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991.
Postischemic spontaneous hyperthermia and its effects in middle cerebral artery occlusion in the rat 总被引:17,自引:0,他引:17
Reglodi D Somogyvari-Vigh A Maderdrut JL Vigh S Arimura A 《Experimental neurology》2000,163(2):399-407
This study examined the time course and effects of postischemic spontaneous hyperthermia after transient and permanent focal ischemia. Rats underwent a 90-min, 120-min, or permanent middle cerebral artery occlusion (MCAO). Body temperatures started rising 15-20 min after MCAO and reached 39-40.5 degrees C during the first hour. Sustained hyperthermia was observed during the rest of the first 24 h. In another experiment, rats were subjected to the same interventions, but a normothermic body temperature was maintained. Spontaneous hyperthermia significantly increased the infarct volumes measured 48 h after MCAO in all groups. Reperfusion 2 h after the onset of ischemia was not beneficial in the hyperthermic animals in contrast to the normothermic group. We also examined the effect of spontaneous hyperthermia on the temporal progression of infarcted and penumbral areas 4, 12, or 48 h after MCAO. During spontaneous hyperthermia, penumbral areas became infarcted areas more rapidly, which was most expressed at 4 h. These findings demonstrate that severe spontaneous hyperthermia can occur in rats after MCAO and that it not only increases the infarct volumes in both transient and permanent ischemia, but also accelerates the incorporation of penumbral areas into necrotic areas, which significantly decreases the window of opportunity for therapeutic interventions. 相似文献
992.
Tenling A Joachimsson P-O Tydén H Hedenstierna G 《Acta anaesthesiologica Scandinavica》2000,44(9):1071-1076
BACKGROUND: A lasting impairment of pulmonary function is common after cardiac surgery. Pain from the sternotomy may contribute to the impairment. Thoracic epidural analgesia (TEA) can efficiently relieve pain in the postoperative phase, but may also affect respiratory muscle function if local anaesthetics are used. We examined the effects of TEA on pulmonary function and ventilation at rest, before and after coronary artery bypass graft surgery (CABG). METHODS: Thirty patients scheduled for CABG were randomized to receive either general anaesthesia alone or general anaesthesia with TEA. Before and after the operation the patients were examined by respiratory inductive plethysmography and spirometric tests. RESULTS: Before the operation, TEA caused significant reductions in forced vital capacity (FVC), forced expired volume in 1 s (FEV1), maximal inspiratory (PImax) and expiratory (PEmax) pressure. The rib cage contribution to tidal volume decreased significantly but the co-ordination of the thoracic and abdominal movements remained essentially unaffected. Minute volume and respiratory frequency did not change significantly. On the first postoperative day a decrease in maximal breathing efforts was found in both groups. No differences between the groups in FVC, FEV1 and PImax were found, but PEmax was significantly greater in the TEA group. Despite the impairment, breathing at rest was largely normal in both groups. CONCLUSIONS: A better pain-relief from TEA after CABG may improve the ability to cough by a greater expiratory muscle strength. FVC, FEV1, PImax and breathing at rest are not affected by TEA after cardiac surgery. 相似文献
993.
BACKGROUND: Coronary artery bypass graft (CABG) surgery with the use of mammary arteries is associated with severe alteration of lung function parameters. The purpose of the present study was to compare the effect on lung function tests of conventional physiotherapy using incentive spirometry (IS) with non-invasive ventilation on continuous positive airway pressure (CPAP) and with non-invasive ventilation on bilevel positive airway pressure (BiPAP or NIV-2P), METHODS: Ninety-six patients were randomly assigned to 1 of 3 groups: NIV-2P (1 h/3 h), CPAP (1 h/3 h) and IS (20/2 h). Pulmonary function tests and arterial blood gases analyses were obtained before surgery. On the 1st and 2nd postoperative days, these parameters were collected together with cardiac output and calculation of venous admixture. RESULTS: For the 3 groups a severe restrictive pulmonary defect was observed during the 1st postoperative day. On the 2nd postoperative day, in opposition to IS, intensive use of CPAP and NIV-2P reduced significantly the venous admixture (P<0.001) and improved VC, FEV1 and PaO2 (P<0.01). CONCLUSION: We conclude that preventive use of NIV can be considered as an effective means to decrease the negative effect of coronary surgery on pulmonary function. 相似文献
994.
