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21.
Biliary diseases known since ages constitute major portion of digestive tract disorders world over. Among these cholelithiasis being the fore runner causing general ill health, thereby requiring surgical intervention for total cure. The study was undertaken in an attempt to compare the hemodynamic changes in patient undergoing laparoscopic cholecystectomy using different intra-abdominal pressures created due to carbon dioxide insufflation. The patients were randomly allocated to one of the three groups in which different levels of intra-abdominal pressures (8–10 mmHg,11–13 mmHg and 14 mmHg and above) were maintained. The base line parameters monitored were heart rate, non invasive blood pressur(systolic and mean)and end tidal carbon dioxide. All the parameters were monitored at various intervals i.e. Immediately during insufflation, 5 min, 10 min, 20 min, 30 min after CO2 insufflation and after every 10 min if surgery exceeds 30 min, at exsufflation,10 min after CO2 exsufflation. Patients were ventilated with Pedius Drager Ventilator keeping tidal volume 8–10 ml/kg and respiratory rate 12–14 breaths/min. During surgery patients were placed in reverse Trendlenburg position (head up) at 15 °. The results obtained were evaluated statistically and analyzed. Baseline characteristics were found to be comparable. Hemodynamic variables were reported as mean and standard deviation. Statistical significance among groups was evaluated using Analysis of Variance and unpaired student t test (two tailed). Inter-group comparisons were made using Bonferroni test. A p-value of <0.05 was considered as statistically significant. In all the three groups the mean heart rate (baseline 84.08 ± 12.50, 87.96 ± 15.73 and 86.92 ± 17.00 respectively) increased during CO2 insufflation and the rise in heart rate continued till exsufflation after which it decreased and at 10 min after exsufflation the heart rates were comparable with the baseline. The inter-group comparison of mean heart rate between I & III was statistically significant at 10, 20, 30 min after CO2 insufflation which continued at exsufflation and 10 min after CO2 exsufflation [p < 0.05]. The inter-group comparison between I & III showed statistically significant difference in systolic blood pressure at 10, 20, 30 min after CO2 insufflation, at exsufflation and 10 min after exsufflation [p = 0.0001] and mean arterial pressure at 5, 10, 20, 30 min after CO2 insufflation, at exsufflation and 10 min after exsufflation [p = 0.0001]. Comparison between Group I and Group III & between Group II and Group III showed highly significant statistical difference in EtCO2 immediately after insufflation and the same trend was seen till the completion of surgery and even 10 min after exsufflation [p = 0.001]. The conclusion drawn from the study was that laparoscopic cholecystectomy induces significant hemodynamic changes intraoperatively, the majority of pathophysiological changes are related to cardiovascular system and are caused by CO2 insufflation .A high intra-abdominal pressure due to CO2 insufflation is associated with more fluctuations in hemodynamic parameters and increased peritoneal absorption of CO2 as compared to low intraabdominal pressure so low pressure pneumoperitoneum is feasible for laparoscopic cholecystectomy and minimizes the adverse hemodynamic effects of CO2 insufflation.

Electronic supplementary material

The online version of this article (doi:10.1007/s12262-012-0484-x) contains supplementary material, which is available to authorized users.  相似文献   
22.
BackgroundCerebellar arteriovenous malformations (cAVMs) are rare and challenging lesions with an aggressive natural history. The mechanisms whereby a patient can worsen clinically after a supratentorial AVM resection include an acute alteration in cerebral hemodynamics, which is a known cause of postoperative hyperemia, edema and/or hemorrhage. These phenomena has not been described for cAVMS. Moreover, the underlying pathophysiology of edema and hemorrhage after AVM resection still remains controversial.MethodsWe report a patient that presented an abrupt neurological deterioration after cAVM surgical resection. Emergent external ventricular drainage to treat incipient hydrocephalus only partially reverted the patient's deterioration. Consecutive post-surgery CT images revealed fourth ventricle compression secondary to cerebellar swelling that concurred with a new neurological deterioration. Densitometric analysis was performed in these CT images to reveal the nature of these changes as well as their evolution over time.ResultsImportantly, we demonstrated a dynamic increase in the cerebellum mean density at the interval of Hounsfield values which correspond to hyperemia values. These changes were dynamic, and when hyperemia resolved and cerebellar density returned to basal levels, the fourth ventricle re-expanded and the patient neurologically recovered.ConclusionsThis study demonstrated the utility of quantitative CT image analysis in the context of hemodynamic alterations following cAVM resection. Densitometric CT analysis demonstrated that hyperemic changes, but not ischemic ones, were time-dependent and were responsible for swelling and hemorrhage that conditioned neurological status and patient's evolution.  相似文献   
23.
11只健康杂种犬(雌雄不分),体重8 ̄11kg,随机分为二组:A(实验)组6只,术后胸膜腔注入丁哌卡因2.5mg/kg;B组(对照)组5只,术后胸膜腔注入NS10ml。麻醉后经左股动脉插管测量平均动脉压(MAP),经右股静脉插入5F Swan-Ganz导管连接GOULD RM300型电脑监测血流动力学指标变化。结果表明,胸膜腔注入丁哌卡因后血流动力学指标改变轻微,注药前、后比较及两组间比较,差异不  相似文献   
24.

