High-Frequency Irreversible Electroporation Using 5,000-V Waveforms to Create Reproducible 2- and 4-cm Ablation Zones—A Laboratory Investigation Using Mechanically Perfused Liver

PurposeTo investigate if high-frequency irreversible electroporation (H-FIRE) treatments can be delivered at higher voltages and with greater energy delivery rates than currently implemented in clinical irreversible electroporation protocols.Materials and MethodsTreatments using 3,000 V and 5,000 V were administered to mechanically perfused ex vivo porcine liver via a single applicator and grounding pad (A+GP) as well as a 4-applicator array (4AA). Integrated energized times (IET) 0.01–0.08 seconds and energy delivery rates 25–300 μs/s were investigated. Organs were preserved at 4°C for 10–15 hours before sectioning and gross analysis using a metabolic stain to identify the size and shape of ablation zones.ResultsA+GP ablations measured between 1.6 cm and 2.2 cm, which did not increase when IET was increased from 0.02 seconds to 0.08 seconds (P > .055; range, 1.9–2.1 cm). Changes in tissue color and texture consistent with thermal damage were observed for treatments with energy delivery rates 50–300 μs/s, but not for treatments delivered at 25 μs/s. Use of the 4AA with a 3-cm applicator spacing resulted in ablations measuring 4.4–4.9 cm with energy delivery times of 7–80 minutes.ConclusionsH-FIRE treatments can rapidly and reproducibly create 2-cm ablations using an A+GP configuration. Treatments without thermal injury were produced at the expense of extended treatment times. More rapid treatments resulted in ablations with varying degrees of thermal injury within the H-FIRE ablation zone. Production of 4-cm ablations is possible using a 4AA.     

Investigation of hearing loss in patients with acute brucellosis by standard and high-frequency audiometry

This study aimed to determine the effect of acute brucellosis on the auditory system. Forty-two patients with acute brucellosis were evaluated clinically, and with serological and audiological tests, before and after treatment. Hearing threshold averages were calculated at 11 different frequencies (250-8000 Hz) of the auditory airway, and statistical analysis was performed. The average hearing thresholds were > 20 dB, with standard audiometry at 6000-8000 Hz, and < 20 dB at all other frequencies. After treatment, the average auditory threshold decreased to < 20 dB at 6000-8000 Hz (p < 0.0001). Pure-tone hearing thresholds were improved at all frequencies after treatment, with statistically significant differences at all frequencies except 12,000, 14,000 and 16 000 Hz (p < 0.05). There was no permanent hearing loss caused by acute brucellosis, and hearing thresholds were restored after treatment. It was concluded that acute brucellosis affects the auditory system, especially at high frequencies, and that patients with all forms of brucellosis should be evaluated for hearing loss.     

基于虚拟仪器技术的高频电刀波峰因子检测与验证

提出了一种有效易行的高频电刀波峰因子检测系统的软、硬件设计方案。利用电磁感应原理接收电刀输出波形,由普通的数字示波器完成数据采集与数字化,基于虚拟仪器技术的PC端软件根据数据计算波峰因子。通过对高频电刀波峰因子的检测,最终验证波峰因子对电刀性能以及临床使用效果的重要性。     

超声心动图评价大鼠异位移植心脏急性排斥反应的初步实验研究

目的:探讨高频超声心动图评价大鼠颈部异位移植心脏的急性排斥反应的价值。方法:采用高频超声心动图测量17只同种异体移植及6只同系移植心脏测量左室内径、心肌厚度、左室重量和心功能等。6只同系移植大鼠和9只同种异体移植大鼠,分别于移植术后第1、3、5天,采用高频超声对上述指标进行测量,第五天测量完毕后处死并做病理检查。另8只同种异体移植心脏,分别于移植术后第1、3天各测量一次,第3天测量完毕后处死做病理学检查,超声指标与病理结果相对照。结果:①同种异体移植术后,随着移植时间的延长,左室心肌厚度和左室重量逐渐增加,左室内径减小,射血分数无显著性改变;②术后第3天,组织学检查表明已有排斥反应发生,超声检查显示室壁厚度与左室重量明显增加,而常规心脏触诊未能及时发现排斥反应;③随着组织学分级加重显示的排斥,左室心肌厚度与左室重量有显著的增加。结论:室壁厚度和左室重量为超声评价排斥反应发生的敏感、准确指标。高频超声为心脏移植实验研究评价排斥反应提供了一种较为简便可靠的观察方法,为临床上心脏移植的排斥反应的超声评价提供了依据。     

Effect of external high-frequency oscillation on severe cardiogenic pulmonary edema

