Date post: | 05-Dec-2014 |
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Approach to deceased donor transplantation-Donor care
Dr Mayuri TrivediIPGME&R,Kolkata
Institute of Postgraduate Medical Education and Research,Kolkata
Donor action Identification of donor
Screening of donor
Confirmation of donor
Certification of donor
Counseling of family
Maintenance of donor
Concept of Brain stem death
Ancient concept as in hanging or guillotine.
These were anatomical decapitation.
Brain Stem Death in ICU is physiological decapitation
History of brain stem death
1959 – Lyons – France first observed the death of Nervous tissue leading to “coma depasse”.
1968 – Harvard Criteria (EEG was must)
1969 – Minnesota Criteria (No EEG)
1975 – U. K. Code
1994 – THOA 1994 – accepting U. K. Code
Brain stem death Death is scientifically defined as:1. Incapacity to breath spontaneously.2. Incapacity to remain conscious.
When brain stem is irreversibly damaged the cortex no longer has any connection with the rest of the body.
IT IS THE DEATH OF THE PHYSIOLOGICAL CORE OF THE BODY
Hence Brain stem death is death
Brain stem death
Brain death was not discovered for transplantation as the possibility was thought only after 1971
Single largest source of transplantable organs
Diagnosis by clinical bedside means only.
No sophisticated investigation.
3 steps-UK code preconditions exclusions bedside tests
Identification of donor Brain death always occurs in ICU.
Patient must be deeply comatose.
Must be on respirator.
Positive evidence of IC event.
Patients who can be potential donors
Patients with IC bleed Head injury RTA I C vascular thrombosis Depressed fracture Extradural, subdural or intra cerebral haemorrhage Sub arachnoid haemorrhage Brain tumor Brain surgery Anesthesia mishaps Massive brain edema
Where will one suspect a BSD?
The intensive care unit surgeon/physician may suspect brain stem death when the following factors are satisfied:
a. Comatose patient on ventilator in ICU
b. Positive diagnosis of cause of coma (irremediable structural brain damage).
Fulfilling the required preconditions…………
Brain stem death pre conditions
1. Coma lasting for at least 6 hours, or in case of cardiac arrest at least for 24 hrs after restoration of circulation.
2. No abnormal decorticate or decerebrate posture should be present.
3. No epileptic movements should be observed.
4. No spontaneous respiratory movements should be present.
5. All brain stem reflexes should be absent
Brain stem exclusion criterion
1. Absence of coma in the patient.
2. Children below age of 3 years
3. In deeply comatose patients were there is suspicion that coma may be due to:
Depressant drugs Primary Hypothermia(<35 degrees C) Metabolic or endocrine disorders Severe shock Respiratory arrest requiring relaxant or neuromuscular
agent.
4.When diagnosis of the disorder is not fully established.
Bedside test for brain stem reflexes
1. Fixed pupils unresponsive to light.
2. Absent corneal response.
3. Absent oculo-cephalic or doll’s eye movements
4. Absent vestibulo-ocular or caloric response.
5. No motor response within the cranial nerve distribution after adequate stimulation of any body part
6. Absent gag reflex and reflex response to bronchial stimulation by a suction catheter passed down the trachea.
7. Apnea test.
Apnea test Confirmatory test of brain stem death
Performed on the patient on ventilator.
1. Initial pure 100% oxygen given to the patient for a period of 10 mins
2. Followed by 5% CO2 in the oxygen for 5 mins3. Disconnection of the patient from the ventilator for
10mins or more.
However during this period O2 is continued to be delivered at a rate of 6lits/min
Blood collected for blood gases after 10mins when the PaCo2 should have reached >50mmhg with P02 >100mmhg.
Inspite of this if no spontaneous respiration occurs the test is considered positive.
The test has to repeated and confirmed once again after 6-24 hours after the first test.
The patient is then declared ‘Brain Stem Dead’
Practical points for identification
The interval for dose of muscle relaxants becomes longer and longer.
The gag reflex during suction – disappears.
Most of the time the urine bag shows – diluted urine.
Body temperature-poikilothermic
Practical points for identification It is customary to repeat tests to ensure that there
has been no observer error.
Integrity of spinal reflex.
No special investigation like EEG,Angiography,CT scan etc. are required.
BSD is essentially a bedside diagnosis.
Screening of donor All BSD not eligible for organ donation.
Few absolute contraindications.
Potential donor reviewed casewise.
Donor criterion1. Age 2 –70 years.
