A Study of Cerebral Performance Categories Based on Initial Rhythm and Resuscitation Time Following In-Hospital Cardiac Arrest in a State Hospital in Turkey

Copyright © 2018 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution License (http:// creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1. Background Every year, hundreds of thousands of people are saved after heart and/or respiratory arrest (cardiopulmonary arrest [CPA] with cardiopulmonary resuscitation [CPR]).1 However, ischemia and subsequent reperfusion result in serious brain damage despite improvement in the cardiac function of patients. Unfortunately, a satisfactory improvement in brain function cannot be achieved in most cases. Therefore, successful resuscitation should be in the form of both heart and brain resuscitation. In this context, the best post-resuscitation measurement involves an assessment of brain function.2,3 The neurological condition varies between complete recovery and brain death.4,5 Various measures are available to evaluate brain function after resuscitation. The Utstein-style guidelines recommend the use of the cerebral performance category (CPC), a 5-point scale that tries to combine functional and cognitive domains to provide an assessment of brain healing.2,6,7 Several studies have demonstrated the effects of initial rhythms and resuscitation durations on CPC for shortor long-term survival and the rate of return of spontaneous circulation (ROSC) after CPR.8-12

CPR.The patients survived for at least 24 hours and were discharged after treatment in the Konya Numune Hospital between June 2013 and June 2015.Consent to conduct this study was obtained from the Selcuk University Faculty of Medicine Ethical Committee (Ref no: 2017-100).The CPC values of the studied patients were followed up for 2 years after discharge.Subjects who were younger than 18 years died before discharge from the hospital and, hence, were excluded from the study.The follow-up results are shown in Figure 1 as a flow chart.
In-hospital resuscitation for these patients was performed in accordance with current advanced life support protocols (2010 European Resuscitation Council Guideline).Demographic data, such as age and sex of the cases and clinical parameters related to CPR, were recorded.
The information obtained from the doctors and patients' relatives was evaluated by the neurology specialist.Neurological status measurements were evaluated by the neurology specialist using the CPC, a 5-category scale based on the initial rhythm (asystole/pulseless electrical activity and ventricular fibrillation/pulseless ventricular tachycardia) and resuscitation time (0-14 minutes and 15-30 minutes) by calling patients or their relatives at the 6th, 12th, 18th, and 24th months after discharge from the hospital.The 5 categories of the CPC are: CPC 1, conscious and alert with good cerebral performance; CPC 2, conscious and alert with moderate cerebral performance; CPC 3, conscious with severe cerebral disability; CPC 4, comatose or in persistent vegetative state; and CPC 5, brain dead, circulation preserved.For those patients who did not give enough information, the follow-up information was obtained from the doctors who worked for homehealth services.CPC 1 and 2 were classified as favorable neurological outcomes, whereas CPC 3, 4, and 5 were evaluated as poor outcomes.
Analyses in the study were done using SPSS 20.0 software (SPSS, IL, USA).Continuous and categorical variables were presented in tables and graphs by subtracting descriptive measures.Continuous variables were expressed as mean ± standard deviation (SD), whereas categorical variables were expressed as frequencies and percentage ratios.Cross tables were prepared, and the chi-square test was used to determine any relationships between categorical variables.A P value (Fisher exact test) less than 0.05 was considered statistically significant for all analyses.

Results
This retrospective case-controlled study included 44 patients who were discharged and who survived 24 hours (n = 103) from ROSC (n = 135) from a total of 390 CPR patients between 2011 and 2013, and their neurological statuses were assessed between June 2013 and June 2015.The flow chart of the study is shown in Figure 1.
The socio-demographic and clinical values of the subjects are listed in Table 1.CPR starting time was 1.8 ± 0.5 minutes.CPR was applied to 29 patients for 0-14 minutes and to 15 patients for 15-30 minutes.No patients underwent CPR for 30 minutes or more.At the time of CPA, 10 patients had first rhythm asystole/PEA and 34 patients had VF/PVT.Moreover, 135 patients had the ROSC, and 103 patients survived for more than 24 hours.
During the course of this prospective clinical study, 44 patients survived and were discharged after successful CPR.At the time of discharge, the neurological evaluation scores of 10 patients (22.6%) were CPC 1-2 and of 34 patients (77.4%) were CPC 3-4 according to the initial rhythms in CPA asystole/NEA and VF/PVT, respectively.

