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Flashcards in Transplant Deck (36)
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1

What are the cold ischemic times for:

heart or lung grafts

livers

kidneys

  • Heart or lung grafts: less than 6 hours
  • livers: 12-24 hours
  • Kidneys: up to 72 hours

2

What factors affect wait times for an organ?

  • Blood type- MUST be ABO compatible
  • tissue type
  • height and weight of transplant candidate
  • size of donated organ
  •  medical urgency
  • tyime on the waiting list
  • the distance between the donor's hospital and the potential recipient?? (slide says "donor organ")
  • how many donors there are in the local area over a period of time
  • the transplant center's criteria for accepting organ offers

3

What are the indications for transplant?

(table)

4

One donor can save ____ lives

8

5

Brain death:

concept

how is it declared?

  • Core concept: cessation of cerebral and brain stem function
    • definitions vary state to state
  • Physicians involved in transplant process cannot be involved in declaration
    • potentially reversible causes are ruled out
      • hypothermia (>36 C)
      • hypotension (SBP > 100)
      • drugs
      • toxins
    • Clinical exams
      • apnea test
    • Diagnostics
      • EEG
      • transcranial doppler
      • angiography

6

What brainstem reflexes are tested and found to be absent in brain death?

 

  • absence of pupillary response to a bright light is documented in both eyes
  • absence of ocular movements using oculocephalic testing and oculovestibular reflex testing
    • no movement of eyes for one full minute, both eyes tested separately
  • absence of corneal reflex
    • no eye lid movement when cornea is touched
  • absence of facial muscle movement to noxious stimulus
  • absence of the pharyngeal and tracheal reflexes
    • pharangeal tested by looking for gag or cough with tongue blade or sxn to posterior pharynx
    • trachea tested by passing sxn catheter to level of carina 1 or 2 times and looking for gag/cough

7

How is the apnea test done?

  • 100% FiO2 for 10 minutes
  • Normalize the PaCO2
    • confirmed by ABG
  • Put on T-piece for 7-10 minutes
  • Repeat ABG
  • If PaCO2 > 60 mmHg with absence of spontaneous ventilation

8

What are some aberrations from brain death?

  • Hemodynamic instability
  • wide swings in hormone levels
  • systemic inflammation
  • oxidant stress

9

What happens just after brain death?

  • Adrenergic surges causing ischemia and ischmia-reperfusion injuries
    • transient period of hypotension with increased cardiac index and tissue perfusion that precedes the autonomic storm associated with herniation of the brain
    • bradycardia after herniation is often unresponsive to atropine
    • catecholamine storm is often followed quickly by pituitary failure

10

How is pituitary failure that occurs after autonomic storm treated?

  • hormone therapy (specifics vary widely)
    • triiodothyronine
    • desmopressin to maintain SVR at 800-1,200 dyne/s/cm5 (and for DI)
    • low dose vasopressin also can be used for DI and to reduce catecholamine requirements
    • methylprednisolone
  • Avoid high doses of catecholamines
  • insulin infusion to maintain blood glucose 120-180
  • coagulopathies may require correction

11

Uncontrolled DCD

Controlled DCD

What is the process?

  • Uncontrolled DCD: organ retrieval after a cardiac arrest that is unexpected and from which the patioent cannot or should not be resuscitated
  • Controlled DCD- planned withdrawal of life-sustaining treatments that have been considered to be of no overall benefit to a crtitically ill patient
  • Process:
    • pt is brought to the OR and life support is withdrawn
    • wait up to 1 hour with no support for asystole
    • pt is observed for 2-5 minutes to ensure that the heart does not start beating again spontaneously
    • physician pronounces the pt dead
    • now transplant team enters OR and removes the organs from the now dead pt

12

What are the goals for a donor case?

  • Overall goal is to optimize organ perfusion and oxygenation
  • pressors on hand (vasopressin, epi, NE, ephedrine, neo, dopamine, dobutamine)
    • Keep SBP >100
    • UOP > 1-2 ml/kg/hr
  • Lung protective ventilatory strategies
    • transport to OR with PEEP, may need ICU vent
    • FiO2 100%
  • thromboprophylaxis
  • maintain normothermia- have warming and cooling mechanisms

13

What meds will you want to have available when setting up your room for a donor case?

