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71.
A chromium electroplating worker, suffering from epistaxis during work, was found to have nasal septum perforation. To determine the etiology and prevalence of nasal septum lesions, we conducted a survey of seven chromium electroplating factories and examined 79 workers. Forty workers from three aluminum electroplating factories were also enrolled as the reference group. Subjects were thoroughly examined by an otolaryngologist and each of them provided a blood and urine sample. A questionnaire interview regarding symptoms of the upper respiratory tract, past medical history, life style, and work history was also conducted. Air chromium concentrations were measured by taking area samples for 4–6 hours. Based on field observation and chromium measurements, we divided chromium electroplating into three different exposure zones: workers directly dealing with electroplating tanks (n = 31), other process workers (n = 29), and office workers and drivers (n = 19). Among the 79 chromium electroplating workers, there were 16 cases of nasal septum perforation, and 42 with either scar formation or ulceration; 10 chromium electroplating workers developed skin ulcers after performing chrome plating. No workers from aluminum electroplating factories had any nasal septum or skin abnormalities. There was a consistent trend between the degree of chromium exposure and the signs and symptoms related to the nose, throat, and skin. Immediate improvement of occupational hygiene is warranted.  相似文献   
72.
吗啡对机械通气病人的应用   总被引:1,自引:0,他引:1  
为获得病人在接受呼吸机期间充分的镇静、良好的耐管并与呼吸机合拍达到满意的治疗效果,对60例不同年龄的患者在进行呼吸机支持治疗期间,采用平均045mg/(kgd)的吗啡量持续微量泵静脉注入,间断辅助安定的方法.用药后连续2h观察血压、心率、呼吸、意识等变化.结果:在用药期间病人血压、心率、呼吸平稳,保持清醒,安静耐管,解决了病人与呼吸机拮抗的矛盾.结果表明:该法在临床上有广泛使用价值  相似文献   
73.
Background: Hypoxic pulmonary vasoconstriction has an important role in human one-lung ventilation (OLV) in the lateral decubitus position under general anesthesia. During OLV, inhalational anesthesia may inhibit hypoxic pulmonary vasoconstriction and the decrease in arterial oxygenation. We studied the effect of isoflurane administration on arterial oxygen tension in chronic obstructive pulmonary disease patients.
Methods: Ten patients who had thoracoscopic laser ablation of bullous emphysema were studied. Patients received 2% isoflurane in oxygen from induction until the first 20 min of OLV in the lateral decubitus position, then were switched to 1% isoflurane lasting 20 min and next were switched to 0.5% isoflurane lasting 20 min. After each 20-min inhalation, pulmonary and hemodynamic parameters were measured. The given concentrations for isoflurane were merely vapor meter concentrations.
Results: PaO2/FIO2, Qs/Qt respiratory rate peak inspiratory pressure and PaCO2 showed no significant changes at each point of isoflurane. Expiratory tidal volume significantly decreased (P<0.05) with 0.5% isoflurane compared to that with 2% isoflurane. Cardiac output, mean arterial pressure, mean pulmonary arterial pressure, systemic vascular resistance and pulmonary vascular resistance showed no significant changes at each point of isoflurane.
Conclusions: In patients with pulmonary emphysema, arterial oxygenation is not affected by low isoflurane concentration during OLV in the lateral decubitus position.  相似文献   
74.
The construction of a breathing lung phantom that can be used to measure the amount of radioactive gas in the lungs as well as to determine the absorbed dose is described. For a lung ventilation study that consists of 6 views of 300 kents each, an effective dose equivalent of 50 Sv was calculated. The phantom is also suitable for comparison of different generator systems.  相似文献   
75.
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...  相似文献   
76.
目的 探究慢性阻塞性肺疾病急性加重期(AECOPD)有创机械通气患者营养风险及影响因素分析。方法 选取2020年2月—2022年2月入住中国医科大学附属盛京医院重症监护病房(ICU)需要有创机械通气支持的AECOPD患者126例,根据营养风险筛查量表(NRS)2002将患者分为有营养风险组(86例)和无营养风险组(40例)。收集患者动脉血氧分压(PaO2)、动脉血二氧化碳分压(PaCO2)、第1秒用力呼气容积占用力肺活量百分比(FEV1/FVC)、残气量(RV)、白蛋白(ALB)、前白蛋白(PA)等临床资料。采用多因素一般Logistic回归分析有创机械通气AECOPD患者发生营养风险的危险因素,绘制受试者工作特性(ROC)曲线评价上述指标对有创机械通气AECOPD患者营养风险的诊断价值。结果 有营养风险组PaO2<60 mmHg、PaCO2≥50 mmHg、FEV1/FVC<50%、ALB<30.00 g/L、PA<145.00 ...  相似文献   
77.
