Research Article
A Dynamic Model of Rescuer Parameters for Optimizing
Blood Gas Delivery during Cardiopulmonary Resuscitation
Ali Jalali ,
1
Allan F. Simpao ,
2
JorgeA.G´ alvez,
2
Robert A. Berg,
2
Vinay M. Nadkarni,
2
and Chandrasekhar Nataraj
3
1
Health Informatics Core, Johns Hopkins All Children’s Hospital, 501 6th Avenue South, St. Petersburg, FL 33701, USA
2
Department of Anesthesiology & Critical Care Medicine, Children’s Hospital of Philadelphia,
Perelman School of Medicine at the University of Pennsylvania, 3401 Civic Center Blvd., Philadelphia, PA 19104, USA
3
Villanova Center for Analytics of Dynamic Systems, Department of Mechanical Engineering, Villanova University,
Villanova, PA 19085, USA
CorrespondenceshouldbeaddressedtoAliJalali;jalali@jhmi.edu
Received 29 August 2018; Accepted 11 November 2018; Published 29 November 2018
AcademicEditor:omasDesaive
Copyright©2018AliJalalietal.isisanopenaccessarticledistributedundertheCreativeCommonsAttributionLicense,which
permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Introduction.equalityofcardiopulmonaryresuscitation(CPR)hasbeenshowntoimpactpatientoutcomes.However,post-CPR
morbidityandmortalityremainhigh,andCPRoptimizationisanareaofactiveresearch.OneapproachtooptimizingCPRinvolves
establishingreliableCPRperformancemeasuresandthenmodifyingCPRparameters,suchascompressionsandventilatorbreaths,
toenhancethesemeasures.WeaimedtodefineareliableCPRperformancemeasure,optimizetheCPRperformancebasedonthe
definedmeasureanddesignadynamicallyoptimizedschemethatvariesCPRparameterstooptimizeCPRperformance. Materials
and Methods.Weselectedtotalbloodgasdelivery(systemicoxygendeliveryandcarbondioxidedeliverytothelungs)asanobjective
functionformaximization.CPRparametersweredividedintothreecategories:rescuerdependent,patientdependent,andconstant
parameters. Two optimization schemes were developed using simulated annealing method: a global optimization scheme and a
sequential optimization scheme. Results and Discussion.VariationsofCPRparametersoverCPRsequences(cycles)wereanalyzed.
Across all patient groups, the sequential optimization scheme resulted in significant enhancement in the effectiveness of the CPR
procedurewhencomparedtotheglobaloptimizationscheme. Conclusions.Ourstudyillustratesthepotentialbenefitofconsidering
dynamic changes in rescuer-dependent parameters during CPR in order to improve performance. e advantage of the sequential
optimization technique stemmed from its dynamically adapting effect. Our CPR optimization findings suggest that as CPR
progresses,thecompressiontoventilationratioshoulddecrease,andthesequentialoptimizationtechniquecanpotentiallyimprove
CPR performance. Validation in vivo is needed before implementing these changes in actual practice.
1. Introduction
Cardiopulmonary resuscitation (CPR) involves delivering
chest compressions and positive pressure ventilation to car-
diac arrest victims to maintain circulatory blood flow and
oxygen delivery [1]. Studies have shown that the quality of
CPRcanimpactpost-CPRoutcomesandsurvival[2–7].CPR
optimizationremainsanactivetopicofresuscitationresearch
becausesurvivalratesforpost-CPRhospitalinpatientsremain
low [8]. Various approaches have been proposed to modify
and optimize the CPR process. Simultaneous ventilation and
compressionaswellasinterposedabdominalcompressionare
two examples of CPR modification [9–11].
Another approach to optimizing CPR involves defining
and establishing reliable, appropriate CPR performance
measures and then modifying CPR parameters to enhance
these measures. Brain ischemia is a primary contributor to
postarrest morbidity; thus, oxygen delivery and carbon di-
oxideelimination(end-tidalcarbondioxide[ETCO
2
])have
been established as important factors for measuring CPR
performance [12, 13]. Other performance measures include
meancoronaryperfusionpressure(CPP),nitricoxide(NO),
and balance of systemic and pulmonary perfusion with
ventilation [14–17]. e CPR compression to ventilation
ratiohasbeenshowntobeaCPRparameterthatinfluences
postarrest outcomes [18–21]. Another important CPR
Hindawi
Computational and Mathematical Methods in Medicine
Volume 2018, Article ID 3569346, 6 pages
https://doi.org/10.1155/2018/3569346