2. No long standing HT, DM, IV drug abuse, malignancy.
3. No primary organ disease or trauma.
4. Avoid occult sepsis – drowning, burns, more than 7 days indwelling catheter.
5. Negative viral markers.
6. For kidneys – no acute/chronic renal failure, UTI, Creatinine <1.8mg/dl, BUN <20mg/dl, warm ischemia time not > 1hr.
Certification of donor
Brain death committee
Neuro surgeon / neuro physician/Intensivist
Referring RMP
Any specialist from the Institute (pre-selected)
Medical head of the Institution
How confirmation is done?• Confirm the Precondition Exclusion Test for brain stem reflexes Apnea test
All the tests are repeated again between 6-24hrs. Form 8 is filled & signed by all 4 members
Maintainence of potential donor
AIMS of maintainence:
To restore the stability
To maintain or improve the organ functions
To maximise potential for organ donation
To reduce loss of donors prior to organ retrieval
Thus to enhance the successful transplantation
Investigations of the donor
General investigation:1. CBC, BUN, creatinine, electrolytes, ABG, LFT, RBS2. Urine routine, culture3. Blood culture4. Blood group5. X-Ray, ECG, USG6. HBsAg, HIV, HCV, CMV7. 50 cc donor blood for HLA & lymphocyte cross match
with recipient.
Organ specific screening:
Counseling of family To present clear, unambiguous information to the
relatives.
Regular and correct communication.
Care in use of language.
It should be consistent for all multidisciplinary team members.
Councelling to be done to the key person amongst the next to kin of the deceased donor
Who can counsel? Members of the parent unit.
Sister in charge of the parent unit
Medical social workers
Assistant medical officer
Any person authorized by the Institution
Decoupling
The counselor should never make a request to the family about organ donation when the the family has been told of the death of the patient.
Some time must be given to the family to accept the death of their loved one before the topic of organ donation is approached.
Decouple the news of death from the request of organ donation
Stages of Grief Observe the stages of grief in the relatives.
1. Denial2. Anger3. Bargaining4. Depression5. Acceptance
The request for organ donation should be made during the stage of acceptance
Consent Taking the consent of the family.
Consent to be taken from the responsible adult and next to kin of the deceased donor
Consent for organ retrival from relatives is taken on form 6 and form 7.
Maintainence of the donor Standardised , systematic, critical care to increase the quantity & quality of transplantable organs.
Complicated challenge
Optimize physiology prior to retrieval
Minimizes cold ischemia time
Helps more precise co ordination with recipient institution
Maintainence of donor
General care
Organ specific care
General care Clear unambiguous information to relatives.
Change to donor organ goal.
1. Monitor temperature –warming measures if necessary
2. Initiate/ continue enteral feeds3. Tight glycemic control4. Continue antibiotics5. Lung protective ventilation - avoid excess fluid6. Invasive monitoring
CVS ECG monitoring, 12 lead ECG
X-ray chest, arterial line, CVP
Goals :1. Sinus rhythm with pulse rate of 60- 100 beats/min2. CVP <12 mm Hg3. PAP <12 mm Hg4. MAP = 60 – 80 mm Hg5. C I >2.4 l/min /m26. Mixed venous O2 saturation > 60%
Haemodynamic Stability IV fluids 3-5ml/ kg bolus,
Restore euvolume – blood components, albumin, crystalloids. Decrease catecholamine dose
Consideration of vasopressin use
Bradycardia – dobutamine
Arrhythmia – correct electrolyte imbalance, isoproteranol, electrical pacing
Presence of persistent arrythmia –expeditious organ retrieval
Respiratory care Neurogenic pulmonary oedema
X-Ray chest,Peripheral O2 saturation ,ABG
Goals:
1. Peripheral O2 saturation=92 – 95 %2. PEEP 5 cm water3. T V = 6- 8 ml / kg4. Judicious iv fluid, antibiotics5. Corticosteroids6. Diuretics7. Aggressive pulmonary toilet
Renal and electrolytes Hypernatremia, hypokalemia, hypomagnesemia,
hypophosphatemia.
Goals: 1. Urine output 1 – 2 ml / kg/hour2. If urine output > 4ml / kg---D I- vasopressin3. Hypernatraemia – 5% dextrose, plain water RT feeds4. Correct electrolyte levels5. Continue enteral feed
Endocrinology
Polyuria, hyponatraemia
Marginal donors showed adequate organs & improved graft survival with hormonal resuscitation.
GOALS:
1. Treat D I2. Tight glycaemic control-Insulin 1 unit/ hr @ titrate3. Vasopressin 0.5 – 2 ml/ kg / hr4. T 3 - 4 micro gm bolus, 4 mi gm/ hr infusion5. Methylprednisolone
Coagulopathy Thrombocytopenia, hypothermia, release of
plasminogen activator.
Goal:
1. Hb>10 gm %2. INR<23. Platelet count > 50,000/4. Treat only if bleeding
Complications in the donor Hypotension
Cardiac arrhythmias
Electrolyte disturbance
Alteration in pulmonary function
Diabetes insipidus
Hyperglycaemia
Hypothermia
Coagulopathy
Thank you