Transplant Flashcards
(36 cards)
1
Q
What are the cold ischemic times for:
heart or lung grafts
livers
kidneys
A
- Heart or lung grafts: less than 6 hours
- livers: 12-24 hours
- Kidneys: up to 72 hours
2
Q
What factors affect wait times for an organ?
A
- 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
Q
What are the indications for transplant?
(table)
A
4
Q
One donor can save ____ lives
A
8
5
Q
Brain death:
concept
how is it declared?
A
- 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
- potentially reversible causes are ruled out
6
Q
What brainstem reflexes are tested and found to be absent in brain death?
A
- 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
Q
How is the apnea test done?
A
- 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
Q
What are some aberrations from brain death?
A
- Hemodynamic instability
- wide swings in hormone levels
- systemic inflammation
- oxidant stress
9
Q
What happens just after brain death?
A
- 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
Q
How is pituitary failure that occurs after autonomic storm treated?
A
- 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
Q
Uncontrolled DCD
Controlled DCD
What is the process?
A
- 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
Q
What are the goals for a donor case?
A
- 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
Q
What meds will you want to have available when setting up your room for a donor case?
A
- Steroids
- N-acetylcysteine
- providone-iodine (per NGT)
- prostaglandin E1
- Broad spectrum antibiotics
- mannitol
- loop diuretics
- heparin
14
Q
What will you be monitoring for during a donor anesthesia case?
What is the reasoning for using volatile anesthetics during a donor case?
A
- 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
Q
Complications during harvest:
hypoxemia
temperature
hypertension
hypotension
A
- 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
Q
Complications during harvest:
dysrhythmias
polyuria
oliguria
A
- 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
Q
Things to know about a living kidney donor
(9)
A
- 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
Q
Things to know about a living liver donor
A
- 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
Q
Anesthetic considerations for a living Right lobe liver donor
A
- 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
Q
What should you consider with pre-op of Kidney transplant recipient?
A
- 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
Q
Anesthetic plan for Kidney transplant
Duration
position
pre-meds
access
A
- 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
Q
What drugs do you want to give if you will be starting aminosuppressant (ATG)?
A
- Pre-meds: tylenol and H2 blocker
- After induction: Benadryl 50 mg and solumedrol 500 mg
23
Q
What are the general goals when providing anesthesia for a kidney transplant?
A
- 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
Q
Anesthesia for Kidney transplant:
Which gas?
Which opioids?
Which NMB?
A
- 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
31
How does ESLD affect the pulmonary system?
* respiratory alkalosis
* reduced diffusing capacity
* pulmonary hypertension
* hypoxemia/hepatopulmonary syndrome- SOB and hypoxia caused by vasodilation in lungs
* reduced right heart function
32
How does ESLD affect the cardiovascular system?
* reduced systemic vascular resistance
* diastolic dysfunction
* prolonged QT interval
* blunted responses to inotropes
* blunted responses to vasopressors
* diabetes
* hyperdynamic circulation
* varices--careful with TEEs!
33
How does ESLD affect the GI system?
* GI bleeding from varices
* ascites
* delayed gastric emptying
* nutritional/metabolic
* muscle wasting and weakness
34
How does ESLD affect the heme system?
* decreased synthesis of clotting factors
* hypersplenism- pancytopenia
* impaired fibrinolytic mechanisms
* risk of massive surgical bleeding
35
How does ESLD affect the renal system?
* Hepatorenal syndrome- renal failure caused by liver failure
* hyponatremia
* impaired renal excretion of drugs
36
How does ESLD affect the endocrine system?
Miscellaneous affects?
* Endocrine system
* Glucose intolerance
* osteoporosis
* fracture susceptibility
* Miscellaneous
* poor skin integrity; pruritus
* increased VD of drugs
* decreased citrate metabolism
* calcium requirement with rapid FFP infusion
