Transplantation chap 38 ppt Flashcards
What are the different phases of getting a transplant? Describe each.
- Pre-transplant: the donor and recipient are evaluated and educated
- Transplant: the acute course/hospitalization, the actual transplant
- Post-transplant: immunosuppressive meds are taken for life, complications of surgery include infection and rejection, the patient needs to be aware that noncompliance to medication is life threatening and lifestyle changes need to be made
What are the different types of grafts?
- Autograft: self-graft; transferring tissue from one part of your body to another
- Xenograft: a graft from a different species
- Allograft: a graft from one person to another
Who can be a donor?
Someone either living or deceased. If decreased the person must be either brain dead or their heart has no longer beat.
Define brain death.
The uniform determination of death act (UDDA) defines death in two ways: total irreversible failure of cardiorespiratory system or irreversible loss of all brain functions including brain stem and neocortex.
What are the qualifications of brain death?
Four diagnostic criteria must be met before clinical diagnosis of brain death can be made: clinical or neurologic imaging evidence of acute CNS catastrophe that is compatible with the clinical diagnosis of brain death, exclusion of complicating medical conditions, no drug intoxication or poisoning, core temp >32 degrees C
What must the physician determine in order to diagnose brain death?
The person must be in an unresponsive coma, absence of brainstem reflexes, absence of respiratory drive after co2 challenge (apnea test). Physician also must insure that brain death is irreversible by: determining the cause of coma, excluding mimicking conditions, and observation of the patient for a period of time to exclude possibility of recovery
What are some confirmatory tests in order to diagnose brain death?
CT angiogram (four vessel angiogram to determine if intracerebral filling is absent), MRI, MRA, EEG (to determine the absence of electrical activity for > 30 min), nuclear brain scan (to determine absence of isotope uptake in the brain parenchyma aka no blood through brain but through nose area; empty light bulb scan)
What are that qualifications that a donor must meet in order to donate? How do we manage the tissues/organs to be donated?
The donor must have a body that is dying and shutting down aeb hemodynamic instability, loss of thermoregulation, fluid and electrolyte abnormalities, pulmonary dysfunction, hematopoietic dysfunction, loss of endocrine function. Be sure to maintain oxygenation and perfusion of organs after brain death.
At what lvls do we expect MAP, CVP, ejection fraction, ABG, Pao2, Na, glucose, UO, and number of vasopressors for a patient planning to donate?
MAP: 60-100 mmHg, CVP: 4-12 mmHg, ejection fraction: >50%, ABG: 7.35-7.45, Pao2: 300 or greater, Na: 155 or less, glucose: 180 or less, UO: greater than 0.5/mg/kg/hr, number of vasopressors: 1 or less used
What are functional instabilities or organ donor management?
- Hemodynamic instabilities – the goal is to keep MAP between 60-100 mmHg, keep ejection fraction >50%, and minimize use of vasopressors. Accomplish this by aggressive fluid resuscitation, administration of levothyroxine (T4), and IV catecholamine therapy.
- Thermoregulatory instabilities – the goal is to maintain body temperature at 96-100 F. Accomplish this by giving the pt a warming blanket (if cold) or a cooling blanket (if hot).
- Renal/fluid electrolytes instabilities – the goal is to keep UO >0.5/mg/kg/hr, serum Cr 100 mmHg, and PaO2/FiO2 ratio >300. Accomplish this my mechanical ventilation, PEEP, high frequency percussive ventilation
- Hematopoietic instabilities – the goal is to maintain adequate hematopoietic status. Accomplish this by monitoring Hbg/Hct, PT/PTT/INR, replace blood as necessary, fresh frozen plasma, cryoprecipitate, and factor VII
- Endocrine instabilities – the goal is to maintain adequate hormone levels and serum glucose
What information do you need to get from a donor in order to be a potential qualify for donation?
Patient’s name, age, sex, race, cause of brain injury, height and weight, current GCS, past medical and social history, lab data: serum electrolytes, BUN, creatinine, AST, ALT, alkaline phosphorus, WBC, Hg, Hct, hemodynamic status: BP, MAP, HR, o2 stats, UO, current inotropic drugs if indicated, brain death testing used, DNR status
Define organ procurement. What steps need to be taken for organ procurement? What happens during surgery? How is the organ managed before surgery?
