BACKGROUND: It is indicated in latest research that in cerebral protective measures of cerebral vasospasm induced by subarachnoid hemorrhage due to various factors in acute stage, mild hypothermia has been drawn the attention specially and it has been recommended in clinical practice. But such therapy is generally limited in experimental research and aneurysm hemorrhage, the clinical research on subhypothermia probably provides important influence on cerebral vasospasm in severe craniocerebral injury.OBJECTIVE: Based on cerebral vascular hemodynamical indexes (CVDI),the cerebral protection of subhypothermia was observed on cerebral vasospasm in severe craniocerebral injury.DESIGN: Randomized controlled experiment.SETTING: Department of Neurological Surgery of No.16 Hospital of Chinese PLA and General Military Institute of Neurological Medical Science in Zhujiang Hospital Affiliated to First Military Medical University of Chinese PLA.PARTICIPANTS: Totally 36 cases of severe craniocerebral injury were selected in General Military Institute of Neurological Medical Science in Zhujiang Hospital Affiliated to First Military Medical University of Chinese PLA from July 1997 to August 1999, which were randomized into the control and treatment group, 18 cases in each one. At same period, 24 cases with normal CVDI were screened and taken as normal group. All of receptors participated in the experiment in volunteer.METHODS: In both the control and treatment group, the treatment was applied with anti-inflammation, stopping bleeding, fluid limitation, dehydration, supporting, hyperbaric oxygen, etc. In the control, the normal body temperature was maintained and in treatment group, anus temperature was dropped to about 33 ℃ in 4 hours to 8 hours, which was maintained for 3-test was given on the day of injury (0), on the 1st, 3rd, 7th, 14th and 21st days assay was done on the day of injury (0), on the 1st, 3rd, 7th, 14th and 21st days successively, in which, minimum blood velocity (Vmin) and minimum blood flow (Qmin) reflect blood supply of distal cerebral vessel and blood flow.Cerebral vessel resistance (CVR) reflects smooth degree of cerebral microcirculation. Dynamical resistance (DR) reflects auto-regulation of cerebral vessel. Criteria of evaluation: Recovery state of consciousness was justified according to Glasgow Coma Scale (GCS) in 1 week after injury. The outcomes were evaluated according to Glasgow outcome scale (GOS) in 3 months (5 score: good, 4 score: moderate handicapped, 3 score: severely handicapped, 2 score: vegetative state and 1 score: death). The case over 4 score indicated good outcome.ery of consciousness and outcomes in 1 week after injury in the control and treatment group.RESULTS: Totally 36 cases of severe craniocerebral injury entered result phases after injury in the control, named hypoperfusion phase (0 day), hyperperfusion phase (1-3 days), cerebral vasospasm phase (4-14 days) and improving phase (＞15 days). In treatment group, 3 phases were manifested,named hypoperfusion phase (0 day), improving phase (1-3 days) and recovery phase (＞ 4 days), without hyperperfusion phase. Eight cases and 2 cases of cerebral vasospasmodic changes in CVDI presented in the control in focus: The maximum volume (140.9±22.95) cm3 was on the 14th day after injury in the control and that (95.83-±14.97) cm3 was on the 3rd day in treatment group. On the 14th day after injury, the volume in treatment group in 1 week after injury: It was 22.2% (4/18) in the control and 55.6%(10/18) (P ＜ 0.05) in treatment group. Improving outcome rate: It was 38.9% (7/18) and 66.7% (12/18) in treatment group.CONCLUSION: Subhypothermia reduces incidence of cerebral vasospasm by stabilizing cerebral circulation after severe craniocerebral injury, especially by inhibiting acute hyperperfusion after the injury so that the volume of cerebral edema in focus is lessened remarkably and the prognosis is improved.

Objective To compare the differences of disease spectrum between patients with brain trauma injury (TBI) in the high altitude areas and those in the plain areas.Methods The front page information of medical records of local TBI patients admitted to military hospitals from 2001 to 2007 was extracted from the Chinese Trauma Database.Ten military hospitals from high altitude areas (high altitude group) and 10 military hospitals with the same hospital level from plain areas (plain group) were selected and the patients in the two groups were compared for their differences in general condition and disease spectrum.Results High altitude group displayed a larger proportion of male patients (P＜0.01),a lower age (P＜0.01),a smaller proportion of patients with Han nationality (P＜0.01),asmaller proportion of emergency patients (P＜0.01),a larger proportion of critically ill patients (P＜0.01),a lower median of hospital days (P＜0.01),a lower operation rate (P＜0.01),as compared with the plain group.The injury of the patients with TBI in turn were intracranial organ injury (excluding those with skull fracture),open wound of head,neck,and trunk,skull fracture,injury of nerves and spinal cord.The orders of TBI disease spectrum of the high altitude and plain groups were the same,but the disease compositions of the two groups had significant difference (P＜0.01).Conclusions Thereexist significant differences in demographics,admission status and disease spectrum of TBI patients inhigh altitude and plain areas.However,the current clinical treatments of TBI in high altitude areas are usually with reference to the experience in plain areas,which is worthy of paying attention by relevant departments.

BACKGROUND:There is a lack of the research concerning the biocompatibility of nano-hydroxyapatite/polyphenylene sulfide (nHA/PPS) composites.OBJECTIVE:To evaluate the in vivo biocompatibility of nHA/PPS composites based on the completed research in vitro.METHODS:Systemic toxicity test:Sprague-Dawley rats were given the intraperitoneal injection of nHA/PPS extract or normal saline.The general situation,body mass and the histological changes of the liver and kidney were observed at 72 hours after injection.Delayed type hypersensitivity test:nHA/PPS extract or normal saline was injected subcutaneously into the back of the rats.Afterwards,skin irritation symptoms were observed at 72 hours.Local reaction experiment:nHA/PPS composites and polyethylene were respectively implanted into the back of the rats.The pathological changes of the implanted materials and their surrounding tissues were observed at 15 and 30 days after implantation.RESULTS AND CONCLUSION:(1) The rats were in good situation after nHA/PPS injection;the body mass increased steadily,which showed no significant difference from the control group (P ＜ 0.05);the morphology and color of the liver and kidney were normal,and the systemic toxicity of the composite materials was normal according to the degree of toxicity classification.(2) There were no obvious skin irritation symptoms after the subcutaneous injection of nHA/PPS composites,and the primary irritation index was less than 0.4,suggesting a low hypersensitivity.After implantation of nHA/PPS composites,there was no obvious degradation,absorption and rejection,and both the degree of inflammatory reaction (15 days ≤ level Ⅲ,30 days ≤ level Ⅱ) and the thickness of fibrous capsule (15 days ≤ level Ⅲ,30 days ≤ level Ⅱ) revealed the good biocompatibility of the composites.These results suggest that the nHA/PPS composites hold an excellent biocompatibility in vivo.