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81.
颅内动脉瘤术后低血压反应的危险因素分析 总被引:2,自引:0,他引:2
目的总结颅内动脉瘤术后低血压的发生与预后的关系,明确术后低血压发生的危险因素。方法回顾性分析接受开颅动脉瘤手术的127例病例,使用Ridit分析研究低血压的发生与预后的相关性。以性别、年龄、术前Hunt-Hess分级、术前高血压病史、低钠血症、心电图改变、术前蛛网膜下腔出血程度、术前尼膜地平应用、手术时机的选择、术中脑室穿刺引流、术中载瘤动脉阻断时间、术中控制性降压持续时间、术中控制性降压程度、术中动脉瘤破裂与否等14个可能的危险因素为自变量,设定术后“发生低血压”为变量,使用logistic回归分析研究相关的危险因素。结果正常血压组预后优于低血压组。术前心电图改变、术前蛛网膜下腔出血程度、术中载流动脉阻断时间、术中动脉瘤破裂与否等4个因素为低血压发生的危险因素。结论动脉瘤病人术后低血压反应严重影响病人预后。针对低血压发生的危险因素的防治,有望减少和纠正低血压反应,改善预后。 相似文献
82.
目的探讨颈内动脉巨大动脉瘤的特点和手术策略。方法回顾性分析48例颈内动脉大型和巨大型动脉瘤的手术经验。手术均采用翼点人路,床突旁动脉瘤病例预先暴露颈部颈内动脉以备临时阻断。从硬脑膜内磨除前床突、视神经管上壁以及外侧嵴,以显露动脉瘤的近侧角。术中采用逆向抽吸法使动脉瘤塌陷,如动脉瘤内含机化血栓,则在临时阻断后切开瘤体,用CUSA和取瘤镊去除瘤内血栓,再将动脉瘤夹闭并达到视神经减压的目的。术中监测脑电图和体感诱发电位,并采用术中超声多普勒检查动脉血流。结果46例动脉瘤直接夹闭,2例海绵窦段动脉瘤行动脉瘤孤立并分别做颞浅动脉-大脑中动脉和大隐静脉移植颈外动脉-大脑中动脉搭桥手术。43例术后行DSA检查,绝大多数动脉瘤夹闭满意。按GOS评分术后良好为41例(85.4%),差为5例,死亡2例。结论充分显露、合理应用临时阻断技术、有效的动脉瘤减压,以及术中应用电生理监测和超声多普勒检查等辅助措施,能够取得动脉瘤的满意夹闭。 相似文献
83.
Carotid baroreflex function ceases
during vasovagal syncope 总被引:2,自引:0,他引:2
Shigehiko Ogoh PhD Stefanos Volianitis PhD Peter B. Raven PhD Niels H. Secher MD 《Clinical autonomic research》2004,14(1):30-33
Abstract. Despite the arterial baroreflex control of heart rate and
blood pressure, vasovagal syncope is a common cause of loss of
consciousness in people exposed to stimuli that reduce the
central blood volume, such as head-up tilt. Carotid baroreflex
function was evaluated using a rapid pulse train of neck
pressure and neck suction in three conscious volunteers who
developed a vasovagal episode during head-up tilt. The maximal
gain of the carotid-heart rate and carotid-blood pressure
baroreflex function curves were identified as measures of
carotid baroreceptor responsiveness. When presyncopal symptoms
developed, one further baroreflex assessment was obtained before
the subjects were returned to the supine position. The
bradycardia and hypotension exhibited during pre-syncope and
syncope reflected a leftward and downward relocation of both the
cardiac and vasomotor stimulusresponse curves. In addition,
during the vasovagal syncope, baroreflex control was suppressed
as blood pressure remained low during neck pressure stimuli. In
conclusion, arterial baroreflex function ceases during vasovagal
syncope. 相似文献
84.