Discussion
This study found that, when the resuscitation time and the initial cardiac rhythms during resuscitation were considered, long-term CPC scores did not differ in patients who were discharged from the hospital following in-hospital CPR.
It is well known that most patients who have cardiac resuscitation at the hospital cannot be discharged. 14A successful CPR depends on the presence of basic and advanced life support systems, the ability to perform early defibrillation, and the quality of CPR intervention. 15fter an in-hospital cardiac arrest, survival at discharge is approximately 15%-20%. 16,17In Turkey, this rate is about 11%-25.7%. 18,19he debate on the most useful approach to assess the outcome of sudden cardiac arrest is ongoing. 3Although the purpose of the data and studies is balanced, the results of some studies indicate that CPC is a measure of longterm longevity and is useful for obtaining long-term resuscitation results. 2,20Moreover, these findings support the use of the CPC following neurological prognosis when post-arrest patients are discharged.For example, those classified as CPC 1-2 have shown better survival rates than those classified as CPC 3-4.The life expectancy of postarrest patients with different CPC scores during discharge is significantly different.
After discharge, long-term neurological results of survivors after a cardiac arrest are better than those with CPC scores of 1-2 and CPC scores of 3-5.That is, CPC 3 and CPC 4 scores are associated with worse long-term outcomes in patients after CPA.Thus, CPC scores may help in further studies to predict necessary controls and treatments of post-arrest patients after discharge from the hospital.
Moreover, the changes in CPC scores were not statistically significant according to the time periods in this study, but more changes were observed from the 12th month to the 18th month.
This novel study involved the longest neurological follow-up periods of patients who survived CPA and were discharged from the hospital.
It is believed that the decrease in neurological performance after the 12th month in patients who had the initial rhythms of VF-PVT and better resuscitation times (e.g., 0-14 minutes) may be related to the treatmentrelated disorders of their primary diseases, lack of home care, or the appearance of new diseases.
The current study had some limitations.First, although the study was a prospective clinical study, only 2-year-old data from a single center was used.Hence, the lack of a study population prevented conducting more valuable statistical studies.Second, the concept of therapeutic hypothermia could not be fully applied to CPA patients when the study was planned and performed.Third, primary disease follow-ups of the patients could not be done after their discharge.Fourth, the CPC scoring system was used in the study; however, some other criteria could be used as well.Fifth, since most studies have been performed on outhospital cardiac arrest cases, the number of neurological outcomes of in-hospital cardiac arrests after discharge in the literature was insufficient.

Conclusion
The survivors of cardiac arrest were found to have deteriorated neurological outcomes after discharge during a 2-year period in this study.These results did not depend on the duration of arrest or the first rhythm and resuscitation period.The present results were contrary to the findings of existing studies.It suggested that the postdischarge follow-up and treatments of the patients were not enough.Therefore, it is recommended that adequate training be given to the families or the caregivers of patients.It is thought that the provision of pre-discharge palliative care services to patients with the help of health care professionals may improve the neurological results after discharge.

Figure 1 .
Figure 1.Flowchart of a Case-Control Clinical Study Follow-up.CPR, cardiopulmonary resuscitation; CPC, cerebral performance category; ROSC, return of spontaneous circulation.

Table 2 .
Number of Patients According to the Initial Rhythm in CPR and 2-Year Neurological Evaluation Scores

Table 3 .
Number of Patients Who Underwent Resuscitation Between 0-14 and 15-30 Minutes According to the CPR Period and 2-Year Neurological Evaluation Scores * Patients who survived after CPR but did not survive to discharge are not shown in Table