8. Transplants- Exam 2 Flashcards
Perfusion is involved in what 3 types of transplants:
Heart Transplants
Lung Transplants
Liver Transplants
–Can be performed individually or in combination-Often along with a kidney
1905 – Carrel and Guthrie=
Described first heterotopic transplant of a donor heart into the neck of a dog
–NOT a functional model
Carrel and Guthrie – University of Chicago=
Created innovative surgical technique for vascular anastomoses
when did Carrel win the nobel? in what?
Carrel won the Nobel Prize in Medicine and Physiology in 1912 for his work in this area
1933 – Mann, et al. at Mayo Clinic=
Heterotopic transplant with circulatory unloading of the RV
- -WORKING model
- -“some biologic factor which is probably identical to that which prevents survival of other homotransplanted tissues and organs”
1960 – Lower and Shumway=
Orthotopic heart transplant in dogs with CPB and topical hypothermia for donor heart preservation
1960s – what was introduced? what happened shortly after that?
Pharmacologic immunosuppression introduced.
–Not long after – First clinical transplantation occurred=Kidney
1967 - what occured?
First human heart transplant was performed in South Africa
–Followed shortly by Shumway and colleagues at Stanford in 1968
1970s- what was discontinued
Most centers discontinued doing transplants
1980s- what was introduced?
cyclosporine-based immunosuppression introduced
–Interest in transplantation re-emerged
Patient Selection consists of?
Patients have to be in end stage CHF
Must be able to benefit from a transplant
how do you classify end stage CHF
- NYHA function class III or IV
- Symptomatic refractory to management with medications, electrophysiology devices (pacemakers/AICD) and surgical intervention.
- LVEF < 35%
- Cardiogenic shock= Acute MI / Acute Myocarditis
- Ischemic heart disease
candidates should be less than what age
Should be less than 65 years old
- -Can be done in older patients
- -Physiologic age is a better indicator than chronologic age!!!
Contraindications: what is Irreversible pulmonary hypertension and what might it cause
Pulmonary htn is a complication of CHF with elevated LVEDP.
- -Can create irreversible changes to pulmonary vasculature
- -Could cause RV failure in new organ
- -PA systolic above 50-60mmHg is not good!
what can you give to prevent pulmonary HTN
inhaled nitric oxide
why are Active Infection and malignancy contraindications and if present what needs to occur before they can be a candidate again
Infections are exacerbated by immunosuppression required after transplantation.
- -Need to be fever free for 72 hours
- -Normal white cell count
- -Negative blood cultures
what diseases are usually contraindicated and which one is becoming more acceptable
Hepatitis B, C, HIV not usually done
–HIV is becoming more acceptable to transplant due to improvement in drug therapy.
what diseases are OK to transplant with
Non-melanoma cutaneous cancers
primary cardiac tumors restricted to the heart
low grade prostate cancers
why is obesity a contraindication? what should your BSA be below?
Impacts infection rates, wound healing, and have an increased incidence of acute rejection.
–BMI less than 30 kg/m2
why is diabetes a contraindication
- Relative contraindication
- Control of blood sugars on steroids and immunosuppressant’s
- Wound healing
what are 6 other relative contraindications
Pulmonary Fibrosis Emphysema Hepatic and renal dysfunction Cerebral vascular disease Peripheral vascular disease
why are psycosocial disorders a contraindication
Substance abuse (tobacco, alcohol)
Compliance with medications
Frequency of social support
when organ matching, what 5 criteria do you look at
- ABO Blood Compatibility
- Overall body size= Must be within 20% of body weight
- HLA Cross match= Some patients are sensitized to antigens due to pregnancy, prior transplant, or blood transfusion.
- Priority on UNOS Registry
- Geographic distance from donor
what are the wait listing criteria
- Status code and time within the status code
2. Highest medical urgency and lowest short term survival are assigned higher codes.
how does wait listing work
- Offered to local status 1 patients first, Status 1A before Status 1B.
- No match? Offered to Status 1 patients within 500 mile radius.
- No match? Offered to Status 2 local patients.
- Repeat at 1000 mile radius, and 1500 mile radius
what is the technique for procurement- donor
- Donor heart is arrested with a cpg / preservation solution.
- Atria are transected at the midatrial level
- Leave multiple pulmonary venous connections to the LA intact.
- Transect the aorta and PA just above the semilunar valves
- Heart is cooled topically.
