The nitrous oxide-induced psychotic disorder is a type of psychotic phenomenon that occurs during or immediately after using nitrous oxide and is characterized by vivid hallucinations, psychomotor disturbances, disturbance of consciousness, etc. Although nitrous oxide can cause various neuropsychiatric symptoms, there are few reports of nitrous oxide-induced psychotic disorder featured with catatonia and convulsions. Given the rarity of this case in clinical settings, we present the following case report and review relevant literature to help the identification and treatment of this disease.

The nitrous oxide-induced psychotic disorder is a type of psychotic phenomenon that occurs during or immediately after using nitrous oxide and is characterized by vivid hallucinations, psychomotor disturbances, disturbance of consciousness, etc. Although nitrous oxide can cause various neuropsychiatric symptoms, there are few reports of nitrous oxide-induced psychotic disorder featured with catatonia and convulsions. Given the rarity of this case in clinical settings, we present the following case report and review relevant literature to help the identification and treatment of this disease.

Objective To investigate the status quo of the off-label use in patients with major mental disorders in a tertiary psychiatric hospital and to analyze its relevant risk factors,so as to provide the basis for establishing the off-label use norm.Methods The data of inpatients with major mental disorders (schizophrenia,bipolar disorder and depression) were collected from electronic medical records system in the Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital).The incidence and categories of off-label use were analyzed by descriptive analysis.The chi-square test and logistic regression analysis were used to analyze factors such as age,gender,diagnosis,the number of prescribed psychotropic drugs,physician title,etc.Results A total of 2 371 patients and 10 794 prescriptions were collected and analyzed.The incidence of off-label use was 80.43％ (1 907/2 371) and 42.46％ (4 583/10 794) in patients and prescriptions,respectively.The main categories and constituent ratio of off-label use were indications (89.16％,4 086/4 583),dosage (4.63％,212/4 583),population and age (0.31％,14/4 583),while there were 5.91％ (271/4 583) prescriptions contain 2 or more different categories.The off-label use was widespread among different types of psychotropic drugs,mental disorders and clinical departments.The risk factors were the number of prescribed psychotropic drugs (Wald=177.218,P＜0.01),the diagnosis of mental disorders (Wald=35.320,P＜0.01) and physician title (Wald=8.667,P=0.003).Conclusion Off-label use is common in patients in the tertiary psychiatric hospital,involving different kinds of psychotropic drugs,mental disorders and clinical departments.The primary category of off-label use is indications.

Objective To investigate the status quo of the off-label use in patients with major mental disorders in a tertiary psychiatric hospital and to analyze its relevant risk factors,so as to provide the basis for establishing the off-label use norm.Methods The data of inpatients with major mental disorders (schizophrenia,bipolar disorder and depression) were collected from electronic medical records system in the Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital).The incidence and categories of off-label use were analyzed by descriptive analysis.The chi-square test and logistic regression analysis were used to analyze factors such as age,gender,diagnosis,the number of prescribed psychotropic drugs,physician title,etc.Results A total of 2 371 patients and 10 794 prescriptions were collected and analyzed.The incidence of off-label use was 80.43％ (1 907/2 371) and 42.46％ (4 583/10 794) in patients and prescriptions,respectively.The main categories and constituent ratio of off-label use were indications (89.16％,4 086/4 583),dosage (4.63％,212/4 583),population and age (0.31％,14/4 583),while there were 5.91％ (271/4 583) prescriptions contain 2 or more different categories.The off-label use was widespread among different types of psychotropic drugs,mental disorders and clinical departments.The risk factors were the number of prescribed psychotropic drugs (Wald=177.218,P＜0.01),the diagnosis of mental disorders (Wald=35.320,P＜0.01) and physician title (Wald=8.667,P=0.003).Conclusion Off-label use is common in patients in the tertiary psychiatric hospital,involving different kinds of psychotropic drugs,mental disorders and clinical departments.The primary category of off-label use is indications.

Objective To assess the clinical effect of Percutaneous transforaminal endoscopic spinal surgery for central lumbar spinal stenosis.Methods Total 92 patients (44 males and 48 females with average age of 68.6± 12.4 years) with central lumbar spinal stenosis were enrolled in our study during February 2012 and July 2016.All patients were treated with Percutaneous transforaminal endoscopic spinal surgery.Clinical and Radiographic evaluation were investigated on 1 week,3 months,6 months,12 months postoperatively and final follow-up.Visual analogue scale (VAS) for low back pain and leg pain,Oswestry disability index(ODI) for low back pain were used to evaluate the clinical efficacy of surgery.Pre and postoperative Dural sac cross sectional area(DSCA) was measured.And the correlation between changes of DSCA and clinical efficacy was analyzed.Results The operation time was 45-1 15 min.The mean operation time was 75±15 min.the mean blood loss was 15±5 ml (range 8-50 ml).All patients were followed for 12-46 months (24.5±5.3 months).VAS for low back pain,VAS for leg pain,and OD1 were significantly improved from 6.75± 1.28,7.79± 1.15 and 39.82％ ±5.06％ preoperatively to 2.21± 1.08,2.16± 1.14 and 9.82％ ±3.69％ at the latest follow-up.Dural sac cross sectional area significantly increased from 55.35±12.18 mm2 preoperatively to (102.36±15.38) mm2 at the latest follow-up.Correlation coefficient with DSCA change was-0.480 for ODI change,-0.612 for VAS(low back pain) change,-0.637 for VAS (leg pain)(P ＜ 0.05);obvious positive correlation existed between the change of DSCA and patient's clinical efficacy.It showed that the change of DSCA was positively correlated with the patient's clinical efficacy.The clinical results were excellent in 56 cases.good in 29,fair in 4,and poor in 3 based on the MacNab criteria.92.39％ demonstrated a good-to-excellent outcome.One case occurred cauterizing syndrome,3 cases of recurrence,and 2 cases of Dural tear.There was no severe vascular or nerve injury.Conclusion Percutaneous transforaminal endoscopic spinal surgery provides a new minimally invasive treatment for central lumbar spinal stenosis.It is safe and effective.It is found that the change of DSCA is positively correlated with the clinical efficacy of surgery.