Tijen Alkan-Bozkaya

Evaluation of Perfusion Modes on Vital Organ Recovery and Thyroid Hormone Homeostasis in Pediatric Patients Undergoing Cardiopulmonary Bypass

The objectives of this study were: (i) to evaluate the effects of perfusion modes (pulsatile vs. nonpulsatile) 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 congenital heart disease were prospectively entered into the study and were randomly assigned to two groups: the pulsatile perfusion group (Group P, n = 208) and the nonpulsatile 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 inotropic 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], FT(3) [free triiodothyronine], FT(4) [free thyroxine]). All patients survived the perioperative and postoperative periods. There were no statistically significant 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 differences in creatinine, enzyme levels, blood counts, or drainage amounts between two groups. TSH, Total T(3) , Total T(4) , and FT(3) , FT(4) levels were markedly reduced versus their preoperative values in both groups. FT(3) and FT(4) 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 perfusion 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 protective effect of thyroid hormone homeostasis compared to nonpulsatile perfusion.

Impact of Pulsatile Perfusion on Clinical Outcomes of Neonates and Infants With Complex Pathologies Undergoing Cardiopulmonary Bypass Procedures

The aim of this clinical trial was to evaluate the pulsatile perfusion mode in pediatric patients who had complex cardiac pathologies according to Jenkins stratifications (category 4) undergoing cardiopulmonary bypass procedures (CPB). Patients with transposition of great arteries (TGA) and ventricular septal defect (VSD) were included in this clinical study. Eighty-nine consecutive pediatric patients undergoing open heart surgery for repair of TGA-VSD were prospectively entered into the study and were randomly assigned to either the pulsatile perfusion group (Group P, n = 58) or the nonpulsatile perfusion group (Group NP, n = 31). There were no differences between groups in terms of demographical and intraoperative parameters. The pulsatile group needed significantly less inotropic support (P < 0.05) and had lower lactate levels (P < 0.001), higher urine output (P < 0.01), and higher albumin levels (P < 0.05). In addition, the pulsatile group had less ICU (P < 0.01) and hospital stays (P < 0.001). We conclude that the use of pulsatile flow is a better option and should be considered for repair of the complex congenital heart defects.

Istanbul Symposiums on Pediatric Extracorporeal Life Support Systems

The most recent and rapid changes in pediatric extracorporeal life support systems (ECLS) and cardiopulmonary bypass (CPB) procedures are remarkable in terms of not only the development of significantly improved circuit components but also new techniques that reduce morbidity and mortality in pediatric cardiac patients,particularly neonates and infants (1–14). The objective of this editorial is to present the outcomes of the two most recent ECLS symposiums held at the Swiss Hotel and the Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital (IMAEH) in Istanbul, Turkey on June 26, 2011 and July 23, 2011, respectively. The main goal of these two symposiums was to share the most recent advances in a custom-made ECLS system that was developed at the Pediatric Cardiovascular Research Center at Penn State Hershey College of Medicine and Penn State Hershey Children’s Hospital, Hershey, PA, USA with invited clinicians around the Republic of Turkey. The custom ECLS system has many advantages including significantly less priming volume (<190 mL), less priming and setup time (<10 min), continuous monitoring no longer being required, and a reasonable disposal cost (<

Translational Research in Pediatric Extracorporeal Life Support Systems and Cardiopulmonary Bypass Procedures: 2011 Update

2500) compared with conventional systems (15). Scientific committee members were composed of both local and international faculty members with multidisciplinary backgrounds and included pediatric heart surgeons, cardiologists, perfusionists, a pediatric critical care nurse educator, and a scientist. The format of both symposiums included not only invited lectures but also hands-on wet lab training sessions.

Correlation between cerebral-renal near-infrared spectroscopy and ipsilateral renal perfusion parameters as clinical outcome predictors after open heart surgery in neonates and infants.

Over the past 6 years at Penn State Hershey, we have established the pediatric cardiovascular research center with a multidisciplinary research team with the goal to improve the outcomes for children undergoing cardiac surgery with cardiopulmonary bypass (CPB) and extracorporeal life support (ECLS). Due to the variety of commercially available pediatric CPB and ECLS devices, both in vitro and in vivo translational research have been conducted to achieve the optimal choice for our patients. By now, every component being used in our clinical settings in Penn State Hershey has been selected based on the results of our translational research. The objective of this review is to summarize our translational research in Penn State Hershey Pediatric Cardiovascular Research Center and to share the latest results with all the interested centers.

