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101.
Noninvasive Intracranial Cerebral Flow Velocity Evaluation in the Emergency Department by Emergency Physicians 总被引:2,自引:0,他引:2
Michael Shafé MD Michael Blaivas MD RDMS Edmond Hooker MD Leigh Straus BS 《Academic emergency medicine》2004,11(7):774-777
Transcranial Doppler (TCD) is an accepted modality for the evaluation of cerebral blood flow velocities. OBJECTIVES: The purpose of this study was to test the feasibility of bedside TCD measurement in the emergency department (ED) with critically ill, intubated patients. METHODS: A prospective convenience sample of patients presenting to a university hospital over a two-month period underwent TCD evaluation of the middle cerebral artery. Intubated patients with head trauma and any patient requiring tracheal intubation were eligible. A 2-MHz Doppler probe was positioned over the temporal bone to acquire blood flow velocities. An emergency medicine resident and research assistant obtained measurements. Continuous TCD tracings were recorded on a video cassette recorder tape for quality assurance review and data collection. Vital signs and therapeutic interventions were also recorded. Flow velocities were measured in cm/s; the peak Resistance Index (RI) was calculated for each patient. RESULTS: A total of 30 patients were enrolled in the study. Adequate tracings were obtained in 25 patients (83%) without a disruption of resuscitation. Tracings could not be obtained in five patients; they were listed as TCD failures. However, in two of these patients, adequate flow velocity tracings were obtained after resuscitation. Four patients were evaluated during tracheal intubation. One patient was monitored successfully during cardiopulmonary resuscitation. The median time required for data acquisition was 1.9 minutes. The mean highest RI for those who expired was 0.84. For those who survived, the mean highest RI was 0.52. The difference of 0.32 was statistically significant (p = 0.04). CONCLUSIONS: Noninvasive blood flow velocity monitoring of the middle cerebral artery using TCD is feasible in the ED when performed at the bedside on intubated patients with traumatic brain injury and others during tracheal intubation and resuscitation. 相似文献
102.
Dan Greitz 《Child's nervous system》2007,23(5):487-489
Objective This study aims to question the generally accepted cerebrospinal fluid (CSF) bulk flow theory suggesting that the CSF is exclusively
absorbed by the arachnoid villi and that the cause of hydrocephalus is a CSF absorption deficit. In addition, this study aims
to briefly describe the new hydrodynamic concept of hydrocephalus and the rationale for endoscopic third ventriculostomy (ETV)
in communicating hydrocephalus.
Critique The bulk flow theory has proven incapable of explaining the pivotal mechanisms behind communicating hydrocephalus. Thus, the
theory is unable to explain why the ventricles enlarge, why the CSF pressure remains normal and why some patients improve
after ETV.
Hydrodynamic concept of hydrocephalus Communicating hydrocephalus is caused by decreased intracranial compliance increasing the systolic pressure transmission into
the brain parenchyma. The increased systolic pressure in the brain distends the brain towards the skull and simultaneously
compresses the periventricular region of the brain against the ventricles. The final result is the predominant enlargement
of the ventricles and narrowing of the subarachnoid space. The ETV reduces the increased systolic pressure in the brain simply
by venting ventricular CSF through the stoma. The patent aqueduct in communicating hydrocephalus is too narrow to vent the
CSF sufficiently. 相似文献
103.
BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them.
OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia.
DESIGN: A randomized controlled trial.
SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University.
MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5–5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden).
METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3–]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3– and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33–35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling.
MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group.
RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P < 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P < 0.05], and brain tissue pH value was higher [(7.03±1.63), (9.40±1.30) kPa, P < 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P < 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P > 0.05)
CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis. 相似文献
104.
