Organ Donation

This is specific to organ donation in the Australian context.

This covers medical elements of organ donation. Discussing organ donation with family is covered in Organ Donation.

Guiding principles for the process of organ donation in the Australian context arise from two major bodies:

• Legislature
  • Organ donation should be an unconditionally altruistic and non-commercial act
  • Organ donation is an opt-out process
    
• ANZICS
  • No financial benefit should occur to any organisation or person from organ donation
  • Conditional donation should be refused
    Family request that donation only goes to a certain sort of individual (positive condition) or not to a certain sort (negative condition).
  • Directed donation is permissible under certain circumstances
    Donation after death of organs to a named individual.
  • Irrespective of patient’s known wishes, the family should be contacted to discuss donation and donation should not proceed if the family does not agree
  • Tissue donation should be offered to the family of all dying patients in the hospital

There is some discussion as to whether organ donation should be changed to an opt-in model, however international jurisdictions that have done so have not seen an ↑ in donation rates.

Discussing Donation

Organ donation:

• Should not be raised prior to family understanding of death or impending death
• Should not be raised prior to medical consensus for end-of-life care
• Should be discussed with donation staff, prior to discussion with family
• Should be discussed with all families where it is a possibility
  • Any information contained on the organ donor register should also be communicated to family

Suitability

All patients near to the end of life should be referred for consideration of organ donation.

Suitability for organ donation is:

• Highly dynamic
  Varies with recipient/waiting list requirements; i.e. an otherwise ineligible donor may be accepted when an appropriate recipient is in extremis.
• Without fixed criteria
  Diseases commonly (but not exclusively) considered contraindications include:
  • Malignancy
  • Active infection
    • Meningococcal
    • Hepatitis
    • HIV

Information that should be provided to donation coordinator should include:

• Age
• Sex
• Weight
• Height
• Past history
  • Co-morbidities
  • Surgery
  • Medication
  • Alcohol
  • Smoking
  • Illicit drug use
• History of fatal illness
  • Cause
  • Details of cardiac arrest
  • End-organ injury
  • Aspiration
  • Periods of ischaemia
• Current clinical state
  • Organ supports
  • Bloodwork
  • Other investigations

Heart Donation

The heart is highly susceptible to multiple insults that occur during brain death, and therefore the most responsive organ to antemortem interventions.

Standard and Marginal Donor Heart criteria

Parameter	Standard	Marginal
Age (years)	<50	>50
Cardiac History	Nil	Present
Comorbidities	Nil	Hepatitis B Hepatitis C
Echocardiography	Normal	LVEF <50% Major RWMA LVH >13mm
Angiography	Normal Non-occlusive disesease	Occlusive disease
Inotropic support	Low	>0.2μg/kg/min or noradrenaline Or equivalent.
Ischaemic time	<6 hours	>6 hours

Myocardial preservation techniques:

• Cardioplegia
• Ex-vivo heart perfusion

Lung Donation

Standard Donor Lung Criteria

Parameter	Criterion
Age (years)	<60
Smoking (pack-years)	<20
Chest trauma	Nil
Aspiration	Nil
PaO2 (mmHg)	>300mmHg on 100% oxygen
Sputum	Nil
Bronchoscopy	Clear or minimal secretions

Lung preservation techniques:

• Pneumoplegia
  • Cold colloid solution is administered into the PA and PV
  • Flushes out clot
• Ex-vivo lung perfusion
  • ↑ Ischaemic time
  • May improve function of otherwise marginal organs

Donation

Organ donation occurs after determination of patient death, which can be either:

• Brain death
• Circulatory death

Comparison of Recipient Outcomes after Donation

Organ	Brain Death	Circulatory Death
Lung	97% 1-year survival 90% 5-year survival	97% 1-year survival 90% 5-year survival
Heart
Liver	Better than DCD	75% 5-year survival
Pancreas		83% 1-year survival 72% 5-year survival
Kidney	~86% 5-year survival	~86% 5-year survival ↑ Delayed graft function

Donation after Brain Death

Donation after brain death is also referred to as DND, or Donation after Neurological Death.

DBD is only considered in patients with a diagnosis of brain death. DBD is:

Preconditions and determination of brain death are covered in detail under Brain Death.

• The most common path for donors
  75-90% of total donors.
• Generally associated with improved recipient outcomes
  Compared with DCD donation.
• Easier to logistically coordinate
  More predictable than DCD.

