All subjects were divided into two groups, consisting of 13 cases who developed DNS and 66 cases who did not, and were reviewed for clinical symptoms and laboratory findings at admission to the emergency department, circumstances of injury, treatment received during the acute phase, and other information to the extent check details available in the emergency department setting. Patient medical records were retrospectively reviewed, Inhibitors,research,lifescience,medical and patients who

developed DNS and patients who did not develop DNS were compared in terms of 16 items: gender, age, location of exposure, estimated duration of exposure, whether or not the patient was transported from another hospital, severity of impaired consciousness (i.e., Japan Coma Scale [JCS] score) when the patient was first seen at a hospital [19], CO-Hb level when the patient was first seen at Inhibitors,research,lifescience,medical a hospital, white blood cell (WBC) count and CK, CK-MB, and LDH levels on the day the patient was seen, whether or not there were abnormal findings from a head CT scan when the patient was first seen, whether or not HBO therapy was administered on the day the patient was seen, diagnostic category according Inhibitors,research,lifescience,medical to “Mental and behavioural disorders” in the International Classification of Diseases, Tenth Revision (ICD-10) [20], duration of hospital stay, and number of sessions of HBO therapy. In

addition, the patients were assessed in terms of their psychiatric Inhibitors,research,lifescience,medical symptoms using a Japanese version (by Kitamura, et al.) [21] of the Oxford University version of the Brief Psychiatric Rating Scale (BPRS), and were also investigated in terms of their general psychiatric symptoms and abilities of daily living using a Japanese translation by Kitamura, et al. of the Global Assessment Scale (GAS) [22]. Furthermore, the patients’ life events prior to their attempted suicide were assessed using the Life Change Units (LCU) of the Holmes Social Readjustment Rating Scale [23]. Note that JCS scores and CO-Hb levels used

in this study were those obtained at the first medical institution, not necessarily the Hospital, to which each patient was admitted in emergency, Inhibitors,research,lifescience,medical since quite a few cases were transferred to the Hospital under oxygen administration after consultation at another medical institution. Assessment and diagnosis of each review item were performed by an emergency psychiatrist or the Hospital’s psychiatrist on duty. Statistical processing was performed using Tryptophan synthase SPSS 17.0J for Windows. Testing of mean values, ratios and JCS scores was conducted using one-way analysis of variance, a chi-square test and the Mann-Whitney U test, respectively. In all tests, the level of significance was 5%, with significance probabilities being expressed in numbers. This study is a chart review study and we did not obtain informed consent. Personally identifiable information was excluded from data. Consideration was given to the protection of personal information in the process of data management and processing.