Objective

Liver transplantation carries major risks during the perioperative period. Few studies focused on the hemodynamics of patients undergoing liver transplantation. The present study was aimed to evaluate the impact of the implementation of a protocol including goal-directed therapy in patients undergoing liver transplantation. Our first goal was to determine its impact on the fluid balance. Secondarily, we evaluated possible improvements in the patient outcomes.

Study design

A before and after study.

Patients and methods

Fifty patients undergoing liver transplantation were included during two successive six-month periods. During the first period, the management of the patients was left at the discretion of the senior physicians (control group, n = 25). During the second period, the patients were treated according to a predetermined protocol including a specific hemodynamic monitoring (protocol group, n = 25).

Results

The fluid balance was negative in the protocol group and positive in the control group at 24 h (−606 mL vs. +3445 mL, P < 0.01) and 48 h (−2315 mL vs. +1170 mL, P < 0.01) after liver transplantation. The volume of the crystalloid administration was lower in the protocol group than in the control group (5000 mL vs. 8000 mL, P < 0.01, and 1500 mL vs. 6000 mL, P < 0.01, during surgery and 48 h after liver transplantation, respectively). The duration of mechanical ventilation and postoperative ileus were significantly reduced in the protocol group, as compared with the control group, 20 h vs. 94 h (P < 0.01) and 4 days vs. 6 days (P < 0.01), respectively.