眼底动脉硬化与血压、血糖、血脂的多元分析与评估 总被引:1,自引:0,他引:1
目的探讨眼底动脉硬化与血压、血脂、血糖的相关性,评估中风危险度。方法对2004年5月至2008年10月就诊的患者335例,作为观察组,并与无症状的健康体检者180例作对照,动态检测眼底动脉硬化、血压、血糖、血脂的异常变化,并做综合量化评估。结果脑血管疾病与眼底动脉硬化、血压、血糖、血脂等因素密切相关。结论眼底动脉硬化、血糖、血脂、血压异常的量化评分,能够预估中风,以便采取预防性治疗。 相似文献
105.
目的:观察正压压膜式间隙保持器的临床应用特点和效果.方法:选择60例5.9~10岁的乳牙过早缺失的患儿,随机分为实验组和对照组,实验组用正压压膜式间隙保持器,对照组用带环式丝圈间隙保持器.分别从患者对保持器的接受程度、保持器的制作、椅旁操作时间、固位效果及其保持疗效和因保持器本身问题导致的复诊率进行对比研究,并对测量数据进行统计学处理.结果:两组患者在对保持器的接受程度、保持器的制作、椅旁操作时间、美观、防止对合牙过度伸长方面具有显著的差异,在固位效果及其保持疗效和因保持器本身问题的复诊率上有差异,但是差异没有显著性.结论:正压压膜式间隙保持器是一种美观舒适,制作简单,戴用便捷、固位好,疗效佳,便于观察恒牙萌出程度的间隙保持器,它为口腔医师进行保持缺隙治疗时提供了一种新的选择. 相似文献
106.
早期脑室置管行颅内压监护对中型颅脑损伤患者的预后影响 总被引:1,自引:0,他引:1
目的 探讨早期脑室置管行颅内压 (ICP)和脑灌注压 (CPP)监护在中型颅脑损伤中的临床应用价值。方法 将 12 5例伤后 2 4h入院无手术指征的中型颅脑损伤 (GCS 9~ 12分 )患者 ,随机分为ICP监护组 :入院后即经恻脑室内穿刺置管行ICP与CPP连续监测 ,根据颅内压变化调整治疗方案 ;对照组 :入院后不做ICP监测 ,依据临床观察的意识及生命体征变化 ,进行治疗。结果 颅内压监护组脱水剂剂量、应用时间均低于对照组 ,疗效优于对照组 ,两组差异有显著意义 (P <0 0 5 )。结论 中型颅脑损伤病情极不稳定 ,早期行ICP监护能及早发现病情变化 ,对及时采取有效治疗措施 ,降低死残率 ,改善预后有重要意义。 相似文献
107.
H. S. Pollinger M. D. Stegall J. M. Gloor S. B. Moore S. R. Degoey N. A. Ploeger W. D. Park H. S. Pollinger M. D. Stegall J. M. Gloor S. B. Moore S. R. Degoey N. A. Ploeger W. D. Park 《American journal of transplantation》2007,7(4):857-863
The immunologic risk associated with donor-specific antibodies (DSA) against Class II human leukocyte antigens (HLA) in kidney transplant (KTx) recipients is unclear. The aim of this study was to determine the outcome of KTx when DSA was detected only against HLA Class II. To isolate the impact of anti-Class II DSA, we retrospectively analyzed 12 KTx recipients who at baseline had a positive B-cell flow cytometric crossmatch (FXM) and a negative T-cell FXM. Using alloantibody specification analysis, 58.3% (7/12) had DSA against donor Class II and 41.7% had no demonstrable DSA. Biopsy-proven AMR occurred in 57% (4/7) in the Class II(+) group and 0% in the Class II(-) group (p > 0.05). Peritubular capillaries stained positive for C4d in 86% (6/7) of the Class II(+) patients and in 40% (2/5) of the Class II(-) patients (p > 0.05). One patient in the Class II(+) group lost their graft at 3 months to accelerated transplant glomerulopathy, while all other grafts were functioning 3-37 months posttransplant despite the persistence of anti-Class II DSA. We conclude that KTx recipients with clearly defined anti-Class II DSA are at risk for humoral rejection suggesting that desensitization and/or close posttransplant monitoring may be needed to prevent AMR. 相似文献
108.
