A Study On The Reliability Of INCNS Score In The Prognosis Of Comatose Patients

BackgroundAs the development of critical care medicine rapidly increases,new therapeutic treatments,such as mechanical ventilation and extracorporeal membrane oxygenation(ECMO)technology,have greatly improved the rescue success rate of critically ill patients.However,a considerably large number of patients are still in coma after being successfully rescued,so the prognosis of comatose patients has always been an important challenge in the medical field.The common methods for the prognosis of comatose patients include behavioral assessments,electrophysiological examinations,serum markers and brain images,etc.Although imaging and neuro-electrophysiology can quite accurately predict the prognosis of comatose patients,these technologies are far away from widespread usage in primary hospitals because of their high requirements.The behavioral assessment on the other hand are praised by many clinicians because it is simple,economical,and it could be done anywhere of any day.The behavioral assessment scales such as Glasgow Coma Scale(GCS),Full Outline of Un-Responsiveness Score(FOUR)are widely used for comatose patients in clinical practice.However,these scales still have their limitations are regards to the accuracy of predicting the prognosis of comatose patients.Previously,our research group has developed an assessment scale(containing 5 assessment domains: Inflammation,Nutrition,Consciousness,Neurological function,Systemic condition)for critically ill patients called the INCNS score,which exhibited strong predictive power in neurocritically-ill patients.But whether the INCNS could be used as a reliable tool to predict the outcomes of comatose patients is unclear.The purpose of this study is to verify the veracity and reliability of the INCNS score for the prediction of NICU mortality and of the 3-month functional outcome and mortality in comatose patients.MethodsIn this study,data of the comatose patients admitted to neurological ICU(NICU)from January 2013 to January 2019 were collected for validation.The 3-month functional outcomes were evaluated using modified Rankin Scale(m RS).By using the receiver operating characteristics curve(ROC)analysis,we compared the INCNS score with GCS,FOUR and Acute Physiology and Chronic Health Evaluation Ⅱ(APACHE Ⅱ)for assessment of the predictive performance of 3-month functional outcome and mortality and NICU mortality performed at 24 h and 72 h after having admitted in NICU.We further compared the accuracy,sensitivity(Se),specificity(Sp),positive predictive value(PPV),negative predictive value(NPV)and the number of patients correctly classified(CC)between INCNS and APACHE Ⅱ.In addition,ROC analysis was used to verify the prognostic ability of neural function and systemic function subcategories of the INCNS score.All scores were performed at 24 hours and 72 hours after admission.ResultsThe data of 271 comatose patients were collected for this assessment.The area under the receiver operating characteristic curve(AUC)of the 24 h and 72 h INCNS for the 3-month prognosis were 0.766(95% CI: 0.711-0.815)and 0.824(95% CI: 0.774-0.868),respectively.The INCNS score had a better predictive performance than GCS(24h: p <0.0001;72h: p < 0.0001)and FOUR score(24h: p = 0.0004;72h: p < 0.0001).However,there was no significant difference between INCNS and APACHE Ⅱ score in predicting functional outcome at 24 h(p = 0.1419)and 72 h(p = 0.0496).The AUC of 24 h and 72 h INCNS for NICU mortality assessment were 0.848(95% CI: 0.800-0.889)and 0.892(95%CI: 0.848-0.926).There was no significant difference between the INCNS score and APACHE Ⅱ(24h: p = 0.4257,72h: p = 0.3779)for the prediction of NICU mortality.However,compared with GCS(24h: p = 0.0001;72h: p = 0.0009)and FOUR score(24h:p = 0.0033;72h: p = 0.0115),the INCNS score showed better predictive ability.The AUC of 24 h and 72 h INCNS for the assessment of 3-month mortality after discharge from hospital were 0.811(95% CI: 0.760-0.856)and 0.832(95% CI: 0.782-0.874),respectively,and compared with APACHE Ⅱ,FOUR and GCS scores(APACHE Ⅱ24h: p = 0.0001,72h: p = 0.0012;FOUR score: 24h: p < 0.0001,72h: p < 0.0001;GCS score: 24h: p < 0.0001,72h: p < 0.0001;GCS score: 24h: p < 0.0001,72h: p < 0.0001),the INCNS score had a better predictive performance of mortality 3 months after discharge.By using the cut off value to analyze the accuracy,Se,Sp,PPV,NPV and CC of INCNS and APACHE Ⅱ,we found that the overall predictive accuracy of the INCNS score was better than the APACHE Ⅱ.We also compared the predictive power of neurological function and systemic functional subcategories of INCNS,and found that the predictive power of the neural function subcategories of INCNS was not better than that of the FOUR score,while the predictive ability of the systemic functional subcategories was better than that of the APACHE Ⅱ score.ConclusionsINCNS may be used to evaluate and predict NICU mortality,and the mortality and functional outcome 3 months after discharge,indicating the predictive ability of the INCNS score could be better than that of APACHE Ⅱ,FOUR and GCS.As admitted,the neural function subcategories of the INCNS score still needs further improvement,and its clinical applicability needs further verification.