  • Steroids
  • N-acetylcysteine
  • providone-iodine (per NGT)
  • prostaglandin E1
  • Broad spectrum antibiotics
  • mannitol
  • loop diuretics
  • heparin

14

What will you be monitoring for during a donor anesthesia case?

 

What is the reasoning for using volatile anesthetics during a donor case?

  • CVP monitoring- maintain 6-12 mmHg
    • depends on what organs are being procured: want it higher for kidney and lower for lungs
  • Monitor Na level- maintain < 155
  • PaCO2- maintain 30-35 mmHg
  • Spinal reflexes may be intact
    • use NMB
    • Volatile anesthetics (Iso 0.4)
      • blunt spinal reflexes
      • reduce andrenergic storm
      • provide ischemic preconditioning to vital organs
    • opioids will also help reduce response to stimulation

15

Complications during harvest:

hypoxemia

temperature

hypertension

hypotension

  • Hypoxemia- atelectasis, pulmonary edema, aspiration, PNA
    • FiO2 and MV to maintain a PaO2 <100, PaCO2 = ~35 and pH WNL
    • follow ABG q 30 min
    • avoid high peep to preserve CO and avoid barotrauma
    • Avoid high FiO2 in potential lung donors to minimize O2 toxicity
  • Unable to regulate temp- actively warm pt!
  • Hypertension - transiently accompanies brain death 
    • reflex HTN response to surgical stimulation
    • tx with short acting agents (nitroprusside, esmolol)
  • Hypotension- follows the transient HTN d/t hypovolemia and poor vasomotor control
    • tx with crystalloid, colloid, and blood broducts
    • keep Hct >30%
    • use pressors PRN

16

Complications during harvest:

dysrhythmias

polyuria

oliguria

  • Dysrhythmias- d/t electrolyte imbalance, hypothermia, increased ICP, hypoxemia and acidosis, and derangement of brainstem cardiovascular control centers
    • antiarrhythmics as normal
    • bradycardia is resistant to atropine, have pacing available
  • Polyuria- d/t volume overload, osmotic diuresis, or DI from derangement of the HPA
    • maintain IV infusion of vasopressin or desmopressin
    • discontinue 1 hr before aortic cross-clamping to minimize the risk of ischemic injury
  • Oliguria
    • treat with volume; good diuresis preferred if kidneys taken
    • use pressors
    • fluid and pressors not working? mannitol and/or furosemide

17

Things to know about a living kidney donor

(9)

  • Donor should be healthy, no renal disease, history of proteinuria or stones
  • Often done laparoscopically (hand assisted)
  • 2.4% of donors have anesthetic/surgical complications
  • Good ERAS candidate: CHO load, TAP block, multi-modal pain
  • insufflation decreases renal blood flow- compensate with fluids to prevent renal injury
  • Nitrous contraindicated b/c it impairs surgical visualization
  • Not common to place CVL- CVP unreliable with lap retrieval in lateral position
  • extubate in OR
  • post op pain control (epidural, PCA)

18

Things to know about a living liver donor

  • Healthy
  • Left lobe donations (segments II and III) usually done as parent to child donation- recipient < 15 kg
    • major procedure but lower risk than right lobe
  • Right hepatectomy for adult to adult transplantation
    • major procedure with significant risk
    • residual liver volume must be >35% of original volume
    • early death among donors is 1.7 out of 1,000
    • 1/3 of donors experience complications:
      • air embolism
      • atelectasis
      • PNA
      • resp depression
      • biliary tract damage

19

Anesthetic considerations for a living Right lobe liver donor

  • Significant hypotension with cross-clamping hepatic pedicle
    • debate over volume loading (prevent renal compromise) vs volume restriction (decreased blood loss)
    • vasopressin and norepi will augment physiologic levels to compensate
  • Right hepatectomy usually done open
  • CVL +/-, surgeon preference
  • EBL < 1 L, good case to use cell saver
  • avoid hypothermia
  • plan for OR extubation
  • pain control (epidural, TAP catheters, PCA)
  • postop:
    • hypophosphatemia is common
    • liver function tests including INR are abnormal- uually return to baseline w/in 3 months-1 yr
    • some donors have chronic low platelets

20

What should you consider with pre-op of Kidney transplant recipient?