A system composed of a functional continuous magnetic stimulator (FCMS) and a saddle-type coil has been developed for non-invasive treatment of urinary incontinence, especially stress incontinence and urge incontinence. The FCMS conditions were as follows: 2 kW maximum electrical power consumption, 800 V maximum capacitor voltage, 720 μs pulsewidth (180 μs rise time), and 5–30 Hz frequency. A frequency between 5 and 10 Hz is used to treat urge incontinence and a frequency between 25 Hz and 30 Hz is used to treat urge incontinence. The coil (120 mm long, 90 mm wide and 50 mm thick) fits the most suitable region for this treatment, the region from the anus to the perineum. The coil is cooled to maintain a coil temperature between 20 and 25°C so that it can be used efficiently and safely. In experiments with anaesthetised dogs, it was confirmed that the urethral pressure increased when the circumference of the perineum received continuous magnetic stimulation of 720 μs pulsewidth (180 μs rise time), 10Hz frequency and about 520 V capacitor voltage. This result suggests that magnetic stimulation can be effective as a urinary incontinence therapy.  相似文献   
78.
The recording of sounds over the oribt of the eye has been found to be useful in the detection of intracranial aneurysms. A hydrophone for auscultation over the eye has been developed and is tested under controlled conditions. The tests consist of measurement over the eyes in three healthy volunteers at rest, during voluntary breathing, during eyeball movements and during sustained orbicular muscular contractions. Furthermore, measurements are performed at the side of the nose. Major features of the hydrophonic transducer are high sensitivity to physiological sounds and a high degree of insensitivity to environmental sounds propagated through the air. It can be concluded that the hydrophone may be useful for the early detection of intracranial aneurysms and also for apnoea detection.  相似文献   
79.
During apneic periods elicited by high-frequency oscillatory ventilation (HFOV) a tonic diaphragmatic activity was observed, contrasting with the absence of diaphragmatic activity during apnea induced by lung inflation. To clarify the mechanism underlying the persistence of the diaphragmatic activity during HFOV-induced arrest of breathing the reflex responses to short periods of HFOV, and to periods of lung inflation with airway pressure (P aw) equal to the meanP aw and/or to maximalP aw during HFOV were examined both before and after the blockade of slowly adapting stretch receptors (SR) by inhalation of sulphur dioxide (SO2) in anaesthetized rabbits. In animals with intact SR, the HFOV-induced reflex apnea lasted longer than that induced by lung inflation, the associated diaphragmatic activity being in the most cases higher than the diaphragmatic activity during quiet expiration; inflation, however, completely inhibited diaphragmatic activity. After blockade of SR, spontaneous breathing continued during periods of lung inflation, i.e., the Hering-Breuer inflation reflex was abolished, whereas HFOV still led to a cessation of spontaneous breathing, the associated diaphragmatic activity even exceeding the level observed during quiet inspiration. From these results we conclude that only one part of the reflex response to HFOV is due to SR-stimulation and that in addition other vagal pulmonary receptors (irritant-and/or C-fibre-receptors) are involved. The stimulation of the latter counterbalances the concomitant stimulation of SR, giving rise to the tonic activity of the diaphragm.  相似文献   
80.
张振英 《医学信息》2007,20(9):793-795
目的探讨不同的吸痰方法,从而有效地清除气管插管患者的呼吸道分泌物。方法对47例气管插管病人均采用常规法和呛咳法两种方法吸痰,呛咳法要求:吸痰管带负压进入气管插管,随吸痰管插入深度调节负压,适时安全吸痰,适度气道湿化。常规法按临床一般方法进行吸痰。将两种方法吸出的痰量,痰液性状及吸痰前后20min血氧饱和度(SpO2)进行比较。结果两种方法在吸出的痰量,痰液性状和SpO2方面存在着显著差异(P<0.05,P<0.01),呛咳法吸出的痰多且粘稠。吸痰后SpO2明显高于吸痰前和常规法。结论呛咳法吸痰能充分吸出气道深部的痰液,可以有效防止气道阻塞,改善通气功能。  相似文献   
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