Pediatric Cardiopulmonary Bypass Adaptations for Long-Term Survival of Baboons Undergoing Pulmonary Artery Replacement

• Published in: The Journal of extra-corporeal technology Vol. 42; no. 3; pp. 223 - 231
• Main Authors: WHITTAKER, Carrie, GRIST, Gary, LOFLAND, Gary K, HOPKINS, Richard A, BERT, Arthur, BRASKY, Kathleen, NEIGHBORS, Stacy, MCFALL, Christopher, HILBERT, Stephen L, DRAKE, William B, CROMWELL, Michael, MUELLER, Barbara
• Format: Journal Article
• Language: English
• Published: Richmond, VA American Society of Extra-Corporeal Technology 01-09-2010; American Society of ExtraCorporeal Technology
• Subjects: Abstract; Anesthesia; Anesthesia depending on type of surgery; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; Biological and medical sciences; Biotechnology; Blood Vessel Prosthesis Implantation; Cardiopulmonary Bypass - methods; Cardiopulmonary Bypass - mortality; Fundamental and applied biological sciences. Psychology; Health. Pharmaceutical industry; Heart Valve Prosthesis Implantation; Industrial applications and implications. Economical aspects; Male; Medical sciences; Miscellaneous; Models, Animal; Papio; Pulmonary Artery - surgery; Pulmonary Valve - surgery; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Survival Rate; Tissue Engineering; Pediatrics; allografts; Prognosis; xenografts; Monkey; Homograft; Transplantation; Heterograft; Heterotransplantation; Heart valve; right ventricular outflow tract; Pulmonary vessel; homografts; Surgery; Blood vessel; Primates; Graft; subhuman primates; tissue engineered heart valve; Child; Adaptation; Human; Tissue engineering; Long term; Survival; Pulmonary valve; Pulmonary artery; Baboon; Cardiopulmonary bypass; Vertebrata; Mammalia; Treatment; Animal; Circulatory system
• ISSN: 0022-1058; 2969-8960
• DOI: 10.1051/ject/201042223

Cardiopulmonary bypass (CPB) protocols of the baboon (Papio cynocephalus anubis) are limited to obtaining experimental data without concern for long-term survival. In the evaluation of pulmonary artery tissue engineered heart valves (TEHVs), pediatric CPB methods are adapted to accommodate the animals' unique physiology enabling survival up to 6 months until elective sacrifice. Aortic access was by a 14F arterial cannula and atrial access by a single 24F venous cannula.The CPB circuit includes a 3.3 L/min flow rated oxygenator, 1/4" x %" arterial-venous loop, 3/8" raceway, and bubble trap. The prime contains 700 mL Plasma-Lyte, 700 units heparin, 5 mL of 50% dextrose, and 20 mg amiodarone. Heparinization (200 u/kg) targets an activated clotting time of 350 seconds. Normothermic CPB was initiated at a 2.5 L/m2/min cardiac index with a mean arterial pressure of 55-80 mmHg. Weaning was monitored with transesophageal echocardiogram. Post-CPB circuit blood was re-infused. Chest tubes were removed with cessation of bleeding. Extubation was performed upon spontaneous breathing. The animals were conscious and upright 3 hours post-CPB. Bioprosthetic valves or TEHVs were implanted as pulmonary replacements in 20 baboons: weight = 27.5 +/- 5.6 kg, height = 73 +/- 7 cm, body surface area = 0.77 m2 +/- 0.08, mean blood flow = 1.973 +/- .254 L/min, core temperature = 37.1 +/- .1 degree C, and CPB time = 60 +/- 40 minutes. No acidosis accompanied CPB. Sixteen animals survived, four expired. Three died of right ventricular failure and one of an anaphylactoid reaction. Surviving animals had normally functioning replacement valves and ventricles. Baboon CPB requires modifications to include high systemic blood pressure for adequate perfusion into small coronary arteries, careful CPB weaning to prevent ventricular distention, and drug and fluid interventions to abate variable venous return related to a muscularized spleno-splanchnic venous capacity.