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101.
Measurements of respiratory mechanics are frequently made in ventilated infants and children. Esophageal pressure measurements (Pes using a balloon on a catheter have been used to partition the respiratory mechanics into lung and chest wall components. Appropriate positioning of this balloon is crucial to obtain accurate estimates of pleural pressure. Traditionally, in spontaneously breathing subjects the balloon position is assessed with an occlusion test. In ventilated subjects, it is not always possible to perform an occlusion test prior to paralysis, and even if such a test is performed it may not be relevant under conditions of positive pressure ventilation. We have assessed a positive pressure occlusion test that is suitable for paralyzed subjects. By occluding the airway opening and applying gentle pressure to the abdomen or rib cage, positive swings in pressure can be measured by both Pes and airway opening pressure (Pao). We compared traditional occlusion tests measured in 16 spontaneously breathing puppies to the positive pressure occlusion test performed after paralysis. In 2 pups we were unable to obtain a reasonable traditional occlusion test (>15% difference between Pes and Pao) but we obtained 10 traditional occlusion tests in each of the remaining 14 pups (2.1–14 kg). In 11 of these animals Ape, was within 10% of Pao. This compared well to positive pressure occlusion test using abdominal pressure performed after paralysis, where Apes was within 10% of ΔPao in 10 animals. In 9 of these pups occlusion tests were also performed by applying pressure on the rib cage, where ΔPes was within 10% of ΔPao in 6 animals. These results suggest that it is possible to perform accurate occlusion tests in paralyzed subjects by abdominal or rib cage compression with the airway occluded. Pediatr Pulmonol. 1994; 17:56–62. © 1994 Wiley-Liss, Inc. 相似文献
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105.
Respiratory symptoms associated with the use of azodicarbonamide foaming agent in a plastics injection molding facility 总被引:1,自引:0,他引:1
L W Whitehead T G Robins L J Fine D J Hansen 《American journal of industrial medicine》1987,11(1):83-92
Respiratory health variables were studied cross-sectionally in 227 employees of a plastics molding facility where numerous complaints had been apparently associated with the use of azodicarbonamide foaming agent in injection molding. Pre- and postshift respiratory status measures and azodicarbonamide concentrations were also obtained for 17 employees. Cross-sectional pulmonary function differences by injection molding status were not observed. Modest decrements in pulmonary function measures were observed between start and end of shift but with no dose-effect relationship. A strong association was observed for injection molding workers for eye/nose/throat irritation, cough, and wheezing. Additionally, wheezing, chest tightness, and symptoms of chronic bronchitis were strongly associated with work in injection molding during periods in which azodicarbonamide was in use. These results suggest respiratory symptom causation by some combination of azodicarbonamide itself, reaction products of azodicarbonamide formed during injection molding, or other unidentified agents uniquely associated with the process of injection molding with azodicarbonamide foaming agent. 相似文献
106.
A. Linneberg I. Hertzum L. L. N. Husemoen N. Johansen T. Jørgensen 《Clinical and experimental allergy》2006,36(6):714-721
BACKGROUND: It has been proposed that alcohol consumption may be one of the lifestyle factors associated with a westernized, urban, and affluent lifestyle contributing to the rise in atopic disease. OBJECTIVE: The aim was to investigate the association between alcohol consumption and atopy (aeroallergen sensitization). METHODS: In 1982, a population-based cross-sectional study of 3608 Danes (79% of the invited), aged 30, 40, 50, and 60 years, was carried out. Information on alcohol consumption was obtained by a questionnaire. Aeroallergen sensitization was defined as a positive test for the detection of specific IgE against a panel of 19 common inhalant allergens in stored serum samples. A total of 3317 subjects with complete information on all variables were included in the analyses. RESULTS: We found a statistically significant association between alcohol consumption and aeroallergen sensitization (independent of the type of alcoholic drink consumed). This association appeared to relate only to those who consumed more than 8 drinks/week. After adjustment for confounders this association was only statistically significant for those who consumed 15-21 drinks/week (adjusted odds ratio 1.8, 95% confidence interval 1.2-2.8). CONCLUSION: In this adult general population, self-reported alcohol consumption was positively associated with aeroallergen sensitization. 相似文献
107.
W. G. Selley FDS Hon FCST R. E. Ellis MPhil F. C. Flack PhD C. R. Bayliss MB B Chir FRCR V. R. Pearce MB FRCP 《Dysphagia》1994,9(3):162-167
Simultaneous recording of adult subjects sipping small amounts of fluid from a cup have been obtained by videofluoroscopy together with feeding respiratory patterns and swallow sounds from the Exeter Dysphagia Assessment Technique (EDAT). These allowed visual representations of respiration and swallow sounds to be superimposed on a videofluoroscopy recording using a split-screen technique. Sequentially numbered, 1/50 sec, half-frame photographic prints were examined and schematic drawings of the relevant radiographs were made. These were superimposed on to the actual EDAT printed chart of the same swallow event, theri exact time relationship with respiration and cervical swallow sounds being preserved. The results allow events in the barium videofluoroscopy to be related to events in the feeding respiratory pattern and swallow sounds recorded by EDAT. 相似文献
108.
Intraperitoneal chemotherapy was administered to 13 patients with peritoneal carcinomatosis, using acute peritoneal dialysis catheters immediately before the administration of the chemotherapy. A total of 59 cycles were administered, with insertion of the corresponding catheter. There were no inflow or outflow problems and no insertion-related complications. With the removal of the catheter after its use, there is no risk of abdominal infections. 相似文献
109.
G. J. Kemp C. H. Thompson A. L. Sanderson G. K. Radda 《Magnetic resonance in medicine》1994,31(2):103-109
We used 31P magnetic resonance spectroscopy to compare the response of rat skeletal muscle to three kinds of proton load. During exercise (tetanic sciatic nerve stimulation), protons from lactic acid were buffered passively and consumed by net hydrolysis of phosphocreatine (PCr). During recovery from exercise, the pH-dependent efflux of protons produced by PCr resynthesis could be partially inhibited by amiloride or 4,4′-diisothiocyanostilbene-2,2′-disulphonate (DIDS), implicating both sodiudproton and bicarbonatelchloride exchange, but was not inhibited by simultaneous respiratory acidosis. In early recovery, up to 30% of proton efflux was mediated by lactatelproton cotransport. During acute respiratory acidosis at rest, the eventual change in muscle pH was consistent with passive buffering and was unaffected by amiloride or DIDS, implying no significant contribution of proton fluxes. 相似文献
110.
Specific and sensitive diagnosis of syphilis using a real-time PCR for Treponema pallidum 总被引:1,自引:0,他引:1
A. G. Koek S. M. Bruisten M. Dierdorp A. P. van Dam K. Templeton 《Clinical microbiology and infection》2006,12(12):1233-1236
A real-time PCR assay with a Taqman probe was developed that targeted the polA gene of Treponema pallidum. The test was validated using an analytical panel (n = 140) and a clinical panel of genital samples (n = 112) from patients attending a sexually transmitted infections clinic. High sensitivities and specificities of 94-100% were achieved using two real-time PCR platforms, the Rotor-Gene and the iCycler. The assay can be completed within 2 h, enabling reporting in <8 h. This fast and robust assay is suitable for implementation in routine laboratories for diagnosing primary syphilis. 相似文献