尿液分析、比重与正确采集

🧠 为什么重要

URINALYSIS正常值：SPECIFIC GRAVITY 1.005到1.030，脱水时偏高，尿崩症或过度水合时偏低；pH约为4.5到8；蛋白质、葡萄糖、酮体、血液和胆红素为阴性；NITRITES和LEUKOCYTE ESTERASE在尿路感染时为阳性。尿中有蛋白质提示肾损伤或子痫前期；当血糖超过约180时会出现葡萄糖；酮体出现在糖尿病酮症酸中毒和饥饿时。A CLEAN-CATCH中段尿标本要求清洁尿道口（女性患者从前向后），先开始排尿，然后将中段尿收集到无菌容器中；从导尿管采集时，应短暂夹闭并用无菌技术从采样口抽取，绝不能从集尿袋采集。标本应在约一小时内送到实验室，否则应冷藏。A 24-HOUR URINE采集从丢弃首次排尿并记录时间开始，然后保存每一次排尿，包括结束时间的那一次，并置于冰上或冷藏；如果漏掉一次排尿，采集需重新开始。尿液CULTURES应在抗生素使用前采集。进行STOOL愈创木脂试验前，应避免红肉、维生素C和NSAIDs；检查虫卵和寄生虫时，应趁温热送检。SPUTUM培养最好在清晨进行，患者用水漱口（不用漱口水），深呼吸并从胸部用力咳出；唾液拭子不是痰液。

URINALYSIS normals: SPECIFIC GRAVITY 1.005 to 1.030, high with dehydration and low with diabetes insipidus or overhydration; pH about 4.5 to 8; protein, glucose, ketones, blood and bilirubin negative; NITRITES and LEUKOCYTE ESTERASE positive in urinary tract infection. Protein in the urine suggests kidney damage or preeclampsia; glucose appears when blood glucose exceeds about 180; ketones appear in diabetic ketoacidosis and starvation. A CLEAN-CATCH midstream specimen requires cleaning the meatus (front to back for a female client), starting the stream, then collecting the middle portion in a sterile container; from a catheter, clamp briefly and draw from the sampling port with sterile technique, never from the bag. Specimens go to the lab within about an hour or are refrigerated. A 24-HOUR URINE collection starts by discarding the first void and noting the time, then saves every void including one at the end time, kept on ice or refrigerated; if a void is missed, the collection restarts. Urine CULTURES are collected before antibiotics. For a STOOL guaiac test, avoid red meat, vitamin C and NSAIDs beforehand; for ova and parasites, deliver warm. SPUTUM cultures are best first thing in the morning, with the client rinsing the mouth with water (not mouthwash), taking deep breaths and coughing from the chest; a swab of saliva is not sputum.

🏥 真实场景

🕐 0700时患者排尿，护士将其丢弃，开始24小时采集。1500时一名助手误将一次排尿倒入马桶。护士重新开始：缺少样本的24小时采集毫无价值，将其报告为完整会误导医务人员。考试会问如何处理漏掉的排尿，诚实的答案是重新开始。

🕐 At 0700 the client voids and the nurse discards it, starting the 24-hour collection. At 1500 an aide empties a void into the toilet by mistake. The nurse starts over: a 24-hour collection with a missing sample is worthless, and reporting it as complete would mislead the provider. The exam asks what to do about the missed void, and the honest answer is restart.

📌 要点总结

• 比重高意味着尿液浓缩和脱水High specific gravity means concentrated urine and dehydration
• 导管样本来自采样口，绝不来自集尿袋；培养应在抗生素使用前采集Catheter samples come from the port, never the bag; cultures before antibiotics
• 24小时采集中漏掉一次排尿意味着重新开始Missed void in a 24-hour collection means restart

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