ATP和SNP控制性降压对血流动力学的影响 总被引:1,自引:1,他引:0
对比研究三磷酸腺苷(ATP)和硝普钠(SNP)控制性降压对氯胺酮麻醉犬血流动力学的影响。选择犬14只,随机分为ATP组和SNP组,由股静脉持续输入ATP和SNP使MAP降低30% ̄40%,维持30min,分别于降压前、降压后15min、30min及停止降压后15min用Swan-Ganz漂浮导管测定血流动力学指标。结果表明,ATP、SNP降压期间SVR、LVSW显著降低,CO、PCWP、SV、RV 相似文献
85.
Rolf Inderbitzi Markus Furrer Christian Klaiber Hans Beat Ris Heinz Striffeler Ulrich Althaus 《Surgical endoscopy》1992,6(4):189-192
Summary Thoracoscopic surgery is decidedly expanded by the ability to perform pulmonary wedge resections of the lung by using the Endo-GIA-stapler. In addition to thoracoscopic biopsies, since July 1991 we have carried out wedge resections in 12 patients suffering from spontaneous pneumothorax (nine) or peripheral bronchial carcinoma (three). Postoperatively one air fistula persisted over 9 days. The chest tube was removed within 48 h in all other patients. There was no other major complication. The postoperative hospitalization period lasted 4.6 days (1–9 days). Operating time was 44 min (30–70 min). The benefit for the patient consists in the little-impaired breathing mechanics, the short hospital stay, and the favorable cosmetic result. 相似文献
86.
Yoshihiko Tsuji Hiroaki Ohue Hiroshi Ikuta Osamu Kinoshita Fumio Shibagaki 《Surgery today》1997,27(5):387-391
Between January 1985 and September 1994, 21 patients with psychiatric disorders underwent various forms of surgery at our
hospital. There were 12 men and 9 women with an average age of 57.6 years. The coexisting psychiatric disorders were schizophrenia
in 15 patients, depression in 2, dementia in 2, mental retardation with epilepsy in 1, and Parkinson's disease in 1. All the
patients had been receiving neuroleptic medications for a long period. The indications for surgery were: cholelithiasis in
6 patients, acute appendicitis in 4, perforation of the small intestine in 3, incarceration of an inguinal hernia in 2, and
esophageal cancer, stomach cancer, bleeding from a gastric ulcer, perforation of a duodenal ulcer, strangulating ileus, and
burns in 1 patient each, respectively. All of the patients who underwent elective surgery were given epidural anesthesia with
or without general anesthesia. Antipsychotic medications were given until just prior to surgery and recommenced concurrent
with the first meal. Abnormal behavior was observed in 11 patients (52.4%) postoperatively, but all the patients were discharged
in accordance with recovery from their surgical disorder. Intra- and postoperative hypotension resistant to intravenous catecholamine
administration was recognized in 9 patients (42.9%), and this peculiar complication should be borne in mind when patients
with psychiatric disorders require surgical management.
Presented at the 94th annual meeting of the Japanese Surgical Society, held in Tokyo in March, 1994 相似文献
87.
Continuous recording of middle cerebral artery blood velocity in clinical neurosurgery 总被引:5,自引:0,他引:5
Summary Intracranial pressure, arterial blood pressure, and middle cerebral artery blood velocity were monitored for periods from 1 to 10 days in 30 neurosurgical intensive care patients. The recordings revealed rapid changes in the cerebral perfusion and gave insight into individual cerebral haemodynamic states.Twenty patients consistently showed CO2 reactivity within normal limits, between 2.5 and 5% per mm Hg (19–38% per kPa). Severely impaired CO2 reactivity, considerably below 1% per mm Hg (7.5% per kPa) was observed in four patients. Three of these patients died, while the fourth patient survived in a persistent vegetative state.Seven patients demonstrated pressure-passive blood velocity changes throughout the observed CPP range. The four patients with severely impaired CO2 reactivity all belonged to this group. The recordings from three of the remaining 23 patients showed signs of MCA blood velocity autoregulation with a lower regulatory limit of about 40–45 mm Hg. This observation is in keeping with findings from electromagnetic flowmetry on brain arteries in the neurosurgical operating field, and supports blood velocity measurements as a relevant index of brain perfusion in clinical neurosurgery and neuro-intensive care settings. 相似文献
88.
