What is the assessment protocol for a brain-dead adult donor heart before retrieval?

Heart Donor Assessment Protocol Before Retrieval

The assessment protocol for brain-dead adult donor hearts should follow a structured approach beginning with conventional hemodynamic optimization, followed by echocardiographic evaluation, and aggressive hormonal resuscitation for hearts with ejection fraction <45% before declining the organ 1.

Initial Conventional Management (Before Echocardiogram)

Before any cardiac assessment, optimize the donor's physiologic status:

Hemodynamic Targets

• Volume status: Central venous pressure 6-10 mmHg
• Mean arterial pressure: ≥60 mmHg
• Inotrope management: Rapidly taper norepinephrine and epinephrine in favor of dopamine or dobutamine
  • Target dopamine <10 µg/kg/min OR dobutamine <10 µg/kg/min

Metabolic Corrections

• pH: 7.40-7.45
• PO₂: >80 mmHg with O₂ saturation >95%
• PCO₂: 30-35 mmHg
• Hematocrit: 30% (hemoglobin 10 g/dL)

Echocardiographic Assessment

After initial optimization, obtain transthoracic echocardiography to:

1. Rule out structural abnormalities:

   • Significant left ventricular hypertrophy
   • Valvular dysfunction
   • Congenital lesions

2. Assess left ventricular ejection fraction (LVEF):

   • If LVEF ≥45%: Proceed with recovery (consider additional optimization before retrieval) with final evaluation in the operating room 1
   • If LVEF <45%: Do NOT decline the heart immediately—proceed to aggressive management protocol

Critical Caveat: Don't Decline Based on Single Echo

A single echocardiographic assessment may be inaccurate and fails to predict long-term ventricular contractile function—declining a donor heart based solely on initial ejection fraction is not justified 1. The Papworth program demonstrated that 92% of organs failing initial criteria can be functionally resuscitated, expanding their donor pool by 30% 1.

Aggressive Management for LVEF <45%

Pulmonary Artery Catheter Placement

Insert PA catheter for comprehensive hemodynamic monitoring and guided management 1. This approach has proven superior to echocardiography alone for assessing and managing ventricular dysfunction 1.

Hormonal Resuscitation Protocol

Administer the following simultaneously:

1. Triiodothyronine (T₃):

   • 4 µg bolus
   • Then continuous infusion at 3 µg/h

2. Arginine vasopressin:

   • 1 unit bolus
   • Then continuous infusion at 0.5-4 U/h
   • Titrate to systemic vascular resistance 800-1200 dyne·s⁻¹·cm⁻⁵

3. Methylprednisolone:

   • 15 mg/kg bolus

Reassessment Strategy

Research supports a "wait, treat, and see" approach 2. After hormonal treatment, serial echocardiographic monitoring can demonstrate recovery of left ventricular function, with studies showing normalization of hemodynamics and improvement in ejection fraction from 48±15% to 59±3% 2. Consider allowing up to 48 hours for optimization when poor function is the sole reason for declining a heart 3, as the probability of successful heart utilization increases with longer intervals from brain death to assessment, plateauing around 48 hours.

Final Assessment

Perform final evaluation in the operating room with direct visualization and consideration of coronary angiography for eligible donors, particularly those with risk factors 2. The goals are to optimize cardiac output without high-dose β-agonists or inotropes that deplete myocardial high-energy phosphates 1.

Key Pitfall to Avoid

The most common error is prematurely declining hearts based on initial dysfunction without attempting aggressive hemodynamic and hormonal resuscitation. This approach has been shown to safely expand the donor pool by approximately 30% without compromising recipient outcomes 1, 4, 2.