Our living liver donor - evaluation and selection: Understanding the process.
Safety for the living liver donor is the foundation principle for us to accept a liver donor. It is of paramount importance to us and this paradigm reflects our evaluation and acceptance. At the same time, we look for features that allow us to match the donated segment of the liver to the metabolic (the energy requirements) of the patient.
Broadly, we use the following principles for defining an acceptable candidate,
Stage 3 Investigations: Investigations at this stage to answer specific questions in relation to donor safety and suitability of donation. The specific questions and the tests evaluated
Does the donor have any risk of forming blood clots due to undetected clotting factor diseases? To answer this, we evaluate the following: Protein C, Protein S, Anti Thrombin 3, Factor V Leiden. All the above tests are blood tests and results will be available in 5 days.
Does the donor have any infectious diseases that can be transmitted to the recipient by the transplant? We screen for the following problems: CMV IgG and IgM, EBV IgG and IgM, HSV IgG,Varicella IgG. These investigations will vary between centres depending on the prevalence of infectious diseases in the community. All the above tests are blood tests and results will be available in 5 days.
Is the donor anatomy suitable for the donation? Our standard imaging evaluation is CT triphasic study with volumetry assessment and 3D reconstruction of vascular structures. We also do an MRCP to study the biliary anatomy. We do insist that the radiological study of the liver is done in our own radiology lab to ensure quality standards. In case of doubts that arise, we will suggest further imaging. A preliminary result about the anatomical suitability will be available in 24 hours, but detailed reporting will take 48 hours.
Stage 4 Investigations: These tests are immunological tests which will allow us key information that may be needed in certain types of rejection. Stage 4 tests do not affect donation and will be done as the last step prior to donation surgery. The tests that we do are HLA matching, Cross matching-CDC / flow cytometry and DSA.
Occasionally, we might have further concerns about the donor and may need additional tests to ensure donor safety and suitability and they will be decided on case by case basis. But these are rare instances and it is difficult to draw a general picture for the reader.
Broadly, we use the following principles for defining an acceptable candidate,
- Primary criteria - Age and blood group must be acceptable for donation
- Minimal or no co-morbid illness
- No transmissible illness, either infections or cancers
- Acceptable graft volume and remnant volume
- Acceptable anatomy for surgeons and the recipient
- No psychosocial issues
- Good family support system
- Blood group - should be the same as the recipient, if they have tested this previously. If you do not have a blood group, we can do the test as an out patient prior to seeing the doctor.
- Height and weight to assess the BMI will be checked. We accept BMI > 18 and < 28, for Indian patients.
A counselling session with the surgeon occurs at following the basic evaluation. This lasts 15 to 30 minutes and allows the donor to ask questions regarding the procedure and clarify all his or her doubts.
We currently prefer candidates with no co-morbidities and no surgery, but can be evaluated on an individual basis by the surgical and medical team.
The evaluation process for the donor lasts 3 days to 5 days and will be done as an outpatient. All the results will be presented to both the medical and the surgical team and the decision to accept or reject the donor will be confirmed by the selection committee meeting every Wednesday and the results will be informed to the donor on the same day. We do not pass any information or discuss any information with the recipient, however close they may be, without the express consent of the donor.
It is possible that our team may repeat some of the lab reports that are done outside, especially if it has been more than a month since the time of the evaluation. Also, lab tests that provide information in other languages cannot be acceptable in transplant and we would like to have standardised evaluation in a well controlled, lab of international quality like the one we work with. This is more so about blood grouping / typing where it is our policy to accept only labs from our own hospital.
The donor investigations after the preliminary tests are as follows:
Stage 2 Investigations: are done to answer the following questions.
Is the liver suitable for donation? This will mean that the liver has no underlying disease and the blood flow to and from the liver is okay. To assess this, we do the following tests: USG abdomen with doppler, Viral markers (Anti HBc Total, Anti HBs,Anti HAV IgG), Mineral deposition diseases (Ceruloplasmin, Iron studies), Autoimmune liver diseases (ANA, AMA, SMA, Anti LKM) and A1AT deficiency.
Is there any transmissible infection? We do some of the viral infections that would contraindicate a donation at this point and others in stage 3 investigations to reduce cost. HIV, HCV and HBV NAT, VDRL are the tests that are done in this stage.
Is there any cancer in the donor and have they completed age appropriate cancer screening? We follow the ACS and AASLD guidelines for cancer screening. The tests that are usually done are CA 19-9 , CEA, AFP, PSA in males > 40 years of age, Mammogram in women > 40 years and Pap smear for women > 20 years or married or sexually active females.
We exclude pregnancy in female donors.
We screen donors for vitamin deficiencies routinely: Vit D, Vit B12,Folate.
The risk to the donor comes from undetected illness in other systems. So general investigations to screen them are done. Complete blood counts, Kidney function tests, ESR, Clotting assessment tests (BT,CT, PT, INR, APTT), Urine examination, Stool tests, Diabetes and thyroid disease screening are the tests that are done in this risk assesment.
