7.3 Heart Transplant and Post-Op Care/Risks Flashcards
Organ Transplants
- Used for End Stage Diseases
Indications
- Ischemic Cardiomyopathy
- Idiopathic Cardiomyopathy
- Valvular Heart Disease
- Congenital Anomalies
Patient Evaluation
General
- Treatment begins during evaluation phase
- The goal is to have the patient in the best physical condition for transplant, this includes adequate nutrition, mobility, and muscle strength.
Age
- BIOLOGIC AGE (how well they function) NOT CHRONOLOGIC AGE (how old they are)
- Anywhere between infant to 70
- Age 55+ is increased risk
ABSENCE OF INFECTION
- No infections before transplants
- Localized liver infections CAN BE AN EXCEPTION
- Inflammatory diseases do not rule out transplants (lupus) but should be dormant (quiescent) during procedure)
Health
- ABO Typing
- Matching
- Transfusion History
- Infectious disease screening
- Liver/Renal Function Tests
- CBC
- Coagulation studies
- GI Evaluation
- Gynecology
- ECG
- Dental Exam for Infection
- Social History
Criteria
- Put on UNOS list based on blood type and listing data
- Size of organ is important
- Patients require heart transplants AND inotropic medications or ventricular assistance are at higher priority
Requirements (any of the below)
- Cardiac Disease
- Not treatable with other interventions
- Less than 25% survival at the end of the year without transplant
- Fatal dysrhythmias
Contraindications for Heart Transplant
- Fixed pulmonary hypertension
PVC - greater than 6-8 Wood Units - Recently unsolved pulmonary infarct (increases risk of infection)
- Poorly controlled diabetes mellitus
- Right heart catheterization or full
Evaluation for Transplant
- Cardiopulmonary Exercise Test (MVO2)
- Pulmonary function tests (diffusion capacity - DLCO)
- Cardiac Rehabilitation consultant
- Multigated Acquisition (MUGA) or Echocardiogram
Donor Selection
- Must be ABO compatible
Tissue Typing
- Histocompatibility testing (tissue typing)
- Identification of donor antigens verse recipient antibodies which predicts graft acceptance
HLA
- Major histocompatibility complex
- Class 1 antigen - Present on surface of all nucleated cells and platelets.
- Class 2 antigen - Found on surface of lymphocytes
- Each person has 6 (A-, B-, DR- Antigens)
- The higher number of matching antigens, the higher likelihood of compatibility.
- 6 Antigen match is the best
PRA
- When patients are receiving a non-living donation a pool of random donors is tested against the recipient.
- The higher the percentage of samples the patient reacts to (Panel Reactive Antibody - PRA percentage) - the higher the risk
Blood Transfusions
- Avoided in patients awaiting heart transplants due to risk of antibody production which results in high PRA or positive cross-match between donor and recipient.
Orthotopic Transplants
- Classic and most common transplant
- Heart is taken out of recipient and replaced with donors
Lower and Shumway Technique
- Gold Standard
- Atrial to Atrial Cuff
Complications
- Mitral/Tricuspid Regurgitation
- Atrial Thrombus Formation
- Tachydysrhythmias
Bicaval Technique
- Preserves anatomy of atrium
- Anastomoses is between inferior and superior vena cava instead of atria
Heterotopic Transplant
- Piggyback Procedure
- Recipient heart is left in place and donor heart is placed next to it in the right chest.
- 2 Hearts are then connected together.
Indications
- Patients with pulmonary hypertension
- Can also be used in an emergency if donor heart is too small for the recipient
Limitations
- Thromboembolism from native heart would need anticoagulation
- Limited chest space
- Survival rates are lower
POST OP CARE
- VS
- Oxygen
- Ventilator settings
- LOC and degree of pain
- Note number of IV and arterial lines
- Note site, type of solution and flowrate
- Note presence of drainage and amount/type
- Presence of catheters, patency, and urinary drainage
- Appropriate amount and character of NG tube drainage
- Most recent hemodynamic and intraoperative laboratory results
POST OP CARE (HEART)
- There maybe 2 P waves on ECG
- Denervation (loss of nerve supply) may cause high HR, sympathetic stimulation may be absent, medications on autonomic nervous system may have abnormal effects
- Potential ventricular failure (treat with medications to decrease right heart afterload)
Denervation
- Medication effects are abnormal
- Atropine does not work
- Use Dobutamine and Epinephrine with Epicardial Pacing instead of Isoproterenol to manage bradydysrhythmias
- Digitalis does not work because it is mediated by the parasympathetic nervous system
- PATIENT DOES NOT FEEL PAIN (ischemia or MI can go unnoticed) - ECG stress tests and coronary angiographs are preformed
Right Sided HF Treatment
- Drugs to decrease right side afterload (dobutamine, milrinone, inhaled nitrous oxide)
- Nitrous oxide is a pulmonary vasodilator
- Administered via lungs so it avoids systemic effects administered IV.
Risk Factors for Right Side HF
- Hypoxia
- Acidosis
- Excessive Blood Transfusions (AVOID)
Immunosuppressive Therapy
- Immunosuppression to prevent rejection
- Goals are to avoid toxicity, unfavorable reactions, and reduce susceptibility to opportunistic infections
Triple Therapy
- Prednisone, Azathioprine, Cyclosporine/Tacrolimus
Quadruple Therapy
- Same as above and antithymocyte antibody or monoclonal antibody (monomurab)
Induction and Maintenance
Induction - Immediately after transplant, high dose of immunosuppression
Maintenance - Lower dose once stable
Complications of Immunosuppression
