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71.
目的探究超声测量颈内静脉内径呼吸变异度和血流速度在椎管内麻醉后血容量判断中的价值。方法选择我院2017年2月至2019年2月择期手术的椎管内麻醉患者120例,男64例,女56例,年龄为34~66岁,ASAⅠ或Ⅱ级。记录麻醉前、麻醉后5、15、25 min左侧颈内静脉最大直径(Dmax)、最小直径(Dmin)、内径呼吸变异度(RVI)、中心静脉压(CVP)、血流速度最大值(BVmax)、血流速度最小值(BVmin)和血流速度变异度(BVI),取CVP=6 mmHg作为预测值,并通过绘制ROC曲线来评估Dmax、Dmin、RVI、BVmax、BVmin和BVI的预测效能。结果与麻醉前比较,麻醉后5 min时Dmax、Dmin和BVI明显降低(P0.05),RVI明显升高(P0.05);与麻醉后5和15 min比较,麻醉后25 min,Dmax、Dmin和BVI明显升高(P0.05),RVI明显降低(P0.05)。麻醉前BVmin的AUC值最大为0.958,临界值6.86,敏感性82.6%,特异性95.2%;麻醉后5 min,Dmin的AUC值最大为0.944,临界值0.74,敏感性98.4%,特异性84.3%;麻醉后15 min,Dmin和BVmax的AUC值最大分别为0.949和0.945,临界值分别为0.72和7.99,敏感性分别为96.5%和89.8%,特异性分别为82.4%和82.1%;麻醉后25 min,BVmax的AUC值最大为0.981,临界值8.98,敏感性92.0%,特异性90.5%。结论超声测量患者颈内静脉的内径变异度和血流速度可作为预测椎管内麻醉后血容量的方式。 相似文献
72.
Moises Rodriguez-Gonzalez Antonio Moruno Tirado Reza Hosseinpour Jose Santos de Soto 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(4):350-356
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic. 相似文献
73.
74.
Aaron Pitzele Mohammad Rahimi Eric Armbrecht 《The journal of maternal-fetal & neonatal medicine》2015,28(15):1770-1773
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion. 相似文献
75.
Improvement in Tricuspid Annular Plane Systolic Excursion with Pulmonary Hypertension Therapy in Pediatric Patients 下载免费PDF全文
76.
目的:探讨彩色多普勒超声诊断卵巢肿瘤蒂扭转的临床意义。方法方便选取2012―2015年该院收治的58例疑似卵巢肿瘤蒂扭转患者作为观察目标,入选病例均应用彩色多普勒超声进行检查,并将检查结果同术后病理检查结果进行比较。结果58例患者中,术后病理证实卵巢肿瘤蒂扭转者51例,彩色多普勒超声共确诊49例,检查准确率为96.1%;囊壁增厚、腹腔或盆腔积液、可见混合型团块是卵巢肿瘤蒂扭转的主要彩超表现。结论卵巢肿瘤蒂扭转应用彩色多普勒超声诊断,可显著提高诊断准确率,具有积极的临床使用和推广价值。 相似文献
77.
对医院野战医疗队与部队卫生机构联合编组救护所参加大型跨区演练活动进行总结,并梳理联合救护所在演训和保障过程中存在的问题和困难,具有较好的现实参考意义,丰富我军卫勤部队与部队卫勤联合演训的理论。 相似文献
78.
