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 categories:intracranial 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.