Mod13: Liver Transplants

Question 1

_{Liver Transplants}

Where are liver tpx performed?

Answer 1

in many centers across the country

Question 2

_{Liver Transplants}

Where is the healthy liver obtained?

Answer 2

​From deceased donor who has not suffered liver injury

Question 3

_{Liver Transplants}

How is the healthy liver transported?

Answer 3

in a cooled saline solution

Question 4

_{Liver Transplants}

How long could a healthy liver remain viable in the cooled saline solution prior to transplantation?

Answer 4

Up to 8 hours

This time permits analysis to determine blood and tissue donor-recipient matching

Question 5

_{Liver Transplants}

How long does a liver transplant operation last?

Answer 5

can take 12 hours to complete

Question 6

_{Liver Transplants}

Why do liver transplant operations require large volumes of blood transfusions?

Answer 6

Because the surgical procedure involves cutting and reconnecting multiple major blood vessels

Question 7

_{Liver Transplants}

For which conditions is liver tpx the definitive tx for?

Answer 7

Decompensated cirrhosis

Unresected or unresectable hepatic malignancy

Acute liver failure & other metabolic dz that irreversibly injure the liver

Question 8

_{Liver Transplants}

Why are post liver Tpx pts at high risk of developing atelectasis and small airway closure?

Answer 8

Large, transverse upper abdominal incision

Associate with high intensity pain

Incision is also close to diaphragm

Atelectasis and small airway closure due to not taking deep enough breaths because of pain

Pt should be coached to take deep breaths

Question 9

_{Liver Transplants}

Which vascular structures are affected during liver tpx?

Answer 9

Inferior vena cava

Hepatic veins

Hepatic areteries

Portal veins

Bile duct

Question 10

_{Liver Transplants}

Most pts requiring liver tpx are very sick. Which circumstance usually gets them to the top of the tpx list?

Answer 10

Being hospitalized, and requiring ICU care

Question 11

_{Liver Transplants - Anesthesia Techniques}

True or False: there is a specific anesthetic protocol for liver tpx

Answer 11

False

Question 12

_{Liver Transplants - Anesthesia Techniques}

True or False: it is recommended that each liver transplant facility comes up with a uniform approach to be used initially during transplantation.

Answer 12

True

Question 13

_{Liver Transplants - Anesthesia Techniques}

What’s an appropriate anesthetic technique for liver Tpx?

Answer 13

GETA with RSI

Question 14

_{Liver Transplants - Anesthesia Techniques}

Which drugs would you use for induction and intubation?

Answer 14

Fentanyl

Sodium pentothal/etomidate

Low dose non-depolarizing muscle relaxant (Cis), and

Succinylcholine

Question 15

_{Liver Transplants - Anesthesia Techniques}

Which drugs would you use for maintenance of anesthesia?

Answer 15

Fentanyl

Benzodiazepines

Non-depolarizing muscle relaxant (Cis)

Isoflurane in air/oxygen

Question 16

_{Liver Transplants - Anesthesia Techniques}

Which ventilatory strategy could you use to reduce the risk of air emboli and to prevent atelectasis during liver tpx?

Answer 16

Mechanical ventilation with 5 cmH₂O of PEEP

Question 17

_{Liver Transplants - Anesthesia Techniques}

Why should Nitrous oxide be avoided in liver tpx?

Answer 17

Can lead to bowel distension

Issues with surgical exposure, since bowell and liver share the same area

Question 18

_{Liver Transplants - Preparation}

What are considered standard monitors during liver tpx?

Answer 18

Central line for fluid replacement

^{(insert before or after induction - <u>add two large bore IVs 16g</u>)}

CVP for monitoring fluid status

A-line for beat-to-beat monitoring of heart rate/pressure and multiple blood draws

Foley catheter for urine output

TEE for CO and wall motion monitoring

Question 19

_{Liver Transplants - Preparation}

Why should you have a rapid transfuser available

Answer 19

In case you must administer large amounts of volume/blood in a very short period of time

Question 20

_{Liver Transplants - Preparation}

Why should you have Fluid and body warmers available

Answer 20

The prevent hypothermia

Question 21

_{Liver Transplants - Preparation}

What should you do in anticipation of LARGE blood loss?

