FRCA Notes

Organ Donation

Resources

  • Organ donation can take place following:
    • Death by neurological criteria i.e. 'successful' brainstem death testing (DBD)
    • Death by circulatory criteria (DCD)
  • Retrieval of organs occurs after death confirmed by 'traditional' cardiorespiratory criteria
  • Can be classified as either:
    • Uncontrolled e.g. dead on arrival in ED or failed resuscitation
    • Controlled e.g. planned withdrawal life-sustaining treatment
  • Is less common than DBD donation

Functional warm ischaemic time

  • The functional (true) warm ischaemic period commences when there is either:
    • A sustained fall in SBP <50mmHg for ≥2min
    • A sustained fall in SpO2 <70%
  • It extends until the onset of cold, in situ perfusion

  • Limiting this period as best possible will help successful donation, as there are stand-down warm ischaemic times for various organs:
    • Liver - 30mins
    • Pancreas - 30mins
    • Lungs - 60mins
    • Kidney - 120mins

  • Although UK legislative change made organ donation an 'opt-out' process, family refusal remains a key contraindication
  • Absolute medical contraindications are:
    • Known or suspected CJD
    • Known HIV

  • There are a host of relative contraindications, including:
    • Advanced age >70yrs
    • Malignancy (active or within 3yrs)
    • Active TB
    • Untreated sepsis

  • There are further organ-specific contraindications

Respiratory

  • Lung - protective ventilatory strategy with 6-8ml/kg tidal volume and optimised PEEP
  • Recruitment manoeuvres
  • Methylprednisolone 15mg/kg

  • Target:
    • PaO2 >10kPa
    • pH >7.25

Cardiovascular

  • Judicious use of fluids to restore circulating volume without fluid overload
  • Vasopressin is the vasoactive drug of choice
    • 0.5 - 4units/hr
    • It treats both hypotension and DI
    • Noradrenaline is a second-line agent

  • Haemodynamic goals:
    • MAP >60 - 80mmHg
    • CVP 4 - 10cmH2O
    • CI >2.1L/min/m2
    • ScvO2 >60%

Metabolic

  • Maintain urine output 0.5 - 2ml/kg/hr
  • Maintain sodium <150mmol/L
  • Treat DI with vasopressin and, sometimes, desmopressin
  • Normoglycaemia (4 - 10mmol/L) with insulin
  • Continue NG feeding
  • Normothermia