中、老年代谢综合征患者的临床特点分析 总被引:1,自引:0,他引:1
目的 比较中、老年代谢综合征(MS)患者的临床特点.方法 收集1996~2006年在解放军总医院门诊查体且符合中国人MS诊断标准(CDS)的947例中、老年患者的临床资料.其中老年人679例,中年人268例.分析中、老年患者MS各组分的差异,以及各组分的相关因素等.结果 947例患者中,男性582例(老年423例,中年159例),女性365例(老年256例,中年109例).老年男性患者的年龄大于老年女性(81.5±6.5 vs 74.5±8.8岁,P<0.01),老年男性的体重指数(BMI)高于中年男性(27.14±2.51 vs 25.98±2.38,P<0.01).老年患者的空腹、餐后血糖和收缩压均高于同性别的中年患者,而舒张压无显著差异.中年男性的甘油三酯高于老年男性.中年女性的高密度脂蛋白胆固醇高于男性.多元回归分析显示,男女患者空腹血糖均与餐后2h血糖有相关性(男性R2=0.463,P<0.05;女性R2=0.613,P<0.05).餐后2h血糖与年龄存在相关性(男性,R2=0.522,P<0.01;女性R2=0.716,P<0.05).收缩压与多种指标均有相关性,男性患者收缩压与年龄(R2=0.396,P<0.01)和舒张压(R2=0.535,P<0.05)均有相关性;女性患者的收缩压与BMI(R2=0.557,P<0.05)、舒张压(R2=0.434,P<0.05)、餐后2h血糖(R2=0.434,P<0.01)及空腹血糖(R2=0.473,P<0.05)均有相关性.Logistic回归分析示年龄(OR=2.1,95%CI:1.3~2.7)、空腹血糖(OR=1.7,95%CI:1.2~3.1)和收缩压(OR=1.4,95%CI:1.2~2.9)是预测代谢综合征组分含量的影响因素.结论 中老年代谢综合征患者的代谢指标有差异,年龄、空腹血糖和收缩压可作为代谢综合征的筛选指标. 相似文献
109.
厄贝沙坦治疗高血压患者的临床效果观察 总被引:1,自引:0,他引:1
目的:观察厄贝沙坦治疗高血压患者的临床效果。方法:选择2007年1月~2009年1月来本院就诊的高血压患者200例,随机分为两组,厄贝沙坦组100例,采用厄贝沙坦治疗4周;对照组100例采用依那普利治疗,观察患者用药前后动态血压、心脏功能变化,并评价临床疗效。结果:厄贝沙坦组患者治疗总有效率为97%,均未出现明显不良反应:与对照组比较.差异有统计学意义,P〈0.05。厄贝沙坦组治疗后24h、白昼和夜间平均收缩压和舒张压与治疗前比较,差异有统计学意义,P〈0.05;用药后血压晨峰也显著降低,与治疗前比较,差异有统计学意义,P〈0.05:但与对照组间比较,差异无统计学意义,P〉0.05。结论:厄贝沙坦治疗高血压疗效满意,安全性较高,还可降低患者的心脑血管意外的风险。 相似文献
110.
Thomas Höge 《Stress and health》2009,25(1):41-51
Against the theoretical background of the effort–recovery model and the action regulation theory, the author presents a cross‐sectional questionnaire study testing hypotheses about the relationship between work‐related time pressure, cognitive and emotional irritation, work–family conflict and psychosomatic complaints. Subjects were 576 female home care nurses. Results of a path analysis show that the relation of time pressure and psychosomatic complaints is partially mediated by experiencing a work–family conflict; also the relation of time pressure and work–family conflict is partially mediated by cognitive and emotional irritation. It is argued that cognitive and emotional irritation are fruitful concepts for a more comprehensive understanding of the relationship between work stressors and the development of strain‐based work–family conflict. Implications for the prevention of work–family conflict are outlined. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献