- Ischemic time – 3-4 hours!! (can do up to 5-6 hours – not ideal!!)
what is the ischemic time for procurement
3-4 hours!! (can do up to 5-6 hours – not ideal!!)
what is the technique for Bi-Atrial - recipient
Re-anastomosis of midatrial level
- Start at atrial septum
- Generous “cuff” of donor RA, so SA node will be included in transplant
- Great vessels connected above the Semilunar valves
what is the technique for Bi-Caval - recipient
Leave donor atria in tact and make the anastomosis at the SVC and IVC and Pulmonary Veins
- Notice less distortion of the aortic valve
- Improved atrial and ventricular function
- Less AI
- Less arrhythmias/ heart block.
what is the post-op course for the recipient
Same as a normal cardiac case
- Patient will be on immunosuppression drugs
- Will require pacing for a few days
- Takes 2-3 days for the SA node to come back and “reset”
how long does it take for the SA node to come back and “reset”
2-3 days
Physiology of Transplanted Heart= (6)
- Completely denervated
- Faster resting heart rate (95-100 beats per min)
- Slower to increase HR in response to exercise
- Slower to recover after exercise
- No angina with ischemia
- Don’t respond to drugs that work via the parasympathetic pathway
the physiology of the transplanted heart having a faster resting heart rate (95-100 beats per min) means what
Intrinsic rate of SA node
No parasympathetic down regulation
the physiology of the transplanted heart having No angina with ischemia means what
Will have silent MIs. Will present with CHF, Silent MI or Sudden death
- Donor heart is located
- Patient will be in the room about the time the harvest team is at the donor site.
- Harvest team will be able to view the heart. Once they view a TEE and visualize – will call the OR.
- Patient will be induced.
- Harvest team will call saying heart is out.
- -What do you do?
Write down donor cross clamp time. This is the start of the ischemic period of the donor organ.
- Patient will be draped. If it’s a redo, incision will be made with the “heart out” call.
- -where is the incision? what do you do if its a re-do?
Median sternotomy
If it’s a redo, you’ll go on Fem-fem.
- Heart is in the room
- -what do you do?
Go on bypass. Usually drift, or cool to about 32*C. Cross clamp almost immediately
- Recipient’s diseased heart is removed
- -what may or may not be given?
Cardioplegia not usually given
- Surgeon will go to the back table to trim the donor heart.
- Donor heart is moved into position in the chest.
- Donor heart is sewn in.
- Rewarm
- Sutures complete
- -what is now given?
Some institutions give a “hot shot” type dose of “cardioplegia”. Use Glutamate Aspartate Solution. Full of nutrients for that ischemic heart. Other places don’t.
after the sutures are complete, what are the remaining 5 steps
- Cross Clamp off
- Pacing wires placed
- Fill up heart
- Wean from CPB.
- Close
Heart in a Box= year? what is it?
May 2007 – First beating heart transplant
Heart in a Box is maintained at what temp? what is it hooked up to? how does it work
Maintained at normal body temperature
hooked up to the Transmedics Organ Care System
Beats with warm, oxygenated blood inside a sterile box
describe 3 benefits of the Heart in a Box
- Prolongs time between removal of the heart and transplantation.
- Decreases injury while ischemic.
- Can allow for the right patient to get the right organ, despite distance
First human lung transplant was done over __ years ago at the University of Mississippi
35 years
Patient with severe emphysema and carcinoma of L. Bronchus
Died 18 days later of renal failure
in 1986 what did Stanford and Toronto do
Stanford - First heart-lung transplant
Toronto – First single lung transplant
how many lung transplants are performed annually
more than 1000
Wait time for a single lung is more than __ months, and __ months for a double lung
24 months
36 months
what are indications for a lung transplant
- Irreversible, progressively disabling, end-stage pulmonary disease
- Usually life expectancy is less than 18 months
- Oxygen dependent
- Exercise intolerance
- Less than 65 years old
- Poor quality of life
what 10 things effect the eligibility of a lung transplant
- Osteoporosis
- Musculoskeletal disease
- Use of corticosteroids (>20mg/day)
- Malnutrition= 130% ideal body weight
- Substance abuse/ addiction
- Smoking within 4mths of activation on the transplant list
- Psychosocial problems – high risk of poor outcome
- Mechanical ventilation
- Colonization of fungi
- Previous thoracotomy, sternotomy, scarring, etc.
what are the 4 types of lung transplants (and each subset)
- Single Lung Transplant= Right or Left
- Double lung transplant= En Bloc or Bilateral sequential
- Heart-lung block
- Ex-Vivo Lung Transplant
7 indications for a single lung transplant
COPD/ Emphysema
Idiopathic Interstitial Pulmonary Fibrosis
Sarcoidosis
Eosinophilic Granuloma
Lymphangiolyomyomatosis
Primary Pulmonary Hypertension
Eisenmengers Syndrome with cardiac repair
for a single lung transplant, which side is easier
Left side is easier
is CPB necessary for single lung transplants
No CPB is necessary – usually
–Depends on patient’s tolerance to unilateral support during cross clamp.