Organ procurement is basically the whole process of trying to find an organ for a recipient. We need to determine if the donor is suitable for organ donation by determining: type of death, health status, age, weight, medical and social history. We also need to obtain informed consent, perform various tests on the donor, and keep in mind that priority is given to recipients in local area then regional then national. During surgery each recovery team is present but the donor’s attending cannot be part of the recovery team. Be sure to preserve the organ by keeping it cold in ice and transport to destination site.
How do we determine if the donor and recipient are compatible?
- Tissue typing: identify the histocompatibility (HLA) antigens of both donor and recipient (or the degree to which the two tissue match)
- Crossmatching: tests the recipient for antidonor antibodies
- ABO testing: identifies the blood group of donor and recipient, type O is universal donor and type AB is universal recipient
How do we determine the type of transplant needed?
Evaluate the recipients: end organ disease status to see if maximum medical therapy has failed or was ineffective, nutritional, psychosocial, and financial status, placement on UNOS waiting list, wait time, transplant resources and support
What are some post-transplant complications?
- During surgery: vascular thrombosis, bleeding anastomosis leakage
- Graft rejection: Hyperacute, acute, chronic
- Immunosuppressant problems: infection, organ dysfunction, secondary malignancy, endocrine dysfunction
What are various ways the recipient gets an infection after surgery is completed? Use CREDIT acronym.
- C: community acquired
- R: reactivation of previous infection
- E: epidemiologic exposure
- D: donor derived infections
- I: iatrogenic (getting sick from hospital procedures)
- T: travel
Name immunosuppressive medications the recipient can use. Major side effects?
The main immunosuppressive med the pt is going to use falls under the category of Calcineurin inhibitors (inhibit t & b cells). These include: cyclosporine, tacrolimus, sirolimus which are the most effective ones. These are often used in combination. Major SEs: infection, renal toxicity, cancer. The pt can also receive steroids.
Describe characteristics of tacrolimus. Major and minor SEs? How is dosing based?
Also known as FK506, progaf. Is the most powerful immunosuppressant but can lead to life threatening renal toxicity. Other SEs include tremors, HA, HTN. The dosing is based on lvls & target range.
Describe characteristics of cyclosporine. Also known as? Is it compatible or not?
Also known as Sandimmue/neural. Has may incompatibilities.
Describe characteristics of sirolimus. Also known as? Commonly used with? Newer uses? Approved w/?
Also known as Rapamuine, Rapamycin. This drug is generally used in combo w/ tacrolimus and cyclosporine. Is being used experimentally in newer settings like chronic graft vs host disease. Is approved for renal transplants.
Describe characteristics of glucocorticoids (steroids). Where is it made? What does it treat? Major side effects?
Produced by the adrenal glands. We can use prednisone to treat acute and chronic rejection (doses are large). Major SEs: DM, bone disorders, steroid myopathy, cushing like changes, skin changes, infection
What are some other immunosuppressants that can be used other than the traditional ones? Complication?
- Cellcept (MMF) which is a cytotoxic agent: this drug can be used for organ rejection prophylaxis in combination w/ steroids and cyclosporine
- Antibodies: monoclonal and polyclonal which target lymphocytes responsible for the immune rejection reaction. These are made from foreign proteins which can trigger serum sickness or anaphylaxis which can cause symptoms such as fever, chills, rigors, rash. Ex of antibody: ATG
Describe characteristics of hematopoietic stem cell transplant. What is it? When is it used? What is a complication?
Stem cells are undifferentiated cells which means that they can turn into any cell. Also known as CD34 or the “mother” cell. When transplanted can restore normal bone marrow function in pts w/ heme malignancy or bone marrow failure. Can be used w/ pts who take high doses of chemo or when doing a “mini” transplant (watch out for graft vs leukemia effect in which recipient’s leukemia clone are destroyed by donor’s lymphocytes).
Where can we get stem cells from?
Bone marrow, peripheral blood, umbilical cord blood