Answer 21

Contact Blood Bank

Have large amounts of blood readied

Question 22

_{Liver Transplants - Intraoperatively}

A liver transplant last 12 hours on average, with a range of 4 to 18 hours and is divided into three phases. What are those phases?

Answer 22

Preanhepatic (Dissection)

Anhepatic (No liver connected)

Neohepatic (Revascularization

Question 23

_{Liver Transplants - Intraoperatively - Preanhepatic}

When does the Preanhepatic phase starts? when does it end?

Answer 23

Sarts at incision

Ends when all the vessels are clamped off (Vascular exclusion),

and the native and non functioning liver is taken out (hepatectomy)

Question 24

_{Liver Transplants - Intraoperatively - Preanhepatic}

When the liver is dissected in the Preanhepatic phase, which vessels does it remain attached to only?

Answer 24

Inferior vena cava

Portal vein

Hepatic artery and

Common bile duct

All except hepatic veins

Question 25

_{Liver Transplants - Intraoperatively - Preanhepatic} Which factors in the pt's history could prolong the dissection part of the Preanhepatic phase

Answer 25

Adhesions from previous abdominal surgery

Question 26

_{Liver Transplants - Intraoperatively - Preanhepatic} In the Preanhepatic phase, when would you anticipate large amount of blood loss?

Answer 26

When they start to clamp the different areas and actually cut the vessels Be ready to transfuse

Question 27

_{Liver Transplants - Intraoperatively - Preanhepatic} Which two electrolyte disturbances are commonly associated with liver tpx?

Answer 27

Hyponatremia Hyperkalemia

Question 28

_{Liver Transplants - Intraoperatively - Preanhepatic} Why should you not treat hyponatremia a/w liver tpx too quickly?

Answer 28

...

Question 29

_{Liver Transplants - Intraoperatively - Preanhepatic} Hyperkalemia a/w liver tpx must be treated promptly, but which precautions must be taken?

Answer 29

Remember the steps How do we treat the symptoms How do we treat the disturbance How bad is the hyperkalemia How agressive do we need to be in treating it?

Question 30

_{Liver Transplants - Intraoperatively - Anhepatic} When does the **Anhepatic** phase starts? When does it end?

Answer 30

*_Starts_* at the **occlusion of vascular inflow** to liver being taken out *_Ends_* at **Graft reperfusion**

Question 31

_{Liver Transplants - Intraoperatively - Anhepatic} When is the **inferior vena cava** clamped above and below the liver? Which other major vessels are clamped at the same time?

Answer 31

Once the _dissection is completed_ and the liver is freed **Hepatic artery** and **portal vein** will be clamped at the same time

Question 32

_{Liver Transplants - Intraoperatively - Anhepatic} Once the liver is freed, the inferior vena cava is clamped above and below the liver as well as the hepatic artery and portal vein. What happens next?

Answer 32

The liver is then completely excised and **Veno-venous bypass** may be employed at this time *Donor liver is then anastomosed to recipient patien*t

Question 33

_{Liver Transplants - Intraoperatively - Anhepatic} What's the effect of clamping large vessels (inferior vena cava and portal vein) during the Anhepatic phase of liver tpx on CO and BP

Answer 33

Marked **decreases in CO** and **Hypotension** can be encountered Occurs when inferior vena cava and portal vein are clamped

Question 34

_{Liver Transplants - Intraoperatively - Anhepatic} Which vascular strategy is employed for patients at increased risk during the vena cava clamping?

Answer 34

**Veno-venous bypass**

Question 35

_{Liver Transplants - Intraoperatively - Venovenous Bypass} How does the veno-venous bypass redirects blow flow during liver tpx?

Answer 35

Diverts IVC and portal venous flow to the superior vena cava via the axillary vein

Question 36

_{Liver Transplants - Intraoperatively - Venovenous Bypass} What are the benefits of Venovenous Bypass?

