess
    formation
  • Liver function may not have returned to baseline
    in immediate post-transplant period
  • Additional surgical stress may result in
    significant worsening of hepatic function.
  • Coagulation studies be monitored / FFP be made
    readily available.

61
Anaesthesia for Patients after LT
  • MC reason to operate after LT biliary
    reconstruction.
  • Liver function is generally normal
  • Anaesthetic considerations (including RA such as
    epidural) similar to those for any abdominal
    procedure
  • On powerful immunosuppressive therapy (increased
    risk for infectious complications, malignancy,
    drug toxicity, and adverse drug interaction).
    Hence, placement of intravenous, epidural
    catheters should be performed under absolute
    sterile conditions with maximum barrier
    protection
  • Drug interaction with immunosuppressant drugs

62
References
  • Millers Anesthesia, 7th ed.
  • Redai I, Emond J and Brentjens T. Anesthetic
    considerations during liver surgery. Surg Clin N
    Am 84 (2004)40111.
  • Murthy TVSP. Transfusion support in liver
    transplant. Ind J Anaesth 200751(1)13-19
  • International volume of Anesthesia Prys Roberts
    2nd edition
  • A practice of anesthesia Wylie and Chulchill
    davidsons 7th edition
  • Yao Artusios Anesthesiology
  • The 2009 Annual Report of the OPTN and SRTR
    Transplant Data 1999-2008 (http//www.ustransplant
    .org)

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