Transplant Flashcards
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