Answer 36

*Can help minimize:* Severe **hypotension** **Intestinal ischemia** Build up of **acid metabolites** and Postoperative **renal dysfunction**

Question 37

_{Liver Transplants - Intraoperatively - Venovenous Bypass} What risks are a/w Venovenous Bypass?

Answer 37

**VAE** **Thromboembolism** Inadvertent **Decannulation**

Question 38

_{Liver Transplants - Intraoperatively - Neohepatic} When does the Neohepatic phase starts? When does it end?

Answer 38

*_Starts_* with the **completion of venous anastomosis** *_Ends_* with when circulation to the new liver is completed and **blood is allowed to enter the new liver**

Question 39

_{Liver Transplants - Intraoperatively - Neohepatic} When is circulation to the new liver allowed?

Answer 39

**Following completion of venous anastomosis** The venous clamps are removed and circulation to the new liver is allowed

Question 40

_{Liver Transplants - Intraoperatively - Neohepatic} Following completion of venous anastomosis the venous clamps are removed and the circulation to the new liver is completed**. Reperfusion syndrome** may occur. What are possible causes of Reperfusion syndrome?

Answer 40

**Cold**, **acidotic**, **hyperkalemic** _solution floading the system_ Could happen quickly and as soon as blood flow is resumed

Question 41

_{Liver Transplants - Intraoperatively - Neohepatic} What potential risks are a/w reperfusion syndrome?

Answer 41

Emboli - Arrhythmia - Cardiac arrest Hypotension

Question 42

_{Liver Transplants - Intraoperatively - Neohepatic} Which drugs could be used to prophylactically treat risks a/w **reperfusion syndrome**?

Answer 42

**CaCl** or **Bicarb** Eliminates huge shift when reperfusion occurs

Question 43

_{Liver Transplants - Intraoperatively - Neohepatic} Following completion of venous anastomosis the venous clamps are removed and the circulation to the new liver is completed. **Ischemia/reperfusion** **injury** is possible. What could be reponsible this?

Answer 43

**Endothelial dysfunction** and **non functioning graft** Happens overtime Could manifest beyond the Neohepatic phase

Question 44

_{Liver Transplants - Intraoperatively - Neohepatic} Following completion of venous anastomosis the venous clamps are removed and the circulation to the new liver is completed. What's the last structure to be connected?

Answer 44

**Common bile duct** of the donor is connected to the recipient

Question 45

_{Liver Transplants - Intraoperatively - Management of liver reperfusion} When it does occur, how is **reperfusion syndrome** managed?

Answer 45

Take steps to bring **potassium** to appropriate level (**\< 4.0**) ^{(Go back and review how to treat Hyperkalemia and associated symptoms)} Replace **calcium** to ensure normal (**\> 5.0**) Correct lactic acidosis (**pH normal**) Appropriate volume infusion to maintain **euvolemia** **Hemoglobin** appropriate (**9 – 10** for most patients) **Epinephrine** *10 mcg/cc* attached to iv ready for administration (*_bolus_*) **Epinephrine** *20 mcg/cc* on baxter pump ready for *_infusion_* *Communication with surgeon – OK for reperfusion*

Question 46

_{Liver Transplants - Intraoperatively - Management of liver reperfusion} In the management of reperfusion syndrome, what should be your target potassium level?

Answer 46

\< 4.0

Question 47

_{Liver Transplants - Intraoperatively - Management of liver reperfusion} In the management of reperfusion syndrome, what should be your target calcium level?

Answer 47

**\> 5.0**

Question 48

_{Liver Transplants - Intraoperatively - Management of liver reperfusion} In the management of reperfusion syndrome, what should be your target **Hemoglobin** level?

Answer 48

**9 – 10** for most patients

Question 49

_{Liver Transplants - Intraoperatively - Management of liver reperfusion} In liver tpx case, when should you start preparing for reperfusion and potential reperfusion syndrome?

Answer 49

During the initial phases of the case