The fitness of the lung and the heart is tested by looking at the Chest X ray and pulmonary function tests and ECG, Echocardiogram and the treadmill test.
At the end of this stage of testing, a team of four specialists will assess the donor independently: Psychiatrist, Cardiologist, Chest physician and anaesthesiologist. Their opinion on the safety of the donor will be given appropriate weightage to accepting donation.
We currently prefer candidates with no co-morbidities and no surgery, but can be evaluated on an individual basis by the surgical and medical team.
The evaluation process for the donor lasts 3 days to 5 days and will be done as an outpatient. All the results will be presented to both the medical and the surgical team and the decision to accept or reject the donor will be confirmed by the selection committee meeting every Wednesday and the results will be informed to the donor on the same day. We do not pass any information or discuss any information with the recipient, however close they may be, without the express consent of the donor.
It is possible that our team may repeat some of the lab reports that are done outside, especially if it has been more than a month since the time of the evaluation. Also, lab tests that provide information in other languages cannot be acceptable in transplant and we would like to have standardised evaluation in a well controlled, lab of international quality like the one we work with. This is more so about blood grouping / typing where it is our policy to accept only labs from our own hospital.
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| Basic blood investigations in the potential liver donor. If anyone in the family is willing to be a donor, the family or the donor themselves can do these investigations and report to the transplant team. |
The donor investigations after the preliminary tests are as follows:
Stage 2 Investigations: are done to answer the following questions.
Is the liver suitable for donation? This will mean that the liver has no underlying disease and the blood flow to and from the liver is okay. To assess this, we do the following tests: USG abdomen with doppler, Viral markers (Anti HBc Total, Anti HBs,Anti HAV IgG), Mineral deposition diseases (Ceruloplasmin, Iron studies), Autoimmune liver diseases (ANA, AMA, SMA, Anti LKM) and A1AT deficiency.
Is there any transmissible infection? We do some of the viral infections that would contraindicate a donation at this point and others in stage 3 investigations to reduce cost. HIV, HCV and HBV NAT, VDRL are the tests that are done in this stage.
Is there any cancer in the donor and have they completed age appropriate cancer screening? We follow the ACS and AASLD guidelines for cancer screening. The tests that are usually done are CA 19-9 , CEA, AFP, PSA in males > 40 years of age, Mammogram in women > 40 years and Pap smear for women > 20 years or married or sexually active females.
We exclude pregnancy in female donors.
We screen donors for vitamin deficiencies routinely: Vit D, Vit B12,Folate.
The risk to the donor comes from undetected illness in other systems. So general investigations to screen them are done. Complete blood counts, Kidney function tests, ESR, Clotting assessment tests (BT,CT, PT, INR, APTT), Urine examination, Stool tests, Diabetes and thyroid disease screening are the tests that are done in this risk assesment.
The fitness of the lung and the heart is tested by looking at the Chest X ray and pulmonary function tests and ECG, Echocardiogram and the treadmill test.
At the end of this stage of testing, a team of four specialists will assess the donor independently: Psychiatrist, Cardiologist, Chest physician and anaesthesiologist. Their opinion on the safety of the donor will be given appropriate weightage to accepting donation.
Stage 3 Investigations: Investigations at this stage to answer specific questions in relation to donor safety and suitability of donation. The specific questions and the tests evaluated
Does the donor have any risk of forming blood clots due to undetected clotting factor diseases? To answer this, we evaluate the following: Protein C, Protein S, Anti Thrombin 3, Factor V Leiden. All the above tests are blood tests and results will be available in 5 days.
Does the donor have any infectious diseases that can be transmitted to the recipient by the transplant? We screen for the following problems: CMV IgG and IgM, EBV IgG and IgM, HSV IgG,Varicella IgG. These investigations will vary between centres depending on the prevalence of infectious diseases in the community. All the above tests are blood tests and results will be available in 5 days.
Is the donor anatomy suitable for the donation? Our standard imaging evaluation is CT triphasic study with volumetry assessment and 3D reconstruction of vascular structures. We also do an MRCP to study the biliary anatomy. We do insist that the radiological study of the liver is done in our own radiology lab to ensure quality standards. In case of doubts that arise, we will suggest further imaging. A preliminary result about the anatomical suitability will be available in 24 hours, but detailed reporting will take 48 hours.
Stage 4 Investigations: These tests are immunological tests which will allow us key information that may be needed in certain types of rejection. Stage 4 tests do not affect donation and will be done as the last step prior to donation surgery. The tests that we do are HLA matching, Cross matching-CDC / flow cytometry and DSA.
Occasionally, we might have further concerns about the donor and may need additional tests to ensure donor safety and suitability and they will be decided on case by case basis. But these are rare instances and it is difficult to draw a general picture for the reader.