Cardiac Surgery of Premature and Low Birthweight Newborns: Is a Change of Fate Possible?

The objective of this clinical study is to determine whether correlation exists among cerebral and renal near-infrared spectroscopy (NIRS) measurements, renal Doppler ultrasonography parameters (resistive index, peak systolic velocity), and early postoperative clinical outcomes following cardiac surgery in neonates and infants. Thirty-seven patients undergoing surgery for congenital heart defects with an age of less than 3 months, all of whom were in the high-risk group according to Aristotle Basic Complexity risk stratification score, were enrolled in our study. Cerebral, renal NIRS values and renal Doppler ultrasonography measurements were recorded for each patient at the 4th postoperative hour. The renal resistive indices were calculated for each case, and the patients were divided into two groups according to renal resistive index (RI) values. Group I included the patients with a RI of greater than 0.8 (n = 25) and Group II included the patients with a RI of less than 0.8 (n = 12). The postoperative outcome parameters were compared in between two groups. Group I (RI >0.8) had lower postoperative mean urine output than Group II (RI <0.8) (P = 0.041). The lactate levels were significantly higher in Group I (P = 0.049), as well. The postoperative intensive care unit and hospital stay of Group I was significantly higher than Group II (P = 0.048). Both cerebral and renal NIRS values and the assessment of renal RI as well as peak systolic values can be used in order to predict the early clinical outcome in cardiac surgery patients in early infantile and neonatal period.

Outcomes of the Eighth International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion

Low birthweight (LBW) continues to be a high-risk factor in surgery for congenital heart disease. This risk is particularly very high in very low birthweight infants under 1500g and extremely LBW infants under 1000g. From January 2005 to December 2008, 33 consecutive LBW neonates underwent cardiac surgery in our clinic in keeping with the criteria for choice of surgery. Their weight range was between 800 and 1900g. Nine of them were under 1000g. Cardiopulmonary bypass (CPB) was used in 17 patients (39.5%) and pulsatile perfusion mode was applied to patients in the CPB group. The same surgical team operated to achieve palliation (8 patients, 24.2%) or full repair (25 patients, 75.8%). Median gestational age was 36 weeks with 12 (36.4%) premature babies (≤37 weeks). Median age at operation was 5 days. Pathologies were single ventricle (n=3), pulmonary atresia-ventricular septal defect (n=3), aortic coarctation (n=10), aorticopulmonary window and interrupted aortic arch combination (n=6), patent arterial duct (n=11), critical aortic stenosis (n=8), and tetralogy of Fallot with pulmonary atresia (n=2). One infant had VATER syndrome. Selective cerebral perfusion technique was used in complex arch pathologies for cerebral protection. Median follow-up was 14 months. There were four early postoperative deaths. None of the cases showed a need for early reoperation. The acceptable early- and midterm mortality rates in this group suggest that these operations can be successfully performed. There is a need for further multicenter studies to evaluate these high-risk groups.