  • b/c kidney cold ischemia time is longer, there is often time for dialysis before surgery
  • Pts often have diabetes mellitus and/or hypertension
  • Increased risk of CAD and congestive heart failure
    • frequently hyperdynamic (could be fluid overloaded or dry if they just had dialysis)
  • Evaluate electrolyte and acid-base abnormalities, anemia, and platelet dysfunction (uremic)
  • PFTs are particularly important in type 1 diabetics
    • common issues with reduced lung volumes and diffusing capacity

21

Anesthetic plan for Kidney transplant

Duration

position

pre-meds

access

  • Usually GETA
    • epidural/spinal not best option d/t uremic plt dysfunction and residual heparin after dialysis
  • Duration: about 3 hours
  • Position: supine- kidney placed in R iliac fossa
  • Pre-meds: tylenol, H2 blocker to prevent reaction to immunosupressant; versed
  • RSI: d/t diabetes, gastroparesis, uremia
  • Expect difficult IV, CVL access- will need CVP
  • Foley, NGT

22

What drugs do you want to give if you will be starting aminosuppressant (ATG)?

  • Pre-meds: tylenol and H2 blocker
  • After induction: Benadryl 50 mg and solumedrol 500 mg

23

What are the general goals when providing anesthesia for a kidney transplant?

  • Goal: preserve renal blood flow
    • volume loading and avoidance of pressors
    • usually get ~3L in to volume load before new kidney is in
      • switch to albumin after first L of crystalloid
      • monitor CVP as a guide
  • Goal:
    • keep BP > 90 mmHg
    • MAP >60 mmHg
    • CVP > 10 mmHg
  • *Blood products not usually needed, but have available.

24

Anesthesia for Kidney transplant:

Which gas?

Which opioids?

Which NMB?

  • Any inhalational agent--does not affect outcome
  • Avoid Morphine and demerol--Fentanyl is usually used
  • Cisatracurium may be NDMB of choice- reliable to get twitches back within 25 minutes  if temp is WNL
    • Vec and Roc take long time to metabolize d/t kidney function
    • Atracurium has histamine release we want to avoid
    • Transplant surgeons really like pts relaxed

25

Anesthesia for Kidney transplant:

UOP

Plan to extubate?

Post op pain control?

  • Monitor UOP after unclamping
  • Anticipate administration of lasix and mannitol around time of first anastomosis
  • monitor glucose and electrolytes throughout
  • Plan to extubate
    • evaluate closely for fluid overload to make decision to extubate
      • listen to lungs! Pt may be tachypnic d/t fluid overload, NOT PAIN
  • Post op pain control?- pain expected to be severe
    • consider TAP blocks, combo ilioinguinal-iliohypogastric and intercostal nerve blocks
    • PCA

26

What medications are contraindicated in kidney transplant patient?

  • NSAIDS
  • Cox-2 inhibitors

27

What are possible post-op Kidney transplant complications?

  • Ureteral obstruction and fistulae
  • vascular thromboses
  • lymphoceles
  • wound complications
  • bleeding

28

Considerations for pancreas transplant

  • Usually comes with a Kidney too, so all kidney info applies to those pts
  • All pts get art line because kidney/pancrease transplant is very long and we check blood sugars every 30 minutes after pancreas is in
    • goal 120-180; don't want it too low b/c when the pancrease goes in their bs will tank
  • ICU post-op

29

Blood flow to the liver

  • 25%-30% of the CO goes to liver
  • dual blood supply
    • hepatic artery provides 25% of blood with 50% of O2 delivery
    • Portal vein provides 75% of blood with 50% of O2 delivery

30

How does ESLD affect the CNS?

  • encephalopathy 
  • fatigue
  • BBB disruption and intracranial hypertension in acute liver failure