Predicting possibility of mortality in critically ill patients with neurological diseases by using Simplified Acute Physiology Score Ⅱ / 中华神经科杂志

ABSTRACT

Objective To evaluate feasibility and reliability of using Simplified Acute Physiology Score Ⅱ (SAPS Ⅱ)in predicting mortality in critically ill patients with neurological diseases.Methods All 653 patients hospitalized in neurological intensive care unit (N-ICU) from Jan 2005 to Dec 2007 were retrospectively studied.SAPSⅡ scores were scaled upon admission at 24,48 and 72 h,and possibility of hospital mortality (PHM) was calculated based on SAPS Ⅱ score.Neurological diseases diagnosis made initially at time of hospitalization was classified into five categoriesintracranial hemorrhage,cerebral infarction,neurologic infection,neuromuscular diseases and other neurologic diseases.At each of four time points,the SAPSⅡscores were compared between the survival group and death group,and the relationship of SAPS Ⅱ score and prognosis were analyzed.The calibration of the SAPS Ⅱ were accessed with the Hosmer-Lemeshow goodness-of-fit chi-squared statistic and the discrimination with area under the receiver operating characteristic curve (AUROC).Multivariate logistic regression was used to analyze the relationship between disease category and prognosis.Results SAPS Ⅱ scores in the death group (46.53±12.22,47.28±13.84,48.58±14.18 and 49.06±14.61)at each time point were significantly higher than those in the survival group (34.70±11.78,30.28±12.24,29.79±12.36 and 29.69±12.96;t=11.12,14.02,14.43 and 13.49 at 0,24,48 and 72 h,respectively,P＜0.01).Furthermore,univariate logistic regression analyses demonstrated that SAPS Ⅱ score was correlated with prognosis (OR=1.080,1.100,1.109,1.100 at 0,24,48 and 72 h,respectively,P＜0.01).The scores at 48 and 72 h were more accurate in predicting mortality.SAPS Ⅱ had good calibration at each time points (x2=5.305,7.557,6.369 and 8.540,P＞0.05),however,the consistency of expected mortality with observed mortality was satisfactory only at 48 and 72 h(82.6%,83.4%),so was the discrimination ( AUROC=0.825,0.847 respectively).There was no correlation between disease categories and outcome.Conclusion SAPS Ⅱ scoring,best evaluated at 48 and 72 h after hospitalization,can be used as a reliable predictor of probability of mortality in patients hospitalized in N-ICU and prediction can be applied in these patients with all different neurology diseases.