Effective gas exchange can be maintained in animals without endotracheal intubation using external high-frequency oscillation (EHFO). The aim of this study was to evaluate the effect of EHFO in patients with respiratory failure due to severe cardiogenic pulmonary edema. Seven patients were ventilated with EHFO for 2h at 60 oscillations·min⁻¹, with a cuiras pressure of 36 cmH₂O (−26 to +10) and an inspiratory to expiratory ratio of 1:1, with EHFO. Blood gas values and hemodynamic parameters were measured. Significant increases were noted in cardiac index (2.3±0.5 to 2.5±0.5 l·m⁻²;P<0.05), stroke volume index (24±7 to 28±8 ml·m⁻²;P<0.05), and arterial O₂ pressure (Pao₂) (70±4 to 95±23 mmHg;P<0.01) without a change in pulmonary artery wedge pressure at 1 h after EHFO. The respiratory rate decreased from 28±3 to 22 ±3 breaths·min⁻¹ at 5 min after the termination of EHFO (P <0.01). Arterial CO₂ pressure (Paco₂) did not, however, decrease. Increased stroke volume without a change in pulmonary artery wedge pressure (preload) suggests either improved inotropic function of the left ventricle or reduced left ventricular afterload with EHFO. The use of EHFO may be effective not only for gas exchange but also for left ventricular function in patients with severe cardiogenic pulmonary edema.     

Effects of synchronization in the pacemaker during high-frequency atrial stimulation

I. M. Sechenov Medical Academy, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 5, pp. 454–456, May, 1991.     

电阻抗扫描成像和高频超声诊断小乳腺癌的对照研究

目的：评价电阻抗扫描成像(electrical impedance scanning，EIS)和高频超声对小乳腺癌的诊断价值．方法：乳腺肿块(直径≤2cm)54例病理证实，行EIS和高频超声检查，时间间隔不超过3d．结果：乳腺癌23例，EIS诊断小乳腺癌17例，敏感性73．9％，特异性80．6％，准确性77．8％，阳性预测值73．9％，阴性预测值80．6％；高频超声诊断小乳腺癌20例，敏感性87．0％，特异性87．1％，准确性87．0％，阳性预测值83．3％，阴性预测值90．0％．二联合诊断，敏感性95．6％，特异性90．3％，准确性92．6％，阳性预测值88．0％，阴性预测值96．6％．结论：EIS对小乳腺癌的诊断有较大实用价值，且与高频超声结合应用，可以提高小乳腺癌的诊断准确奎．     

不同机械通气方式联合猪肺磷脂注射液治疗新生儿呼吸衰竭疗效比较

目的 比较常频机械通气(CMV)、猪肺磷脂注射液联合CMV、猪肺磷脂注射液联合高频振荡通气(HFOV)治疗新生儿呼吸衰竭的疗效。方法 选择2019年1月至2020年12月南阳市中心医院收治的133例呼吸衰竭新生儿为研究对象,根据治疗方式将患儿分为对照组(n=41)、观察组A(n=45)和观察组B(n=47)。对照组患儿给予单纯CMV治疗,观察组A患儿给予猪肺磷脂注射液联合HFOV治疗,观察组B患儿给予猪肺磷脂注射液联合CMV治疗。比较3组患儿机械通气时间、用氧时间、治疗前后的呼吸力学指标[动脉血氧分压(PaO₂)、动脉血二氧化碳分压(PaCO₂)、氧合指数(OI)、呼吸指数(RI)]和血清内皮素-1(ET-1)、肌酸激酶同工酶(CK-MB)、Ⅱ型肺泡表面抗原-6(KL-6)、Clara细胞蛋白16(CC16)水平及不良反应发生情况。结果 3组患儿的机械通气时间和用氧时间比较差异有统计学意义(F=12.658、26.196,P<0.05);观察组A和观察组B患儿的机械通气时间和用氧时间显著短于对照组(P<0.05),观察组A患儿的机...     

HFJV联合药物治疗兔海水淹溺肺水肿

目的：观察高频喷射通气（HFJV）联合4种药物治疗海水淹溺肺水肿（PE-SWD）的效果并探讨其作用机制。方法：用海水灌注的方法诱导PE-SWD模型,采用HFJV联合地塞米松、东莨菪碱、尼莫地平和果糖二磷酸钠4种药物进行治疗,观察记录相关的生理、生化指标。结果：HFJV联合4种药物治疗能明显改善PE-SWD相关指标。结论：HFJV联合4种药物治疗能有效治疗PE-SWD,可作为其基础治疗。