3 Transplants Perfusionists are involved with
Heart, Lung, Liver (any of these can also be performed with a kidney transplant)
-kidney transplants most common, then liver, then lung, then heart
Heart Transplant Patient Selection
- must be in end stage CHF and tried pacers, surgery, meds, LVEF <35%, shock, MI, and must benefit from transplant
- Contraindications (won’t do transplant if)= old age, irreversible pulm HTN (PA systolic above 50-60 mmHg= not good! give iNO to prevent pulm HTN), infections- must be fever free for 72 hours, cancer (WILL do if non-melanoma skin, prostate, or purely heart cancer)
- Not Absolute Contraindications= Obesity (>30 kg/m2), Diabetes, pulm fibrosis, emphysema, hepatic, cerebral disease, Psychosocial
Heart Organ Matching
- ABO compatibility, within 20% of same body weight, HLA Cross match (antibodies), medical urgency, UNOS registry, distance
- Status
- -IA= critical patients (on support, super sick, hospitalized)
- -IB= sick but can go home (VAD >30 days, continuous IV inotropes
- -2= everyone else “relatively stable”
Heart Transplant Technique
- donor CPG arrested and put in preservations
- cut above aortic/pulm valves, leaving PVs and SA node
- 2 techniques= minatorial or bi-atrial (leaving donor atria in tact and cutting at SVC, IVC, and PV)= less distortion of valves, improved function, less AI, less heart block
- Sew from back to front!
- ischemic time 3-4 hours!
- Post Op= patient will be on immunosuppressants and need to be paced for first couple days
- Phys= denervated! = faster resting HR (no vagus tone), no angina- silent MI cuz can’t feel
Perfusion Perspective
- patient in room when harvest team at donor site
- “heart out”- start ischemic time and start patient incision
- go on CPB once heart in room= 32 degrees and XC immediately (no CPG)
- remove heart, trim new heart, replace, rewarm
- hot shot with glutamate aspartate solution when sutures complete
- XC off, place wires, fill heart and wean
Lung Transplant
- Indications= irreversible, progressing end stage pulm disease (oxygen dependent, can’t exercise)
- Evaluation- history, respiratory exam, psychosocial
- Contraindications- osteoporosis, >20 mg/day corticosteroids, malnutrition (must be 75-135% of ideal weight), smoking 4 months before on list, mechanical ventilations, fungi
Types of Lung Transplants
1) single- Left is easier (IVC, SVC on right side), no CPB if other lung can support (fem if needed), posterolateral thoracotomy at 5th rib
—causes= COPD, pulm fibrosis, HTN, Eisenmengers Syndrome!!!!
2) Bilateral Sequential- vent one then switch, no CPB
—causes= cystic fibrosis, bronchiectasis, HTN, Eisenmengers
(en bloc= was used where each lung was trnalspated through pleural-pericardial window while on CPB! 16 hours and don’t hemoconcentrate)
3) Ex Vivo= helps heal bad donor hearts- increasing pool
- 3-4 hours with CPB
-treated with O2, protein, nutrients,
-buffer with extracellular solution, albumin, dextrin 40= protects endothelium
Liver Transplants
- brain damage, ascites, GI bleeding, fatigue, tumor
- can they sustain the operation
- MELD (model for end-stage liver disease)= score tells how urgent
- Criteria for match= blood type, size, distance (12-15 hr)-but MELD trumps distance
Liver Transplant Procedure
- test clamp IVC to see if collaterals have formed = NO CPB (can also piggyback technique with partial clamp)
- if need CPB= veno-veno! (fem and portal vein and return to axillary vein)= NO oxygenator, heparin, or reservoir
- flow 1-2 L/min
- Sew biggest to little
- cold liver can cause heart to fib
- monitor ECG, temp, HR, BP, O2, PA, CO
BTR, BTT, DT
Bridge to recovery
Bridge to tranplant- on waiting list and has worsening hemodynamics
Destination Therapy- can’t transplant, EGF < 25%, class 4 symptoms
VADs Contraindications
surgical risk, stroke, co-estisitng terminal conditions, brain issues, infection, HITT, prig, social support, Pulm HTN/dysfunction
3 Types of VAD pumps
1st- positive displacement/pneumatic= change vol in chambers, air pressure and electricity, large prime volume, unaffected by after load and preload is passive filling
2nd- rotary 3rd- centrifugal = rotating impeller, electricity, small prime, decrease flow with high SVR, and increase flow with high VR
—-all of them have thrombosis with decrease flow and high hemolysis with increase flow
First Generation VADs
-positive displacement, pulsatile flow, one way valves
Thoratec PVAD/IVAD
PVAD= paracorporeal
IVAD= implantable
-can support right, left or both
-Preop risks for RHF- low pressure with high CVP
–low CI with high RAP does’ mean RHF
-BiVAD indicators= high pre-op bilirubin and creatinine
-implanted in anterior abdominal wall
-Implant- CPB, warm, no CPG/XC, LV vent, keep HCT>30
–start with heparin, then move to aspirin and warfarin
INR 2.5-3.5
Heartmate VXE
powered pneumatically or electrically
- tissue valve inside
- cannulate LV apex and aorta
- psuedointima! = textured servos which promotes body to lay down endothelial cells and doesn’t recognize as foreign material = decrease thrombus BUT increase immune activity (antibodies)
- CPB- no CPG or cooling
- must have PFO and AI MS fixed
- goes through diaphragm, and placed in pertinoeal
- only aspirin (good)
- pump malfunctions!!
- 65% survive to transplant (85% if make it past first month)
