Introduction: Carbon monoxide (CO) poisoning results in delayed neuropsychological sequel (DNS) in some patients after recovery of acute symptoms. DNS symptoms change from slight impairment in attention, memory and visuospatial skills to severe neuropsychiatric disorders. The aim of this study is to assess the frequency and clinical features of DNS in patients with CO poisoning.
Method: In this study, retrospective patient charts were reviewed who applied to hyperbaric oxygen therapy (HBO) due to CO poisoning. Parent-report of children’s depression inventory (PR-CDI), child-report children’s depression inventory (CR-CDI), state-trait anxiety inventory for children (STAIC), digit span subtest of Wechsler intelligence scale for children-revised (WISC-R), child behavior checklist, raven standard progressive matrices test (RSPM), verbal and non-verbal cancellation tests were applied. Two interviews were conducted, first initially; the second one is one month later. Differences were compared between neuropsychiatric symptoms and symptoms levels of inventories, checklist and tests, which were applied initially and at first month. In addition, impact of COHb levels, duration of exposure to CO, total duration between beginning of poisoning and starting to HBO treatment, experience of syncope and number of HBO session on neuropsychological assessment scales were examined. SPSS, version 15.0 was used for the statistical analysis. Mann-Whitney U test was used for comparison of differences between groups. The correlation between variables was analyzed with the Pearson correlation test. P values less than.05 were considered significant.
Results: In this study data of 27 patients were assessed. Their ages ranged from 6 to 18 years, with a mean of 11.8±2.7 years. Only one patient had DNS symptoms including tinnitus and headache. It was revealed that COHb levels did not have effect on neuropsychological assessment scales, but experience of syncope had effect on anxiety symptom levels. Also behavioral problems worsened as number of HBO session increase, prolonged time before HBO session have negative effects on attention.
Conclusions: It is revealed that duration of exposure to CO, total duration between beginning of poisoning and starting to HBO treatment and number of HBO session had negative effects on psychiatric symptoms, attention and behavioral problems.