Heart Transplant Patient

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Heart Transplant Patient
9/11/10
OHOA
JFICIM and FANZCA Examinations Book – page 183-185
SP Notes
PY Mindmaps
CRITERIA FOR CARDIAC TRANSPLANT RECIPIENT
Clinical
-
NYHA class III/IV heart failure refractory to maximal medical therapy
severe limiting angina not suitable for revascularization
recurrent symptomatic ventricular arrhythmia refractory to treatment
estimated life expectancy of < 12 months
Physiological
- peak O2 consumption less than 10mL/kg/min after reaching anaerobic threshold
EXCLUSION CRITERIA
-
age > 65 yrs
pulmonary hypertension (not reversible with nitrates or inhaled NO)
IDDM with end-organ damage
severe psychiatric disturbance or intellectual retardation
current alcohol or drug abuse
morbid obesity
malignancy
severe hepatic or renal disease
immunuodeficiency disease
active systemic infection
HISTORY
- cause of cardiac failure and symptoms patients had
- functional limitations
- surgery and perioperative course
- complications: rejection, infection, coronary vascular disease, malignancy, hyperlipidaemia
and HT
- currently exercise tolerance
- previous anaesthetic history after transplant
- symptoms of rejection and cardiac performance (symptoms of rejection: unexplained weight
gain, or fever, recent cardiac biopsy result – Bilingham grade)
- symptoms of heart failure seen or arrhythmia
- donor heart IHD – don’t get pain because heart denervated
- ability to work
Medications
Jeremy Fernando (2011)
- standard + immunosuppressants
3 classes of drugs used:
1. Immunophilin binding drugs (cyclosporin, tacrolimus) – prevent cytokine-mediated T
cell activation and proliferation
2. Nucleic acid synthesis inhibitors (azathioprine) – block lymphocyte proliferation
3. Steroids (prednisone) – block production of inflammatory cytokines, lyse T lymphocytes
and alter the function of remaining lymphocytes.
- anaemia, thrombocytopaenia and leukopaenia -> may require treatment
- all can predispose to; infection, malignancy (SCC of skin, lymphoma), OA, CRF
- cyclosporine – associated with HT, renal dysfunction, prolonged effect of NDNMBD, calcium
antagonists are used to increase cyclosporine levels
- tacrolimus – renal dysfunction
- recent biopsy and angiography results
EXAMINATION
- weight
- BP
- CVS: high HR, no variation, pacemaker, sternotomy, scars over RIJ from biopsies, HS and
lungs
INVESTIGATIONS
-
ECG: look for second (native p wave), RBBB
angio:
ECHO: intramural thrombi and ventricular function
FBC
U+E
drug levels
CXR
MANAGEMENT
Bridge to Transplant Therapies
-
ACE-I
beta-blockers
inotropes
intra-aortic balloon pump
implantable defibrillators
cardiac resynchronisation
advanced pacing devices
surgical interventions (CABG, anterior ventricular wall remodelling, mitral reconstruction)
VAD
totally implanted artificial heart
Jeremy Fernando (2011)
Donor coronary artery disease
- immune mediated
- very common
- will not get angina as heart denervated
-> aggressive maintenance of coronary artery perfusion and oxygenation
Rejection
- look for: weight gain, fluid retention, pyrexia, decreased cardiac function on ECHO
- don’t cannulate RIJ as this is were cardiac biopsies are taken from
Immunosuppression
- must be continued perioperatively and in ICU
- look out for drug interactions
- drug side effects: chronic renal impairment, HT, DM, bone marrow suppression,
hepatotoxicity
- prone to infections (including atypical and opportunistic): strict asepsis, remove all
unnecessary lines/drains early
- if infections suspected: get cultures and start antimicrobials early, involve ID early, increase
steroids
- monitor for malignancy
Respiratory
- may have phrenic or recurrent laryngeal nerve palsy -> poor cough
- if has had lung transplant be aware of tracheal anastomosis on intubation (appropriate tube
size and check pressure)
Other common diseases
-
PVD
DM
sarcoid
amyloid
epilepsy
HT
Altered Physiology
- 10% have pacemaker
- 10% have RBBB
- no autonomic innervation: HR around 90/min, loss of vagal tone, no heart rate changes
with stimulation -> wide swings in BP c/o reliant on maintenance of pre and afterload
- marked hypotension with central neuraxial anaesthetic techniques
- contractility preserved unless rejection taking place
Altered Pharmacology
Jeremy Fernando (2011)
- use direct acting agents: adrenaline, noradrenaline, isoprenaline and beta-blockers,
phenylephrine
- atropine: no effect on HR
- adenosine: more sensitive -> start with 1mg
- digoxin: minimal delay in AV conduction -> not a good anti-arryhthmic here
- adrenaline and noradrenaline: increased contractility and chronotropy
- beta-blockers: increased antagonistic effect
- pancuronium: no bradycardia
- sux: no bradycardia
- neostigmine: no bradycardia
- isoprenaline: normal effects
- GTN: no reflex tachycardia
- suxamethonium, neostigmine: no bradycardia
Jeremy Fernando (2011)
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