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1.
主动呼吸控制技术(ABC)在肺癌放射治疗中的应用 总被引:1,自引:0,他引:1
目的:使用主动呼吸控制技术(aetive brething control,ABC)治疗非小细胞肺癌患者,评价呼吸运动时肺部肿瘤动度的影响及ABC技术的优势和可行性,并评价近期疗效和急性放射反应。方法:选择9例使用ABC技术联合三维造型放疗技术治疗的非小细胞系癌患者进行分析。CT定位扫描时分别采集ABC和自由呼吸(free breath.FB)状态下的图像,评价呼吸运动对肺部肿瘤动度和PTV边界的影响唾弃;并比较两种计划的DVH,放疗剂量为54-60Gy/18-20次。3Gy/次,1次/天,5天/周,定期随访,评价近期疗效及急性放射反应。结果:应用ABC技术后,隔肌的平均位移从FB时的43.5mm(20.0-32.0mm)降低为3.6mm(0.5-72.mm),胸壁的侧方位移从FB时的3.2mm(2.8-4.0mm)降低为1.2mm(0.5-1.6mm).PTV边界可以从FB时的1.5mm减少为0.75cm;肺的V20从21.8%降低为15.0%,减少了30.6%.中位随访6个月时,9例患者中有6例CR,3例PR.急性放射副反应都很轻微,仅为I-II.结论:在肺癌的精确放射治疗中,呼吸动度的影响不可忽视.而ABC系统可以有效的降低呼吸运动时治疗的影响,提高放疗的精确性,减少副反应.,但该系统使用较为复杂,延长了治疗的时间,个别患者不能忍受. 相似文献
2.
目的了解郑州市围产儿总唇裂畸形的发病情况及年度和城乡分布的特点。方法采用以医院为基础的监测方法收集资料,调查郑州市14所医院内住院分娩的孕28周一产后7天的围产儿。结果郑州市围产儿总唇裂发生率为15.12/万,其中唇裂为4.82/万,唇裂合并腭裂为10.29/,城镇发生率为13.37/万,乡村为20.15/万,男性为16.08/万,女性为13.92/万,总唇裂产妇年龄组别发生率差异有显著性,在≥35岁年龄组最大。年度发生率无长期趋势。总唇裂以单发形式多见,占91.54%,总唇裂畸形围产期病死率为25.87%,单发畸形为22.28%,多发畸形为64.71%。结论郑州市总唇裂发生率无下降趋势,乡村高于城镇。 相似文献
3.
Jen auo Hirschberg 《Early child development and care》1990,65(1):57-69
During a period of twenty years [1969-1988] the author has observed 614 cases of congenital malformations and noninflammatory diseases of the larynx in infants and young children, Budapest. He summarizes the most characteristic symptoms of laryngeal pathology in infants, and discusses the diagnostic possibilities. Among the latter, spectrographic analyses complemented by auditory evaluation of pathological cry and different breathing noises play an important role. Based on his investigation author differentiates 20 kinds of pathological crying sounds and 4 basic forms of stridor. He describes the acoustic attributes of different pathological sound phenomena and summarizes characteristic voice changes. 相似文献
4.
5.
The Enclosed Magill, Humphrey ADE and the Bain breathing systems are all used for controlled ventilation of the lungs. This study compares the three systems in vitro with a lung model and in clinical practice. No difference was observed, with ventilatory variables commonly used in clinical practice, between the Bain and the ADE, while significantly lower end-tidal carbon dioxide values were observed with the Enclosed Magill (about 7%). Lower fresh gas flows can be used under these circumstances to maintain normocapnia with the Enclosed Magill than either the Bain or the Humphrey ADE. 相似文献
6.