目的 观察控制性降压结合急性高容血液稀释 (AHH)对脑膜瘤手术的安全性及减少出血量和术后血红蛋白 (Hb)、红细胞比积 (Hct)的影响。 方法 择期脑膜瘤手术病人 2 0例 ,随机分成控制性降压结合AHH组 (Ⅰ组 ,n =10 )和对照组 (Ⅱ组 ,n =10 ) ,两组均采用气管内全麻。Ⅰ组病人于气管插管后手术开始前完成AHH并进行控制性降压。比较两组病人术中出血量、输血量和术后Hb、Hct变化。 结果 Ⅰ组病人术中平均出血量 (5 44± 92 )ml ,比Ⅱ组病人的 (10 72± 182 )ml减少 49 7% ;Ⅱ组病人平均输血量 (62 0± 112 )ml ,Ⅰ组病人则完全避免输异体血。两组病人术毕均有轻度贫血 ,但仍在安全水平范围内。 结论 控制性降压结合急性高容血液稀释可安全应用于脑膜瘤手术 ,对有指征病人的使用可避免术中输异体血 相似文献
89.
Vasomotion in rat diaphragm microcirculation at rest and during stepwise arterial pressure reduction
C. W. CHEN C. H. LEE T. R. HSIUE H. Y. CHANG 《Acta physiologica (Oxford, England)》1997,161(3):281-288
The effect of haemorrhagic hypotension on the incidence, frequency and relative amplitude of vasomotion in rat diaphragm microcirculation was assessed by laser Doppler flowmetry (LDF). Graded bleeding to four hypotension levels (80, 60, 40 and 30% of the control state) were performed in 24 Sprague–Dawley rats. The incidence of vasomotion was 83% in the control state, 96% at the 80% level, 100% at the 60% level, 96% at the 40% level, and 46% at the 30% level. The median fundamental frequency of vasomotion determined manually during the control state and at the hypotension levels (in descending order) was 4.11 (range, 3.29–5.58) cycles min?1 (cpm), 4.48 (3.21–5.92) cpm, 4.20 (3.5–5.56) cpm, 4.01 (3.33–5.36) cpm, 3.71 (3.25–4.49) cpm (P < 0.01 from the fundamental frequency at 80 and 60% hypotension levels). The median relative amplitudes determined manually during the control state and descending hypotension levels were 44.5% (range, 24.9–135.9%), 69.4% (26.6–147.2%), 84.0% (40.3–177.1%) (P < 0.01 from resting and last stage of bleeding), 90.40% (26.2–189.6%) (P < 0.01 from resting and last stage of bleeding), 69.2% (35.6–93.2%). We concluded first that during the resting condition, vasomotion was frequently present in diaphragm microcirculation, which is distinct from other vascular beds of skeletal muscles. Second, the relative amplitude of vasomotion during haemorrhagic hypotension plotted against decreasing blood pressure exhibited a reverse U-shaped curve with a maximum at 40–60% of the control blood pressure, while the frequency of vasomotion remained relatively constant until the last stage of haemorrhage and centred around 3–5 cpm. 相似文献
90.
经颅多普勒频谱参数与急性颅脑损伤患者颅内压的关系 总被引:2,自引:2,他引:0
目的探讨急性颅脑损伤患者的经颅多普勒频谱参数与颅内压的关系。方法应用TCD检测20例急性中、重型颅脑损伤患者双侧大脑中动脉,同时行颅内压监测。结果经颅多普勒频谱参数cf、PI、af、RI、ae均和ICP正相关,Vd、ac和ICP负相关,其中cf与ICP的相关系数最大。建立TCD相关参数与ICP的多元线性回归方程:ICP=0.312MAP-1.531Vd+21.437PI-15.059ac+38.722cf(P<0.001,R2=0.920估计值的标准差=4.0972mmHg)。结论经颅多谱勒频谱参数可以反应颅脑损伤患者的颅内压的改变。综合研究经颅多谱勒频谱参数、血压与颅内压的关系是应用经颅多普勒无创监测颅内压的方向。 相似文献