Berkman MZ Iplikçioğlu AC Berkman MK Erbengi T San T Sav A 《Acta neurochirurgica》2000,142(9):1047-1054
Summary ? Background. Cerebral vasospasm after subarachnoid hemorrhage (SAH) has remained a major cause of morbidity and mortality in patients
with SAH. Excitatory neurotransmitters are gathered in the extracellular space during ischemia due to cerebral vasospasm and
initiate or stimulate a series of pathophysiological biochemical processes which consequently lead to neuronal death. Tizanidine
(Sandoz compound DS 103–282, 5-chloro-4,2 (2-imidazolin-2-yl-amino)-2,1,3-benzothiazol hydrochloride) is a centrally-acting
muscle relaxant and a selective α 2 adrenoreceptor agonist which shows its effect by stimulating presynaptic α 2 adrenoreceptors
in central ASPergic and GLUergic system by inhibiting aspartic acid and glutamic acid release. In this study, the effect of
Tizanidine on vasospasm was evaluated.
Methods. We used a femoral artery vasospasm model in rats which has been described by Okada et al. 60 rats were examined in three groups. The first group was used as control group (Control) (n=20), in the second group subarachnoid
hemorrhage was performed (SAH) (n=20), in the third group Tizanidine was administered in addition to SAH (SAH+Tizanidine administration)
(n=20). Animals in SAH+Tizanidine administration group received 0,3 mg/kg/day intraperitoneally for 7 days. Seven days after
the experiment, after perfusion-fixation, 10 mm segments of both femoral arteries were removed and the femoral artery was
prepared for light microscope examination, scanning and transmission electron microscopy and for morphometric analysis.
Results. There was a statistically significant difference between the electron, scanning and light microscopic observations and morphometric
analysis of SAH+Tizanidine administration group and SAH group, and no statistically significant difference between SAH+Tizanidine
administration group and control group.
Conclusion. This study has disclosed that Tizanidine administration before the vasospasm reduces ultrastructural and morphometric vasospastic
insult significantly. However, the clinical application of Tizanidine as a protective and therapeutic agent in cerebral vasospasm
needs further studies including the employment of clinically more relevant SAH models. 相似文献
995.
Sandström K Wallerstedt SM Tornebrandt K Bodelsson M 《Acta anaesthesiologica Scandinavica》2000,44(8):1011-1016
BACKGROUND: The intravenous anaesthetic propofol inhibits the neuronal uptake of noradrenaline (uptake1) from the vascular sympathetic neuromuscular junction, resulting in an enhancement of the sympathetic neurotransmission. This could be important for maintenance of blood pressure during propofol anaesthesia. The aim of the present study was to determine how propofol influences the kinetics of uptake1. METHODS: Isolated segments of rat femoral arteries were incubated with [3H]-noradrenaline in the presence or absence of propofol and the radioactivity taken up was measured in a scintillation counter. The uptake1 inhibitor, desipramine, was used to delineate the specific neuronal uptake. RESULTS: Desipramine and 10 microM propofol significantly reduced the uptake in segments incubated with 0.1 microM [3H]-noradrenaline. Propofol at 1 microM and 100 microM did not affect the uptake. Non-linear regression analysis of specific uptake yielded Km 0.50 microM, Vmax 1.6 pmol mg(-1) 15 min(-1) and Hill coefficient 1.1. Propofol (1-10 microM) increased the Km value and propofol (10-100 microM) increased the Vmax value concentration-dependently, while the Hill coefficient was not affected. CONCLUSION: Propofol seems to have a biphasic effect on the uptake of noradrenaline in the vascular sympathetic neuromuscular junction. At lower propofol concentrations there is a decrease in the affinity of the noradrenaline transporters. The resulting uptake inhibition is counteracted at higher propofol concentrations by an increase in the efficacy of the uptake. 相似文献
996.