Conclusion

For patients undergoing liver transplantation, the implementation of a protocol aiming to optimize hemodynamics was associated with reduced fluid balance and decreased requirement for mechanical ventilation and postoperative ileus duration.  相似文献   
25.
26.
AimsThe time constant of left ventricular (LV) relaxation derived from a monoexponential model is widely used as an index of LV relaxation rate, although this model does not reflect the non-uniformity of ventricular relaxation. This study investigates whether the relaxation curve can be better fitted with a “quadratic” model than with the “conventional” monoexponential model and if changes in the LV relaxation waveform due to acute myocardial ischemia could be better detected with the quadratic model.Methods and resultsIsovolumic relaxation was assessed with quadratic and conventional models during acute myocardial ischemia performed in 6 anesthetized pigs. Mathematical development indicates that one parameter (Tq) of the quadratic model reflects the rate of LV relaxation, while the second parameter (K) modifies the shape of the relaxation curve. Analysis of experimental data obtained in anesthetized pigs showed that the shape of LV relaxation consistently deviates from the conventional monoexponential decay. During the early phase of acute myocardial ischemia, the rate and non-uniformity of LV relaxation, assessed with the quadratic function, were significantly enhanced. Tq increased by 16% (p < 0.001) and K increased by 12% (p < 0.001) within 30 and 60 min, respectively, after left anterior descending (LAD) coronary artery occlusion. However, no significant changes were observed with the conventional monoexponential decay within 60 min of ischemia.ConclusionsThe quadratic model better fits LV isovolumic relaxation than the monoexponential model and can detect early changes in relaxation due to acute myocardial ischemia that are not detectable with conventional methods.  相似文献   
27.
目的观察右美托咪啶应用于幕上病灶切除术后镇静作用的临床效果。方法选择幕上病灶切除术后患者40例(均在麻醉恢复室),年龄18~60岁,随机分为两组,每组20例。试验组:10min静脉泵注右美托咪啶0.8μg/kg后,以0.6μg.kg-1.h-1维持40min;对照组:10min静脉泵注生理盐水10ml后,20ml生理盐水静脉泵注40min。记录患者血压、心率、呼吸等变化,观察给药后患者镇静作用以及不良反应的发生情况。结果试验组给入右美托咪啶后HR、MAP均低于基础值,对比对照组差异具有统计学意义(P<0.05);RR各个时间点则无明显变化;试验组均达到Ramsay镇静分级Ⅳ级状态。结论右美托咪啶(负荷量0.8μg/kg,维持0.6μg.kg-1.h-1)应用于幕上病灶切除术后患者取得了满意的镇静效果。  相似文献   
28.
Dynamic estimates of mean systemic pressure based on a Guytonian analog model (Pmsa) appear accurate under baseline conditions but may not remain so during septic shock because blood volume distribution and resistances between arterial and venous beds may change. Thus, we examined the effect of acute endotoxemia on the ability of Pmsa, estimated from steady-state cardiac output, right atrial pressure, and mean arterial pressure, to reflect our previously validated instantaneous venous return measure of mean systemic pressure (Pmsi), derived from beat-to-beat measures of right ventricular stroke volume and right atrial pressure during positive pressure ventilation. We studied 6 splenectomized pentobarbital-anesthetized close chested dogs. Right ventricular stroke volume was measured by a pulmonary arterial electromagnetic flow probe. Instantaneous venous return measure of mean systemic pressure and Pmsa were calculated during volume loading and removal (± 100-mL bolus increments × 5) both before (control) and 30 minutes after endotoxin infusion (endo). Cardiac output increased (2628 ± 905 vs 3560 ± 539 mL/min; P < .05) and mean arterial pressure decreased (107 ± 16 vs 56 ± 12 mm Hg; P < .01) during endo. Changes in Pmsi and Pmsa correlated during both control and endo (r2 = 0.7) with minimal bias by Bland-Altman analysis (mean difference ± 95% confidence interval, 0.47 ± 5.04 mm Hg). We conclude that changes in Pmsa accurately tracts Pmsi under both control and endo.  相似文献   
29.
The strongest sex differences on any cognitive task, favoring men, are found for tasks that require the mental rotation of three-dimensional objects. A number of studies have explored functional brain activation during mental rotation tasks, and sex differences have been noted in some. However, in these studies there was a substantial confounding factor because male and female subjects differed in overall performance levels. In contrast, our functional brain activation study examined cortical activation patterns for males and females who did not differ in overall level of performance on three mental rotation tasks. This allowed us to eliminate any confounding influences of overall performance levels. Women exhibited significant bilateral activations in the intraparietal sulcus (IPS) and the superior and inferior parietal lobule, as well as in the inferior temporal gyrus (ITG) and the premotor areas. Men showed significant activation in the right parieto-occitpital sulcus (POS), the left intraparietal sulcus and the left superior parietal lobule (SPL). Both men and women showed activation of the premotor areas but men also showed an additional significant activation of the left motor cortex. No significant activation was found in the inferior temporal gyrus. Our results suggest that there are genuine between-sex differences in cerebral activation patterns during mental rotation activities even when performances are similar. Such differences suggest that the sexes use different strategies in solving mental rotation tasks.  相似文献   
30.
颈动脉支架成形术中血液动力学的变化及其对策   总被引:2,自引:0,他引:2  
目的:观察颈动脉支架成形术中血液动力学不稳定的发生率及其相关因素。方法:15例症状性颈动脉狭 窄患者在行血管内支架成形术时,观察其血压、心率的变化以及药物控制的疗效、围手术期有无并发症。结果:15例支 架放置全部成功,其中11例在进行颈动脉分叉部球囊扩张或支架释放时出现不同程度的心率减慢和血压下降,6例出 现颈动脉窦反应,在使用阿托品和多巴胺后均恢复正常。术中及术后无与血液动力学相关的脑低灌注或高灌注并发症。 结论:血液动力学不稳定是CAS中较为常见的并发症,可通过药物加以控制。  相似文献   
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