550231 research-article2014
PRF0010.1177/0267659114550231PerfusionÜndar et al.
Letter to the Editor
Is it safe to conduct CPB procedures without arterial filters in neonatal and pediatric patients?
Perfusion 2015, Vol. 30(2) 172–173 © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0267659114550231 prf.sagepub.com
A Ündar,1–4 S Wang,1 D Palanzo4 and LD Baer4
Sir, We have read the article entitled “Clinical experience with Affinity PixieTM oxygenation system in paediatric and infant patients” by Issitt and co-workers with great interest.1 The authors stated that “The PixieTM oxygenator proved effective at flows up to 2.5 L/min, with airhandling capabilities comparable with other oxygenators” and “.., therefore, that further testing in a randomised controlled fashion between the PixieTM and competitor oxygenators should be undertaken in a clinical, in vivo setting to establish relative functionality.” It is our opinion that, to select the best possible circuit components for the CPB procedure, in vitro evaluation should be done prior to any in vivo studies, in particular, prior to suggesting randomized clinical trials.2 Although in vitro evaluations cannot replicate the clinical scenarios, invaluable scientific data from in vitro experiments are gathered to make educated decisions for the best possible CPB circuit selection prior to clinical use of such systems.3–6 Our main concern of this clinical study is that the authors have not stated the rationale for eliminating the arterial filter for any of the patients, along with the lack of neuromonitoring during and after CPB using a transcranial Doppler (TCD). The authors pointed out the significant differences between emboli detection and classification systems by different manufacturers, but the major limitation of these existing systems is the lack of quantification of emboli in patients. Therefore, TCD must be used to quantify the number of microemboli in the middle cerebral artery. It is a well-established device, used over several decades. Despite the authors’ claim about the number of emboli on the venous line, we have already documented that “initiation of CPB may be a key offender and may result from air in the venous line.”7 We agree with the authors about the negative impact of cardiotomy suction on microemboli generation. During the past 10 years in our institution, we have used a secondary reservoir for pump suckers for minimizing microemboli generation in all patients below 12 kg.8 Routine use of an
arterial filter along with a secondary reservoir for pump suckers may minimize the number of microemboli delivered to neonatal and pediatric patients during CPB procedures. In addition, we highly recommend conducting in vitro evaluation of any new circuit components prior to suggesting randomized clinical trials. Declaration of conflicting interest The authors declare that there is no conflict of interest.
Funding This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
References 1. Issit R, Roberson A, Cross N, et al. Clinical experience with Affinity PixieTM oxygenation system in paediatric and infant patients. Perfusion 2014; 29: 194–198. 2. Wang S, Ündar A. Translational research is a necessity for selecting the best components of the extracorporeal
1Department
of Pediatrics, Penn State Hershey Pediatric Cardiovascular Research Center, Hershey, PA, USA 2Department of Surgery, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, PA, USA 3Department of Bioengineering, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, PA, USA 4Perfusion Department, Penn State Heart and Vascular Institute, Penn State Milton S. Hershey Medical Center, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, PA, USA Corresponding author: Akif Ündar Professor of Pediatrics Surgery and Bioengineering Department of Pediatrics Penn State Hershey College of Medicine,—H085 500 University Drive P.O. Box 850 Hershey, PA 17033-0850 USA. Email: [email protected]
Downloaded from prf.sagepub.com at UNIVERSITE DE MONTREAL on June 11, 2015
173
Ündar et al. circuitry for neonatal and pediatric CPB patients [Letter]. Perfusion 2013; 28: 171–172. 3. Dogal NM, Mathis RK, Lin J, Qiu F, Kunselman A, Ündar A. Evaluation of three hollow-fiber membrane oxygenators without integrated arterial filters for neonatal cardiopulmonary bypass. Perfusion 2012; 27: 132–140. 4. Lin J, Dogal NM, Mathis RK, Qiu F, Kunselman A, Ündar A. Evaluation of Quadrox-i and Capiox FX neonatal oxygenators with integrated arterial filters in eliminating gaseous microemboli and retaining hemodynamic properties during cardiopulmonary bypass. Perfusion 2012; 27: 235–243. 5. Mathis RK, Lin J, Dogal NM, et al. Evaluation of four pediatric cardiopulmonary bypass circuits in terms of
perfusion quality and capturing gaseous microemboli. Perfusion 2012; 27: 470–479. 6. Strother A, Wang S, Kunselman AR, Ündar A. Handling ability of gaseous microemboli of two pediatric arterial filters in a simulated CPB model. Perfusion 2013; 28: 244– 252. 7. Clark JB, Qui F, Guan Y, Woitas KR, Myers JL, Ündar A. Microemboli detection and classification during pediatric cardiopulmonary bypass. World J Pediatr Congenit Heart Surg 2011; 2: 111–114. 8. Ündar A, Palanzo D, Wang S. Using a secondary reservoir for pump suckers to avoid the generation of foam during CPB procedures in pediatric patients. [Invited commentary]; Perfusion 2012; 27: 556–558.
Downloaded from prf.sagepub.com at UNIVERSITE DE MONTREAL on June 11, 2015
PRF0010.1177/0267659114550231PerfusionÜndar et al.
