[Meta-analysis of prognostic tests in neonates over 35-week gestational age with hypoxic-ischemic encephalopathy]

To explore the prognostic value of currently used clinical tests in neonatal patients over 35-week gestational age with perinatal asphyxia and hypoxic-ischemic encephalopathy (HIE).

"Neonate""hypoxic-ischemic encephalopathy " and "prognostic test" were used as key words. Searches were made on the databases of PubMed, EMBASE, CNKI and WanFang for studies published between January 1980 and December 2012. Studies were included if they (1) evaluated outcome in over 35-week gestational age neonates with perinatal asphyxia or HIE; (2) reported outcomes at minimal follow-up age of 18 months; (3) confirmed neurodevelopment with favorable or adverse outcomes. RevMan 5.2 software 1.4 was used for meta-analysis. And the evaluation criteria of each study were employed to assess and analyze the results comprehensively.

Among 260 relevant studies, 20 were included. There are 7 tests contented our inclusion criteria: amplitude-integrated electroencephalography (aEEG), magnetic resonance imaging (MRI:T1/T2 weighted imaging, diffusion weighted imaging (DWI), apparent diffusion coefficient (ADC), magnetic resonance spectroscopy (MR S)), cerebral ultrasound (CUS) and HIE stage. The most promising tests were aEEG: sensitivity 0.936 (95%CI: 0.897-0.964) ; specificity 0.884 (95%CI: 0.836- 0.921). In imaging, T1/T2-weighted MRI sensitivity 0.913 (95%CI: 0.850-0.956), specificity 0.630 (95%CI: 0.544-0.711); diffusion weighted MRI sensitivity 0.933 (95%CI:0.817-0.956), specificity 0.694 (95%CI: 0.546-0.817); ADC sensitivity 0.778 (95%CI: 0.664-0.867) , specificity 0.971 (95%CI: 0.898-0.996); MRS sensitivity 0.918 (95%CI: 0.804-0.977), specificity 0.642 (95%CI: 0.515-0.755). CUS sensitivity 0.683 (95%CI: 0.519-0.819), specificity 0.459 (95%CI: 0.295-0.631). HIE stage sensitivity 0.967 (95%CI: 0.924-0.989) , specificity 0.314 (95%CI: 0.241-0.394).

These evidence suggests an important role for aEEG, MRI (T1/T2-weight, DWI, ADC), CUS and HIE stage. The sensitivity and specificity of aEEG are both relatively high; HIE stage has good sensitivity; in imaging, T1/T2-weight,DWI and MRS yield better sensitivity while ADC has the best specificity. Mild hypothermia treatment reduces the predictive value of evaluation system.Each test has its advantages and disadvantages. Thus an integrated use of a variety of prognostic tests centering on clinical neurological assessment is optimal.