4.3 Heart beating organ donor

Question 1

Pathophysiological changes occurring after brain deaht

Answer 1

1. CVS
2. Resp
3. Endocrine
4. Other

Question 2

1. CVS

Answer 2

1. Initially massive sympathetic surge
   ↑ HR / BP / CO
   Possible myocardial damage
   exacerbated by anaerobic metabolism
2. Manifested arrythmias
   ST changes
   Heart block

Question 3

1. CVS

Answer 3

3. Subsequent loss of sympathetic control
   results in severe hypotension second to vasodilation
4. Hypotension
   exacerbated -
   hypovol + myocardial dysfxn:
   DI / Hyperglycaemia / Osmotic diuresis / ↓T3 production

Question 4

2. Resp

Answer 4

1. Exacerbated by coexisting processes
   Sepsis / Hypoxia / 2nd atelectasis fluid overload contusions
2. Pulmonary Oedema
   ↑ Pulm capil hydrostatic pressure
   LV dysfxn

Question 5

3. Endocrine

Answer 5

1. Anterior and posterior Pit failure
   ↓ADH - DI
   Diuresis / Hypovol / hyperosmolality / hyperNa
2. ↓ T3
   ↓ Low phosphate
   exacerbating CVS comp

Question 6

Endocrine

Answer 6

3. ↓ Cortisol
   Blunted stress response
   ↓insulin secretion -> hyperglycaemia
   ->osmotic diuresis ->metabolic acidosis -> CVS compromise

Question 7

4. Other

Answer 7

1. Hypothalamic failure
   loss of thermoregulation
   hypothermia
2. Exacerbate Peripheral vasodilation
   ↓ BMR + Heat production
3. Coagulopathy
   Release thromboplastin
   other mediators from brain

Question 8

Optimisation and managemnt of distubances in preparation for organ donation

Answer 8

1. CVS
2. Resp
3. Endocrine
4. Other

Question 9

CVS

Answer 9

1. Parameters
Aim CVP 4-10
CI 2.2-2.5L/min/m2
MAP 60-80mmHg
HR 60-100

2. Rx ↓BP w/ fluids initialy
3. Consider CO monitoring
   @ risk of pulmonary fluid overload

Question 10

CVS Mx

Answer 10

4. Pressors / Tropes - fluid resistant hypotension
   Vaso preferred
   maintains cardiac ATP/ ↓hyperosmolality / CO↑

Norad or dopamine if further required

Question 11

Resp

Answer 11

Minimise FiO2 aim >10

LPV
Peep otimisiation
6ml/kg TV
PAP<30

CVP >8 may ↑ A-a gradient

Question 12

Endocrine

Answer 12

1. DI - Rx w/ IV fluids and desmopressin
2. Hyperglycaemia
   Insulin infusion app
3. IV T3
   ↓pressor req
   ↑Cardiac stability
4. High dose methylpred
   ↓inotropic requirements
   ↓Extravascular lung water

Question 13

Other

Answer 13

Maintain normothermia
fluid warmer HME active heating

Correct coagulopathies
FFP Plt Cryo etc