RESUMEN
<p><b>OBJECTIVE</b>To investigate the risk factors in postoperative cognitive dysfunction (POCD) induced by patient self-controlled intravenous analgesia (PCIA).</p><p><b>METHODS</b>A case-control study included 103 patients with POCD(P group), assessed by Mini-Mental-State test and 103 cognitive normal controls (NP group). The cases and controls were matched for age, gender,history of operation and PCIA volume dose. The relationship between POCD and various factors was analyzed by univariate and multivariate analysis. Spss 11.5 of statistical software was used for data analysis.</p><p><b>RESULTS</b>Data from univariate analysis showed that the history of cerebral trauma, education level and VAS score had significant differences between P group and NP group. Multivariate analysis conformed that the history of cerebral trauma, VAS score and education level were significantly related to POCD induced by PCIA and their ORs (95% CI) were 4.261 (1.344-13.508), 2.364 (1.209-4.624), 0.312 (0.170-0.573) respectively.</p><p><b>CONCLUSION</b>Patient's history of cerebral trauma and low VAS score were independent risk factors of POCD induced by PCIA and high education level seemed to be a protective factor.</p>