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Capnographic documentation of nasoesophageal and nasogastric feeding tube placement in dogs 总被引:1,自引:0,他引:1
Paula A. Johnson DVM F. A. Mann DVM MS DACVS DACVECC John Dodam DVM MS PhD DACVA Keith Branson DVM MS DACVA Colette Wagner-Mann DVM PhD Mark A. Brady DVM Elizabeth Dunphy DVM 《Journal of Veterinary Emergency and Critical Care》2002,12(4):227-233
Objective: To evaluate the ability of capnography to document proper placement of nasoesophageal (NE) and nasogastric (NG) feeding tubes. This study was conducted in 3 phases. Phase I of this study was designed in order to test the efficacy of capnography to distinguish placement of a feeding tube in the alimentary tract versus the respiratory tract. Phase II was designed in order to document that carbon dioxide (CO2) could be measured through a polyvinyl chloride (PVC) feeding tube. Phase III was performed in order to evaluate the technique of continuous monitoring during insertion of the feeding tube into the esophagus and stomach as would be performed during a clinical‐tube placement. Design: Prospective study. Setting: Research laboratory. Animals: 24 adult dogs. Interventions: In Phase I, sedated dogs were instrumented with an intratracheal catheter and an 8 French feeding tube placed nasally into the distal esophagus and later advanced into the stomach. In Phase II, dogs were anesthetized and an 8 French feeding tube was placed down the endotracheal tube, then into the esophagus and later advanced into the stomach. In Phase III, sedated dogs were instrumented with an 8 French feeding tube inserted intranasally and then advanced to the level of the nasopharynx, distal esophagus and, lastly, the stomach. Fluoroscopy was used in order to determine location of the feeding tube. Measurements and main results: Phase I measurements included respiratory rate and CO2 from the trachea, esophagus, and stomach and pH of gastric fluid sample. Phase II measurements included respiratory rate and CO2 from the endotracheal tube, feeding tube in the endotracheal tube, feeding tube in the distal esophagus, and feeding tube in the stomach. Phase III data collection included respiratory rate and CO2 as the tube was passed through the nasal cavity, nasopharynx, esophagus and stomach. Phase I fluid samples were collected from 5 of the 9 dogs and had pH values from 1.68 to 4.20. In both phases, values for the respiratory rate and CO2 from the esophagus and stomach were 0 ± 0, significantly lower (P < 0.001) than the values from the trachea. In Phase II, there was no significant difference between the respiratory rates (P = 0.886) and CO2 (P = 0.705) readings obtained from the endotracheal tube compared to readings from the feeding tube in the endotracheal tube. In Phase III, there was a significant difference (P < 0.001) between the respiratory rates and CO2 readings obtained from the nasal cavity and the nasopharynx when compared to those readings obtained from the esophagus and stomach. Measurement of CO2 and respiratory rate resulted in a reading of 0 every time the feeding tube was in the esophagus or stomach. Conclusions: Capnography may be used in order to detect airway placement of NE and NG tubes. 相似文献
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控制sch单养雄蚕品种雌雄蚕孵出比例的催青处理因素研究 总被引:1,自引:1,他引:0
研究结果表明 :在RH 6 0 %状态下 ,控制性比的温度和下限时间负相关达到显著水平 ;控制性比的高温处理适于干燥状态下进行 ;处理后雌蚕孵化整齐度明显低于雄蚕孵化整齐度 ,雌雄蚕孵化整齐度均随处理温度的升高而下降 ,尤以雌蚕更为明显。由此提出了在RH 6 0 %状态下sch单养雄蚕品种控制性比的起点温度及温度、时间范围。认为高温催青用下限温度配合 1日收蚁法效果好 ,高温处理以后的胚胎适于在RH 80 %~ 85 %的湿度中保护 相似文献
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牛磺酸在猫营养中的应用 总被引:1,自引:0,他引:1
主要综述近年猫的牛磺酸营养,从研究方法来看衡量牛磺酸利用的方法与指标已较完善,对牛磺酸的代谢有了深入的了解,并进一步关注猫肠道菌群影响牛磺酸代谢的机理的研究;初步揭示大豆蛋白和脂肪等营养物质降低牛磺酸利用率的原因;在猫粮加工方面指出不良热处理导致的猫粮中牛磺酸利用率降低的机制,并分析了一些不适合配制猫粮的原料如米糠、大豆蛋白对牛磺酸代谢的影响;以及在猫粮中直接添加晶体牛磺酸的重要性。从文中可以看到,作为必需氨基酸的牛磺酸对于猫的生长繁殖来说十分重要。 相似文献
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在西苏旗对蒙古冰草的种子产量及产量构成因子进行了分析得出结果为冰草的实际种子产量与潜在种子产量差别很大,蒙古冰草种子产量的主要限制因子为抽穗率和结实率。 相似文献
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