BACKGROUND: Hyperbaric oxygen therapy has been considered as an effective therapy for prevention and cure of cerebral infarction traditionally.However, some scholars suggested that hyperbaric oxygen therapy could also result in cerebral infarction, although the mechanism is unclear.OBJECTIVE: To investigate the cause of cerebral infarction due to hyperbaric oxygen therapy.DESIGN: Case-control trial with patients as subjects.SETTING: Department of Hyperbaric Oxygen, Guangzhou General Hospital of Guangzhou Military Area Command of Chinese PLA.PARTICIPANTS: From December 1996 to March 1998, 192 inpatients receiving hyperbaric oxygen therapy were recruited into the trial from the Department of Hyperbaric Oxygen, Guangzhou General Hospital of Guangzhou Military Area Command of Chinese PLA. There were 127 males and 65 females aged 9-78 years. Patients admitted to the department of hyperbaric oxygen were eligible if they had hypoxia or ischemia induced disease and had no contraindication to hyperbaric oxygen therapy. Patients were recruited into the study regardless of the gender, and all patients and their family gave informed consent before enrollment. Patients were excluded if they did not receive hyperbaric oxygen therapy. According to the Diagnosis and Curing Criteria of Clinical Diseases, 6 patients developed into cerebral infarction during hyperbaric oxygen therapy, 3 males and 3 females, at the age of 51-76 years.METHODS: Patients were exposed to oxygen at 0.2 MPa in hyperbaric chamber used for many persons, and inhaled oxygen with a facemask once a day for 80 minutes with an interval of 10 minutes at the 40th minute. Ten days was considered as one course. Background and risk factors were analyzed in 6patients with cerebral infarction and 186 patients without cerebral infarction.MAIN OUTCOME MEASURES: Analysis of distribution of risk factors among cerebral infarction patients, and risk factor levels in patients without cerebral infarction.RESULTS: Among the 6 patients with cerebral infarction, hyperlipidemia was in all 6 cases, hypertension in 5 cases, primary cerebral infarction or hemorrhage in 5 cases, ≥ 60 years old or hyperviscosity in 4 cases, and diabetes mellitus in 1 case. Risk factor aggregation existed in the patients with over four risk factors. Of the 6 patients with cerebral infarction due to hyperbaric oxygen therapy, 5 cases had 4 risk factors and 1 had 5 risk factors. Of the 186 patients without cerebral infarction, 25 cases had 4 risk factors, and no case had 5 risk factors. The risk factor aggregation was relatively impossible (x2 = 54. 37, P ＜ 0. 05 ).CONCLUSION: Risk factor aggregation was found in all cerebral infarction patients, which is closely associated with the probability of cerebral infarction resulting from hyperbaric oxygen therapy.

OBJECTIVE:To prepare Potassium dehydroandrographolide succinate(PDS)hollow suppository and establish a method for its quality control.METHODS:The PDS hollow suppository was prepared with semisynthesis fatty acid glyceride as ground substances and PEG300 or 1,2 propylene glycol as disperse medium.The content of PDS was determined by ultraviolet spectrophotometry at a detection wavelength of 251nm.RESULTS:The linear concentration range of PDS was 6.0～50.0?g?mL-1(r=0.999 9,n=5).The two kinds of PDS hollow suppository were all up to the quality standard.CONCLUSION:This method is reasonable in design and feasible in technology.