Post-operative management in CSICU

• Milrinone infusion at a dose of 0.5 mcg/kg/min.
• Isoproterenol infusion for the first 72 hours at starting dose of 0.05 mcg/kg/min can be used in selective cases with low HR and not possible atrial pacing.
• Nitric oxide 20 ppm started in the operating room prior to discontinuation of cardiopulmonary bypass for patients with known or suspected pulmonary hypertension.
• Adequate sedation during the first 24 hours with attention to bleeding, comfort, safety, and adequate cardiopulmonary support.
• Adequate ventilator support with the arterial pO2 > 80 mmHg and the arterial pCO2 < 35 mmHg with goal of arterial pH > 7.40 in the early post-operative period.
• Early identification of right-sided failure and low cardiac output post-transplant secondary to pulmonary hypertension or other issues with surgery and/or graft function. The heart transplant recipient should be considered early for ECMO to allow rest and recovery during the vulnerable peri-operative period. The transplant surgeon and cardiologist should be notified immediately of concerns for graft dysfunction.
• Maintenance immunosuppression (see Table below corresponding to KFSH&RC protocol)
• Treatment of infection and phrophylaxis anti CMV (duration depending status donor-recipient), fungus and Pneumocystis.
• First Endomyocardial Biopsy should be done at 10 days – 2 weeks after transplant (except in children < 1 year of age)

Post-operative assessment in CSICU

• Clinical – vital signs; fever, tachycardia, hypotension or shock– features of hyperacute rejection
• Investigations: Crossmatch results normally at 24 hr. after transplant (if positive risk of humoral rejection), ECHO in OR (TEE) and first days should be done to check biventricular function and data of rejection, Endomyocardial Biopsy at 10 days to check data of rejection (mononuclear infiltrates, fibrinoid necrosis, interstitial hemorrhage. etc), markers of infection and cultures to rule out infection and CMV PCR status each week.

Denervated heart post-transplant

During the surgey of heart transplant, the cardiac plexus is interrupted, and the heart is partially denervated. First days the heart rate and electrical activity of the new heart are purely dependent on the intrinsic electrical system of the heart, not on the neurologic input from the recipient. The resting heart rate is usually higher due to the lack of vagal stimulation which is present at baseline in normal physiology. A higher heart rate is important to augment cardiac output (Cardiac output= Heart rate x Stroke volume), because the donor organ has diastolic dysfunction initially which adversely effects the stroke volume. Isoproterenol, or pacing, can be used to support heart rate. Although cardiac denervation occurs immediately after HTx, cardiac reinnervation is a variable phenomenon and could normalize after days or weeks post-transplant.

  INDUCTION AND IMMUNOSUPPRESSION FIRST POSTOPERATIVE DAYS:

Thymoglobulin® is recommended for heart transplant patients based on the best available evidence: Zuckermann AO, et al. Improved long-term results with thymoglobulin induction therapy after cardiac transplantation: a comparison of two different rabbit-antithymocyte globulines. Transplantation. 2000 May 15;69(9):1890-8.