for a single lung transplant, where is the incision
Posterolateral thoracotomy through bed of excised 5th rib.
where is the patient clamped for a single lung transplant and what happens if they don’t tolerate it well
Main PA is encircled and temporarily clamped
- Assess the impact on hemodynamic stability and gas exchange
- If not tolerated, femoral cannulation is used, and patient placed on CPB
what are the steps of a single lung transplant
Usually stay warm Native lung is excised Left Atrium is clamped Pulmonary veins are attached to LA Cuff. PA is anastomosed End to end anastomosis of the donor&recipient bronchus Atrial clamp is removed.
what are 5 indications of Bilateral Sequential Double Lung transplant
Cystic Fibrosis Bronchiectasis Emphysema Primary Pulmonary Hypertension Eisenmenger’s Syndrome with cardiac repair
what the main benefit of a double lung transplant
gives patients a better pulmonary reserve
double lung used to be done ___ where each lung was implanted separately through a pleural-pericardial window while on CPB.
en bloc
- -Utilized Clamshell incision
- -BIG PAIN from a perfusion standpoint
Now, common to do bilateral sequential. describe the process
- Like 2 single lung transplants.
- Ventilate the native lung, while the first goes in. Then ventilate the new lung while the second goes in
Ex Vivo Lung Perfusion: what is it and what are the benefits?
Therapy applied to donor lungs outside the body before transplantation
- Improves organ quality
- Allows lungs that were previously unsuitable for transplantation – safe for transplantation.
- Expands donor pool
how long is the Ex Vivo Lung Perfusion
3-4 hours
how is Ex Vivo Lung Perfusion performed
- Donor lungs placed inside plastic dome
- Attached to ventilator, pump and filters
- Maintained at normal body temperatures
- Treated with a bloodless solution that contains nutrients, proteins, oxygen (Reverse lung injury and Remove excess water)
- Once suitable – transplanted into waiting patient
First human liver transplant was done when and where?
in 1963 by Thomas Starz in Denver, CO.
what year marked the first time a liver transplant patient lived to 1 year post surgery
1967
general guidelines for liver transplants
Any patient with a chronic or acute liver disease who is unable to sustain normal quality of life or patients with serious complications related to the underlying liver pathology should be considered
liver transplant procedure:
- Donor Organ usually arrives prior to incision. Organ is prepped at the back table.
- Incision is made, liver is mobilized.
- Test Clamp is performed.
- -what is done is the patient is stable? what is they are not stable?
If patient remains stable – can do it without V-V bypass. If not, V-V bypass is initiated.
liver transplant procedure:
- Liver is excised and removed.
- New Liver is sewn in
- -what 5 areas are attached
- Suprahepatic IVC
- Infrahepatic IVC
- Portal Vein
- Hepatic Artery
- —Clamps are removed – Bypass is discontinued - Bile Duct
Less than __% of liver transplants use V-V Bypass.
5%
Instead of V-V Bypass for liver transplants, what is the new technique? describe it
Piggy-Back
Use a partial occlusion clamp on the IVC without cross clamping the entire IVC
a liver transplant via V-V bypass was first done when and by whom? what was the patients condition
First used by Marshall, Et al in 1970
Managed a patient with renal cell carcinoma extending into the IVC and RA
in the 1960s – realized that they needed a shunt that could train blood from the lower extremities and portal system. What 2 things did they try
- Utilizing bypass without a pump
- -Unsuccessful – circuit clotted, and created embolism - Tried anticoagulation
- -Increased bleeding too much
when did V-V Bypass came into practice with the use of heparin bonded circuits and a centrifugal pump
1980s
describe V-V bypass: equipment/ flows
- No oxygenator
- Centrifugal pump
- Less flows than on CPB
- Flows from 1-2 liters most common
describe V-V bypass: cannulation sites
- Femoral vein is cannulated and advanced to the bifurcation of the IVC
- 2nd cannula placed in the portal vein to drain the portal system
- Return to axillary vein or internal jugular vein
is heparin used for a liver transplant
nope
why should the flow not drop below 1 LPM with a liver transplant
Need to maintain flow to prevent clot
Preload dependent
why cant fluid be added with a liver transplant
Closed system, so no volume can be added