Donation after Circulatory Death

DCD is considered when:

• A ventilated patient in whom life-sustaining treatment is to be withdrawn
• Death is likely to occur in a period that permits organ retrieval for transplantation

DCD should:

• Only be considered after consensus reached that active treatment is no longer in the patients interest
  This should include any member of the donation, transplant, or retrieval teams.
• Not influence the administration of sedatives or analgesics
• Be raised with a family if:
  • End of life care is proceeding
  • The family are in favour of organ donation
  • The patient may become brain dead, but has not yet become so

DCD is divided into four categories:

• I: Dead on arrival
• II: CPR ceased
• III: Cardiac arrest expected soon
  Almost all donors in Australia, NZ, UK, and the US.
• IV: Cardiac arrest whilst brain dead

Donation other than class III are uncontrolled, and consequentially more ethically complex. Systems that emphasise utilitarian approaches, or only account for previously expressed wishes of the donor (disregarding family input) have some donations in category I and II.

The nature of DCD donation creates additional complexities:

Acceptable warm ischaemic times vary depending on the organ:

• Liver, pancreas: <30 minutes warm ischaemic time
• Heart: <30 minutes from SBP <90 mmHg to cold perfusion
• Kidneys: <60 minutes functional warm ischaemic time
• Lungs: <90 minute functional warm ischaemic time

• Warm ischaemic time
  Period during which the organs are still warm and consuming oxygen, but hypoperfused and ischaemic. Warm ischaemic time is:
  • The time from circulatory arrest to the time of perfusion with cold preservation solution during retrieval
  • Associated with ↑ complications and ↓ graft function:
    • Delayed graft function
    • Primary graft dysfunction
    • Organ-specific ischaemia
      • Biliary strictures
  • Associated with two other similar terms
    Same underlying physiology but different metrics:
    • Agonal time
      Time from cessation of cardiorespiratory support until circulatory arrest. An agonal time >90 minutes usually precludes donation, and occurs in ~30% of patients.
    • Functional warm ischaemic time
      Time from SBP <50mmHg to the time of cold perfusion.
• Communication
  • Where WCRS occurs
  • Unpredictability of timing of when death occurs
  • Potential failed donation
    • Medically inappropriate
    • Warm ischaemia time exceeded
    • May still donate tissue once death has taken place

Antemortem Interventions

Some patients may receive interventions when:

• The patient is still alive
• The patient is expected to become an organ donor
• The intervention will ↑ organ viability

This is appropriate only if:

• The patient wanted to be an organ donor
• The family has made an informed decision, and consent obtained
• The interventions do not shorten life or compromise care
• Measures are taken to prevent pain or discomfort

Process of Donation

1. Routine referral of all patients who are likely to die for suitability of organ donation
   This includes checking the organ donation register to ascertain the patients wishes.
   
   
2. End-of-life discussion with the family (and the patient, if competent)
   • In DBD, this may be raising the chance of brain death having occurred and the need to perform further testing to confirm this
   • In DCD, this may include discussion of futility of continuing treatment
   • The organ donation nurse should be invited to attend this meeting
     • This allows them to get to know and build rapport with the family
     • They are best introduced as a “specialist nurse” rather than an organ donation specialist if organ donation has not yet been raised
       
       
3. Determination of suitability of organ donation
   By the intensivist and donation team.
   
   
4. Discussion with the family about organ donation
   A separate conversation from the end-of-life conversation, which includes:
   • Donation process
   • Formal consent
   • If relevant, discussing:
     • Coronial consent
     • DCD
       • Risk of a failed donation if agonal time exceeded
       • Determination of death

If DBD, then usually 3 conversations will happen:

1. Initial end-of-life discussion
   Raising brain death testing.
2. Report on outcome of brain death testing
3. Discussion of organ donation
   Separating this conversation from outcomes of brain death testing can be done by introducing a break - “I’d like to meet with you again in half an hour to discuss where we go from here.”

5. Donor assessment
   • Blood
   • Tissue typing
   • Other tests as suitable
     
     
6. Retrieval and transplant team meeting
   
   • Brief discussion of the relevant details of the donors
   • Discussion of the recipients
   • Logistical plan
     
     
7. For DCD, the withdrawal of cardiorespiratory support
   • Negotiation of time and place
     May occur:
     • In ICU:
       • Family can be with the patient at time of death
       • Patient does not have to be moved if agonal time exceeded
       • Rapid transfer to the OR is required following death
         May introduce delays that limit organ donation.
     • In OR:
       • Limit family presence
       • ↑ Speed of retrieval
     • Near the OR
       Hybrid approach of the above.
   • Appropriate prevision of sedation and analgesia
     Should be given by the intensivist, and not by the anaesthetist or transplant team.
   • The surgical team should not be present in the ICU
     
     
8. Organ retrieval
   
   
9. Transfer of the donor to the mortuary
   The donor will “look dead” afterwards; donors generally look the same on transfer to the OR.
   
   
10. Transfer of organs to the transplant centre
    
    
11. Implantation of retrieved organs to the recipient

---

References

1. ANZICS. The Statement on Death and Organ Donation. Edition 4.1. 2021.
2. Bersten, A. D., & Handy, J. M. (2018). Oh’s Intensive Care Manual. Elsevier Gezondheidszorg.