19 F MRSI of capecitabine in the liver at 7 T using broadband transmit–receive antennas and dual‐band RF pulses 下载免费PDF全文
Jetse S. van Gorp Peter R. Seevinck Anna Andreychenko Alexander J. E. Raaijmakers Peter R. Luijten Max A. Viergever Miriam Koopman Vincent O. Boer Dennis W. J. Klomp 《NMR in biomedicine》2015,28(11):1433-1442
Capecitabine (Cap) is an often prescribed chemotherapeutic agent, successfully used to cure some patients from cancer or reduce tumor burden for palliative care. However, the efficacy of the drug is limited, it is not known in advance who will respond to the drug and it can come with severe toxicity. 19 F Magnetic Resonance Spectroscopy (MRS) and Magnetic Resonance Spectroscopic Imaging (MRSI) have been used to non‐invasively study Cap metabolism in vivo to find a marker for personalized treatment. In vivo detection, however, is hampered by low concentrations and the use of radiofrequency (RF) surface coils limiting spatial coverage. In this work, the use of a 7T MR system with radiative multi‐channel transmit–receive antennas was investigated with the aim of maximizing the sensitivity and spatial coverage of 19 F detection protocols. The antennas were broadband optimized to facilitate both the 1H (298 MHz) and 19 F (280 MHz) frequencies for accurate shimming, imaging and signal combination. B1+ simulations, phantom and noise measurements showed that more than 90% of the theoretical maximum sensitivity could be obtained when using B1+ and B1? information provided at the 1H frequency for the optimization of B1+ and B1? at the 19 F frequency. Furthermore, to overcome the limits in maximum available RF power, whilst ensuring simultaneous excitation of all detectable conversion products of Cap, a dual‐band RF pulse was designed and evaluated. Finally, 19 F MRS(I) measurements were performed to detect 19 F metabolites in vitro and in vivo. In two patients, at 10 h (patient 1) and 1 h (patient 2) after Cap intake, 19 F metabolites were detected in the liver and the surrounding organs, illustrating the potential of the set‐up for in vivo detection of metabolic rates and drug distribution in the body. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
79.
Dynamic LVOT Obstruction and Aortic Stenosis in the Same Patient: A Case of Challenging Doppler Hemodynamics 下载免费PDF全文
Matthew W. Parker M.D. Francis J. Kiernan M.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(6):1030-1032
We present a patient with both dynamic left ventricular outflow tract obstruction and valvular aortic stenosis. The aortic valve was calcified, and velocities and gradients measured by continuous‐wave Doppler met standard criteria for severe aortic stenosis. The increased subvalvular velocities invalidated assumptions of the simplified Bernoulli equation; correction using the longer form of the Bernoulli equation suggested a lower but still significant gradient. The complex shape of the subvalvular spectral Doppler envelope indicated supranormal systolic function and dynamic left ventricular outflow obstruction. Left heart catheterization with an end‐hole catheter was required to determine the subvalvular and valvular components of the obstruction. 相似文献
80.
《Clinical neurophysiology》2021,132(12):3104-3115
ObjectiveWe aimed to establish an objective neurophysiological test protocol that can be used to assess the somatosensory nervous system.MethodsIn order to assess most fiber subtypes of the somatosensory nervous system, repetitive stimuli of seven different modalities (touch, vibration, pinprick, cold, contact heat, laser, and warmth) were synchronized with the electroencephalogram (EEG) and applied on the cheek and dorsum of the hand and dorsum of the foot in 21 healthy subjects and three polyneuropathy (PNP) patients. Latencies and amplitudes of the modalities were assessed and compared. Patients received quantitative sensory testing (QST) as reference.ResultsWe found reproducible evoked potentials recordings for touch, vibration, pinprick, contact-heat, and laser stimuli. The recording of warm-evoked potentials was challenging in young healthy subjects and not applicable in patients. Latencies were shortest within Aβ-fiber-mediated signals and longest within C-fibers. The test protocol detected function loss within the Aβ-fiber and Aδ-fiber-range in PNP patients. This function loss corresponded with QST findings.ConclusionIn this pilot study, we developed a neurophysiological test protocol that can specifically assess most of the somatosensory modalities. Despite technical challenges, initial patient data appear promising regarding a possible future clinical application.SignificanceEstablished and custom-made stimulators were combined to assess different fiber subtypes of the somatosensory nervous system using modality-specific evoked potentials. 相似文献