Kieler-Jensen N Jolin-Mellgård A Nordlander M Ricksten SE 《Acta anaesthesiologica Scandinavica》2000,44(2):186-193
BACKGROUND: The aim was to evaluate the use of clevidipine, a new vascular selective, ultra-short-acting calcium antagonist for blood pressure control after coronary artery bypass grafting (CABG). METHODS: The effects of clevidipine on central hemodynamics, myocardial blood flow and metabolism were studied at two different phases after CABG. In phase 1 (n=13), the hypertensive phase, the effects of clevidipine were compared to those of sodium nitroprusside (SNP) when used to control postoperative hypertension. In phase 2 (n=9), the normotensive phase, a clevidipine dose-response relationship was established. RESULTS: At a target mean arterial pressure (MAP) of 75 mmHg, systemic vascular resistance (SVR) and heart rate (HR) were lower, preload, stroke volume (SV) and pulmonary vascular resistance (PVR) were higher, while there were no differences in myocardial lactate metabolism or oxygen extraction with clevidipine compared to SNP. In the normotensive phase, clevidipine induced a dose-dependent decrease in MAP (-19%), SVR (-27%) and PVR (-15%), accompanied by an increase in SV (10%), but no reflex increase in HR or changes in cardiac preload. Clevidipine caused a direct coronary vasodilation, as indicated by a decrease in myocardial oxygen extraction from 54% to 45%. Myocardial lactate metabolism was unaffected by clevidipine. The blood clearance of clevidipine was 0.05 l x min(-1) x kg(-1), the volume of distribution at steady state was 0.08 l x kg(-1) and the initial and terminal half-lives were <1 min and 4 min, respectively. CONCLUSIONS: Clevidipine rapidly reduced MAP and induced a systemic, pulmonary and coronary vasodilation with no effect on venous capacitance vessels or HR. Clevidipine caused no adverse effects on myocardial lactate metabolism. Clevidipine thus appears suitable to control blood pressure after CABG. 相似文献
997.
Statistical Analysis of Factors Affecting the Outcome of Patients with Ruptured Distal Anterior Cerebral Artery Aneurysms 总被引:3,自引:0,他引:3
Miyazawa N Nukui H Yagi S Yamagata Z Horikoshi T Yagishita T Sugita M 《Acta neurochirurgica》2000,142(11):1241-1246
Summary
The clinical factors affecting the outcome of patients with ruptured distal anterior cerebral artery (ACA) aneurysms were
analyzed using multiple logistic regression analysis.
The medical records were reviewed of 52 patients (57 aneurysms) with ruptured distal ACA aneurysms operated on by the same
neurosurgeon over 25 years. The standard policy was early surgery for patients in Hunt and Kosnik grades I to IV. Age, sex,
Hunt and Kosnik grade, timing of operation, size of aneurysms, number of aneurysms, association of intracerebral haemorrhage
(ICH), intraventricular haemorrhage, and azygos ACA, use of temporary clipping , occurrence of premature rupture, and presence
of psychiatric change were investigated. Univariant analysis disclosed that clinical grade (P=0.0006), size of aneurysm (P=0.005),
and size of ICH (P=0.012) affected the outcome of patients. Multiple logistic regression analysis found that Hunt and Kosnik
grade (P=0.010) and timing of operation (P=0.033) affected the outcome. There was no significant relationship between long-term
outcome and clinical factors, although a close relationship was found with Hunt and Kosnik grade (P=0.071).
Clinical grade and timing of the operation affected the outcome of patients with ruptured distal ACA aneurysms. Patients
harboring ICH of over 3 cm diameter in poor grades should also be carefully treated. 相似文献
998.
针对湖南省华容县灾害性移民的医疗问题,提出建立医疗救助和新型农村合作医疗两个层次的移民医疗保障体系,并分析新型农村合作医疗在移民地区的适用性。 相似文献
999.
目的 探讨适度告知对冠状动脉病变严重狭窄病人的心肌缺血事件的影响。 方法 将实施冠状动脉造影后示多支多处严重狭窄需进d一步治疗的 10 5例病人随机分为观察组 (5 3例 )和对照组 (5 2例 ) ,观察组只告知冠脉有病变 ,不告知具体病变血管支数和狭窄程度 ,对照组被告知冠状动脉造影真实结果 ,两组均将造影所示结果告知病人家属。观察并比较两组病人造影术后 4h焦虑值及 3d内心肌缺血发生情况。 结果 观察组焦虑值及心肌缺血事件发生率均低于对照组 (P <0 .0 1)。 结论 冠状动脉病变适度告知可减少多支多处严重狭窄病人冠状动脉造影后心肌缺血事件发生率 相似文献
1000.
颈椎前路内固定钢板系统的结构分析与应用 总被引:1,自引:0,他引:1
分析了几种颈椎前路内固定钢板系统在结构设计上的特点,以期对颈椎前路内固定钢板系统的临床应用以及研制和设计适合国人的颈椎前路内固定钢板系统提供参考. 相似文献