J. Mehlsen K. Pagh J. S. Nielsen L. Sestoft S. L. Nielsen 《Clinical physiology and functional imaging》1987,7(2):115-124
Summary. Heart rate responses to stepwise and periodic changes in lung volume were studied in seven young healthy males. Stepwise inspiration and expiration both resulted in an increase in heart rate followed by a rapid decrease in heart rate. The fastest heart rate was reached in 1·6 ± 0·5 s and in 3·6 ± 1·4 s in response to inspiration and expiration, respectively (P < 0·01). The slowest heart rate was reached in 4·8± 1·0 s and in 7·6± 1·9 s in response to inspiration and expiration, respectively (P < 0·01). Following this biphasic change the heart rate returned to a steady level. The difference between the fastest and the slowest heart rates was significantly larger in response to inspiration (21·7 ± 7·3 beats per minute) than in response to expiration (12·0±7·3 beats per minute; P < 0·01). Periodic changes in lung volume were performed with frequencies from 3·0 to 12·0 respirations per minute (r.p.m.). The changes in heart rate showed a constant amplitude in the frequency range below 5·5 r.p.m. Maximal heart rate changes were found at frequencies of 5·5 to 7·0 r.p.m. Changes in heart rate decreased in a linear manner on a log-log scale in the frequency range above 7·0 r.p.m. The relation between frequency and changes in heart rate is explained by interference between the transient changes in heart rate induced both by inspiration and by expiration. It is concluded that if heart rate changes in response to periodic changes in lung volume are to be used as a measure of vagal function a number of factors have to be taken into consideration and to simplify the analysis of heart rate responses to breathing we recommend, instead, the use of the transient changes in heart rate induced by stepwise changes in lung volume. 相似文献
7.
Johanna Albert Leif Kindlund Barbro Nilvér Waldemar Gożdzik 《Central European Journal of Medicine》2006,1(2):162-171
Abstract: Background: The laryngeal mask airway (LMA) can be used in general anaesthesia without neuromuscular block. The
laryngeal tube (LT) is a new airway device with similar airway features as LMA. LT is provided with a distal cuff to prevent
regurgitation. In this study we compared the LMA and LT concerning patient and user aspects.
Methods: Sixty patients with ASA (American Society of Anestesiologists) score 1–2 scheduled for minor surgery were randomized
to be ventilated either through LMA or LT. After insertion, the number of insertion attempts, and “positioning” and “airway-assessment”
was evaluated. The patients reported on “sore throat” after 30 and 60 minutes and the day after anaesthesia.
Results: Gender and mean age were equal in both groups. The first insertion attempt was successful in 25 of 28 patients randomised
to LMA and in 23 of 27 patients randomised to LT. LMA was evaluated to be easier in “positioning” whereas no difference in
“sore throat” was reported.
Conclusion: We found no difference between the LMA and the LT in terms user and patient friendliness and safety. 相似文献
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9.
We have sought to define a way in which nitrous oxide can be safely and universally used at minimal to low flows by utilising a circle system with a controlled leak provided by a standard gas analyser sampling line and a fresh gas supply of 50% nitrous oxide in oxygen, entering from a trunk interposed between the ventilator and the circle system. Although preliminary calculations suggested that this arrangement was likely to work, it was found that 13 of 23 patients studied prospectively developed an inspired oxygen fraction below 0.3. We conclude that, although this arrangement provides a new means of introducing nitrous oxide into the circle breathing system, it does not appear inherently safer or more convenient than the conventional route. 相似文献
10.
Comparison of the haemodynamic effects of intermittent positive pressure ventilation with high frequency jet ventilation 总被引:1,自引:0,他引:1
The cardiorespiratory effects of intermittent positive pressure ventilation and high frequency jet ventilation with and without positive end expiratory pressure were compared in patients following valvular heart surgery (mitral and/or aortic). Twenty patients received intermittent positive pressure ventilation and high frequency jet ventilation with 0, 0.5 and 1.0 kPa positive end expiratory pressure. High frequency jet ventilation was well tolerated. The addition of 1.0 kPa positive end expiratory pressure was associated with preservation of the arterial oxygen tension without any increase in shunt or significant adverse haemodynamic effect. The results are discussed and compared with a previous study of high frequency jet ventilation following aortocoronary bypass graft surgery. 相似文献