Istanbul Symposium on Neonatal and Pediatric Cardiopulmonary Bypass Procedures

The Eighth International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion was held at the Galatasaray University, Istanbul, Turkey, June 13–16, 2012 (Fig. 1).Atif Akcevin, MD, was the local chair of the conference. The scientific co-chairs of the eighth event were Atif Akcevin, Tijen Alkan-Bozkaya, Ihsan Bakir, Hakan Ceyran, Yves Durandy, Huriyet Ersayin-Kantas, Colleen E. Gruenwald, David Palanzo, Linda Pauliks, Kerem Pekkan, Chitra Ravishankar, Eugen Sandica, Kyung Sun, Riza Turkoz, Akif Undar, Bonnie Weaver, and John L. Myers. As we stated in the past seven editorials, the overall objective of the meeting was and still is to bring together internationally known clinicians, bioengineers, and basic scientists involved in research on pediatric mechanical circulatory support systems and pediatric cardiopulmonary bypass procedures. Primarily, we focus to explicitly describe the problems with current pediatric mechanical circulatory support systems, methods, and techniques during acute and chronic support and to suggest solutions and future directions for research (1–3). Over 200 participants from 20 countries participated at the eighth annual event. One hundred one formal presentations including a keynote lecture, 40 invited lectures, 29 oral, and 32 poster presentations began on Thursday morning June 14, 2012 and continued through Saturday evening June 16, 2012. To date, over 800 presentations (320 invited lectures, 220 slide, and 260 poster presentations) and 400 peer-reviewed articles were published based on this unique event (http://pennstatehershey.org/web/ pedscpb/home). It was a great honor to have William S. Pierce, MD, from Penn State Hershey College of Medicine, as the keynote lecturer. His lecture entitled “A 40-Year Odyssey in Mechanical Circulatory Support” was a great historic lecture and it was a privilege to listen to his talk (Figs. 2 and 3a,b). In addition, platform presentations took place in 2-h blocks during the morning and afternoon sessions on Thursday, Friday, and Saturday. Plenary sessions were held throughout the conference focusing on key topics including “Managing the Single Ventricle Patient from Fetus to Definite Treatment” (led by co-chairs David Anderson, MD, and John L. Myers, MD), “Pediatric MCS—Devices & Outcomes” (led by co-chairs William S. Pierce, MD, and Kyung Sun, MD, PhD, MBA), “Bioengineering Approaches in Pediatric Cardiovascular Medicine” (led by Akif Undar, PhD, and Jeffrey D. Zahn, PhD), “Extracorporeal Life Support” (led by Chitra Ravishankar, MD, and Bonnie Weaver, RN, CCRN), “Multi-Disciplinary Team Approach to Solve the Complex Problems in Neonatal and Pediatric Cardiac Surgery” (led by Ihsan Bakir, MD [Turkey], and Tayyar Sarioglu, MD), “Cardiopulmonary Perfusion” (led by Colleen E. Gruenwald, PhD, and David Palanzo, CCP), “Myocardial Protection during CPB” doi:10.1111/j.1525-1594.2012.01562.x FIG. 1. Halil Tűrkoglu, William S. Pierce, PeggyJayne Pierce, Akif Undar, Ihsan Bakir, and John L. Myers. bs_bs_banner

Penn state hershey - Center for pediatric cardiovascular research: Guest editorial

Last summer, after organizing two Istanbul symposiums on pediatric extracorporeal life support systems, the third one was held on December 17, 2011 at the American Hospital in Istanbul, Turkey (1). The main topic of the third symposium was “minimizing adverse effects of cardiopulmonary bypass procedures in neonates and pediatric cardiac patients.”The objective of this editorial is to present the outcomes of the third symposium and suggest more topics for future symposiums in 2012. The third symposium is dedicated to honor Prof. Dr. Aydın Aytaç for his lifelong contributions as a pioneering surgeon and educator of the development of pediatric cardiac surgery in Turkey (Fig. 1) (2–6).

Impact of Pulsatile Flow on Vital Organ Recovery During Cardiopulmonary Bypass in Neonates and Infants.

With the creation of the Penn State Hershey - Center for Pediatric Cardiovascular Research, we strive to become one of the leading centers for the innovation and development of novel devices and treatments for congenital heart surgery. We also seek to educate more bioengineers, medical students, residents, post-doctoral fellows, and junior faculty members in pediatric cardiovascular research. Finally, we seek to continue the growth of our conference (The International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion - http://www.hmc.psu.edu/childrens/pedscpb/), in order to provide a scientific venue for the pioneering research being performed in pediatric mechanical circulatory support and cardiopulmonary perfusion. Our website (http://www.pennstatehershey.org/web/childrensheartgroup/research/overview) includes an overview of all of our current projects (clinical, basic science, and bioengineering), publications, presentations, as well as national and international collaborators affiliated with our center. Investigators interested in collaborating with us on current or new projects should send an e-mail to ude.usp@radnua. Special thanks go to all those who support our collaborative efforts, both intellectually and financially each year. This includes significant financial support from the Penn State Hershey Children’s Hospital and Penn State Hershey College of Medicine, the National Heart Lung and Blood Institute, and the National Institute of Health Office of Rare Diseases. Furthermore, we are most grateful to our dedicated students, sponsors, faculty, and national and international collaborators which make the formation of such an establishment possible.