Letter to the Editor
Is it safe to conduct CPB procedures without arterial filters in neonatal and pediatric patients?
Perfusion 2015, Vol. 30(2) 172–173 © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0267659114550231 prf.sagepub.com
A Ündar,1–4 S Wang,1 D Palanzo4 and LD Baer4
Sir, We have read the article entitled “Clinical experience with Affinity PixieTM oxygenation system in paediatric and infant patients” by Issitt and co-workers with great interest.1 The authors stated that “The PixieTM oxygenator proved effective at flows up to 2.5 L/min, with airhandling capabilities comparable with other oxygenators” and “.., therefore, that further testing in a randomised controlled fashion between the PixieTM and competitor oxygenators should be undertaken in a clinical, in vivo setting to establish relative functionality.” It is our opinion that, to select the best possible circuit components for the CPB procedure, in vitro evaluation should be done prior to any in vivo studies, in particular, prior to suggesting randomized clinical trials.2 Although in vitro evaluations cannot replicate the clinical scenarios, invaluable scientific data from in vitro experiments are gathered to make educated decisions for the best possible CPB circuit selection prior to clinical use of such systems.3–6 Our main concern of this clinical study is that the authors have not stated the rationale for eliminating the arterial filter for any of the patients, along with the lack of neuromonitoring during and after CPB using a transcranial Doppler (TCD). The authors pointed out the significant differences between emboli detection and classification systems by different manufacturers, but the major limitation of these existing systems is the lack of quantification of emboli in patients. Therefore, TCD must be used to quantify the number of microemboli in the middle cerebral artery. It is a well-established device, used over several decades. Despite the authors’ claim about the number of emboli on the venous line, we have already documented that “initiation of CPB may be a key offender and may result from air in the venous line.”7 We agree with the authors about the negative impact of cardiotomy suction on microemboli generation. During the past 10 years in our institution, we have used a secondary reservoir for pump suckers for minimizing microemboli generation in all patients below 12 kg.8 Routine use of an
arterial filter along with a secondary reservoir for pump suckers may minimize the number of microemboli delivered to neonatal and pediatric patients during CPB procedures. In addition, we highly recommend conducting in vitro evaluation of any new circuit components prior to suggesting randomized clinical trials. Declaration of conflicting interest The authors declare that there is no conflict of interest.
Funding This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
References 1. Issit R, Roberson A, Cross N, et al. Clinical experience with Affinity PixieTM oxygenation system in paediatric and infant patients. Perfusion 2014; 29: 194–198. 2. Wang S, Ündar A. Translational research is a necessity for selecting the best components of the extracorporeal
1Department
of Pediatrics, Penn State Hershey Pediatric Cardiovascular Research Center, Hershey, PA, USA 2Department of Surgery, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, PA, USA 3Department of Bioengineering, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, PA, USA 4Perfusion Department, Penn State Heart and Vascular Institute, Penn State Milton S. Hershey Medical Center, Penn State Hershey College of Medicine, Penn State Hershey Children’s Hospital, Hershey, PA, USA Corresponding author: Akif Ündar Professor of Pediatrics Surgery and Bioengineering Department of Pediatrics Penn State Hershey College of Medicine,—H085 500 University Drive P.O. Box 850 Hershey, PA 17033-0850 USA. Email: [email protected]
Downloaded from prf.sagepub.com at UNIVERSITE DE MONTREAL on June 11, 2015
173
Ündar et al. circuitry for neonatal and pediatric CPB patients [Letter]. Perfusion 2013; 28: 171–172. 3. Dogal NM, Mathis RK, Lin J, Qiu F, Kunselman A, Ündar A. Evaluation of three hollow-fiber membrane oxygenators without integrated arterial filters for neonatal cardiopulmonary bypass. Perfusion 2012; 27: 132–140. 4. Lin J, Dogal NM, Mathis RK, Qiu F, Kunselman A, Ündar A. Evaluation of Quadrox-i and Capiox FX neonatal oxygenators with integrated arterial filters in eliminating gaseous microemboli and retaining hemodynamic properties during cardiopulmonary bypass. Perfusion 2012; 27: 235–243. 5. Mathis RK, Lin J, Dogal NM, et al. Evaluation of four pediatric cardiopulmonary bypass circuits in terms of
perfusion quality and capturing gaseous microemboli. Perfusion 2012; 27: 470–479. 6. Strother A, Wang S, Kunselman AR, Ündar A. Handling ability of gaseous microemboli of two pediatric arterial filters in a simulated CPB model. Perfusion 2013; 28: 244– 252. 7. Clark JB, Qui F, Guan Y, Woitas KR, Myers JL, Ündar A. Microemboli detection and classification during pediatric cardiopulmonary bypass. World J Pediatr Congenit Heart Surg 2011; 2: 111–114. 8. Ündar A, Palanzo D, Wang S. Using a secondary reservoir for pump suckers to avoid the generation of foam during CPB procedures in pediatric patients. [Invited commentary]; Perfusion 2012; 27: 556–558.
Downloaded from prf.sagepub.com at UNIVERSITE DE MONTREAL on June 11, 2015
