Abstract 3336: Early Management and Norepinephrine Withdrawal But Not Hormonal Therapy, Improve Donor Heart Function
Objectives: To assess the role of early management, tri-iodothyronine (T3) and methylprednisolone (MP) therapy in potential heart donors.
Methods: In a prospective randomized double blind trial, 80 potential cardiac donors (mean age 43±13.1), were allocated to receive T3 (0.8μg kg−1 bolus; 0.113μg.kg−1. hr−1 infusion), MP (1000mg bolus), both drugs or placebo following consent and baseline assessment. Strict algorithmic optimization of pre- and after-load was instituted substituting inotropes and norepinephrine (NE) with vasopressin. Trans-thoracic echocardiography (TTE) was undertaken at baseline and pre-retrieval.
Results: Optimization commenced within 2±0.5 hours of consent, and 12±0.2 hours of coning, and this was continued for 6.7±1.5 hours. Randomized drug treatment was delivered for 5.7±1.5 hours. At the time of retrieval right and left ventricular stroke work index had increased from 4.9±3 g-m.m−2.beat−1 to 7.5±4 (p<0.001) and 40.6±14.5 g-m.m−2.beat−1 to 46±17.8 (p=0.007) in the entire cohort. This was associated with an increase in both central venous pressure (8.6±4mmHg to 11.0±3.6 (p<0.001)) and pulmonary capillary wedge pressure (9.4±4.4mmHg to 12.6±4.1 (p<0.001)). At baseline, 48/80 donors were receiving NE (0.2±0.256μg.kg−1.min−1), which was weaned completely in 26 donors and reduced to 0.06±0.12 μg.kg−1.min−1 (p<0.001)) in the remaining 22 donors. This was associated with a rise in cardiac index (3.2±1.12L.min−1.m−2 versus. 3.7±1.19 (p<0.001)). On TTE baseline wall motion score (WMS) was abnormal (>1) in 37 donors, improving with optimisation in 18 from 2.2±0.6 to 1.8±0.68 (p<0.001), and deteriorating despite optimal management in 19(1.8±0.47 vs. 2.04±0.5 p<0.001). Improving WMS was associated with reducing NE (p=0.015), whilst donors in whom inotropic support could not be weaned demonstrated deteriorating WMS. At initial assessment 40/80 hearts were classed as marginal, and of these 14 were transplantable at the end of the optimization period. T3 and MP alone, or in combination, did not affect any of the above parameters.
Conclusion: Early optimisation and reduction of NE significantly improve donor heart function and can increase yield. T3 and MP do not influence this process.