Evaluation of Perfusion Modes on Vital Organ Recovery and Thyroid Hormone Homeostasis in Pediatric Patients Undergoing Cardiopulmonary Bypass *Atif Akçevin, *Tijen Alkan-Bozkaya, †Feng Qiu, and †Akif Ündar *Department of Cardiovascular Surgery, Istanbul Bilim University, Istanbul,Turkey; and †Departments of Surgery and Bioengineering, Penn State Hershey Pediatric Cardiovascular Research Center, Penn State Milton S. Hershey Medical Center, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, PA, USA Abstract: The objectives of this study were: (i) to evalu- ate the effects of perfusion modes (pulsatile vs. nonpulsa- tile) on vital organs recovery and (ii) to investigate the influences of two different perfusion modes on the homeostasis of thyroid hormones in pediatric patients undergoing cardiopulmonary bypass (CPB) procedures. Two hundred and eighty-nine consecutive pediatric patients undergoing open heart surgery for repair of con- genital heart disease were prospectively entered into the study and were randomly assigned to two groups: the pul- satile perfusion group (Group P, n = 208) and the nonpul- satile perfusion group (Group NP, n = 81). All patients received identical surgical, perfusional, and postoperative care. Study parameters included total drainage, mean urine output in the intensive care unit (ICU), intubation time, duration of ICU and hospital stay, the need for ino- tropic support, pre- and postoperative enzyme levels (ALT [alanine aminotransaminase] and AST [aspartate aminotransaminase]), c-reactive protein, lactate, albumin, blood count (leukocytes, hematocrit, platelets), creatinine levels, and thyroid hormones (thyroid stimulating hormone [TSH], FT3 [free triiodothyronine], FT4 [free thyroxine]). All patients survived the perioperative and postoperative periods. There were no statistically signifi- cant differences in either preoperative or operative parameters between the two groups. Group P, compared to Group NP, required significantly less inotropic support, had a shorter intubation period, higher urine output in ICU, and shorter duration of ICU and hospital stay. Lower lactate levels and higher albumin levels were observed in Group P and there were no significant differ- ences in creatinine, enzyme levels, blood counts, or drain- age amounts between two groups. TSH, Total T 3, Total T4, and FT3, FT4 levels were markedly reduced versus their preoperative values in both groups. FT3 and FT4 levels were reduced significantly further in the nonpulsatile group both during CPB and at 72 h postoperation. The results of this study confirm our opinion that pulsatile per- fusion leads to better vital organ recovery and clinical outcomes in the early postoperative period as compared to nonpulsatile perfusion in pediatric patients undergoing CPB cardiac surgery. The plasma concentrations of thyroid hormones are dramatically reduced during and after CPB, but pulsatile perfusion seems to have a protec- tive effect of thyroid hormone homeostasis compared to nonpulsatile perfusion. Key Words: Pulsatile perfusion —Vital organ recovery—Cardiopulmonary bypass—Con- genital heart defect—Pediatric—Thyroid hormone levels. The cardiopulmonary bypass (CPB) procedure has been used in pediatric patients with congenital heart disease all over the world. The progress in congenital heart surgery and CPB technology has significantly reduced the mortality of CPB procedures; however, there is still a large need for improvement in CPB procedures, as many children who survive open heart surgery encounter a series of problems induced by CPB, including neurological injury and vital organ dysfunction (1–3). The etiology of CPB-related morbidity is believed to be multifactorial, including the prolonged duration of CPB, the application of deep hypothermic circula- tory arrest, the interaction between the blood and the artificial surface of the CPB circuit, as well as the doi:10.1111/j.1525-1594.2010.01159.x Received August 2010; revised September 2010. Address correspondence and reprint requests to Professor Akif Ündar, Penn State Hershey College of Medicine, Department of Pediatrics—H085, 500 University Drive, P.O. Box 850; Hershey, PA 17033-0850, USA. E-mail: aundar@psu.edu Presented in part at the 6th International Conference on Pedi- atric Mechanical Circulatory Support Systems and Pediatric Car- diopulmonary Perfusion held May 6–8, 2010 in Boston, MA, USA. Artificial Organs 34(11):879–884, Wiley Periodicals, Inc. © 2010, Copyright the Authors Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc. 879