💊 药理学 · 第5课，共6课 · 8 min
IV液体、钾的规则和输血的前15分钟
IV Fluids, Potassium Rules and the First 15 Minutes of a Transfusion
🩸 钾绝对、绝对不能IV推注。最严重的输血反应通常开始得早，因此护士要待满前15分钟。血液只能与生理盐水一起输注。三条规则，每一条都写在某个人的死亡证明上。
🩸 Potassium is never, ever pushed IV. The worst transfusion reactions usually start early, so the nurse stays for the first 15 minutes. Blood runs only with normal saline. Three rules, each written in someone's death certificate.
💡 核心要点
钾要稀释并用泵输注，切勿推注，并且需要有尿量。血液只能与生理盐水一起输注，两名护士核对，前15分钟在床边，在4小时内完成。反应：停止、生理盐水、通知。
Potassium is diluted and pumped, never pushed, and needs urine output. Blood runs with normal saline only, two-nurse check, first 15 minutes at the bedside, done within 4 hours. Reaction: stop, saline, notify.
🧠 为什么重要
等渗液体（0.9% saline、lactated Ringer's）扩充血管内容量，用于脱水、出血和休克。低渗液体（0.45% saline）将水移入细胞，用于细胞内脱水，但切勿用于颅内压升高或低血压。高渗液体（3% saline、D10W）将水从细胞中拉出；3% saline用于严重低钠血症，并要仔细监测。钾：切勿IV推注，始终稀释并用泵给药；外周速率通常限制在约10 mEq/hr，只有通过中心静脉导管并在监测下才能使用更高速率；先检查尿量，因为钾由肾脏排泄。监测IV部位的渗漏（凉、肿、苍白）和静脉炎（热、红、条索状）；停止输注，拔除导管并在其他部位重新开始。对于外渗的发疱剂，停止输注，断开输液管，从导管回抽，然后拔除它（除非政策规定先通过它给予解毒剂）。抬高肢体，通知医疗提供者，并根据具体药物要求使用热敷或冷敷。血液：由两名持证护士在床边核对患者、血型和血袋；仅使用生理盐水和带过滤器的输液管；缓慢开始并在前15分钟陪伴患者；在输注前、15分钟时和输注后测量生命体征；在离开血库后4小时内完成。对于任何反应（发热、寒战、背痛、呼吸困难、荨麻疹、低血压）：停止输血，用新的生理盐水输液管保持IV通畅，通知医疗提供者和血库，并将血袋和输液管送回。
ISOTONIC fluids (0.9% saline, lactated Ringer's) expand the vascular volume for dehydration, hemorrhage and shock. HYPOTONIC fluids (0.45% saline) move water into cells for cellular dehydration, but never in increased intracranial pressure or hypotension. HYPERTONIC fluids (3% saline, D10W) pull water out of cells; 3% saline is used for severe hyponatremia with careful monitoring. POTASSIUM: never IV push, always diluted and given by pump; peripheral rates are commonly limited to about 10 mEq/hr, with higher rates only through a central line on a monitor; check urine output first, because potassium is excreted by the kidneys. Monitor IV sites for INFILTRATION (cool, swollen, pale) and PHLEBITIS (warm, red, cord-like); stop the infusion, remove the catheter and restart elsewhere. For vesicants that EXTRAVASATE, stop the infusion, disconnect the tubing, aspirate from the catheter, then remove it (unless policy says to give an antidote through it first). Elevate the limb, notify the provider, and use warm or cold compresses as the specific drug requires. BLOOD: two licensed nurses verify the client, the blood type and the unit at the bedside; use only normal saline and a filtered tubing; start slowly and stay with the client for the first 15 minutes; take vital signs before, at 15 minutes and after; complete within 4 hours of leaving the blood bank. For any reaction (fever, chills, back pain, dyspnea, hives, hypotension): STOP the transfusion, keep the IV open with new saline tubing, notify the provider and blood bank, and send the bag and tubing back.
🏥 真实场景
⏱️ 输注一单位浓缩红细胞十分钟后，一名患者说她背痛并感觉发热。护士停止输血，断开血液输液管，挂上新的生理盐水，测量生命体征，并致电医疗提供者和血库。血袋被送回进行检测。她不会“减慢速度并观察”；考试的正确答案总是以停止开始。
⏱️ Ten minutes into a unit of packed cells, a client says her back hurts and she feels hot. The nurse stops the transfusion, disconnects the blood tubing, hangs new saline, takes vital signs and calls the provider and the blood bank. The blood bag goes back for testing. She does not 'slow it down and watch'; the exam's correct answer always starts with stop.
📌 要点总结
- 等渗用于容量，低渗用于细胞（颅内压升高时切勿使用），高渗将液体从细胞中拉出Isotonic for volume, hypotonic for cells (never in raised ICP), hypertonic pulls fluid out of cells
- 钾：稀释、用泵输注，外周最大约10 mEq/hr，先看尿量Potassium: diluted, pumped, max about 10 mEq/hr peripherally, urine output first
- 输血：2名护士、仅生理盐水、待15分钟、4小时限制；反应意味着停止Transfusion: 2 nurses, saline only, stay 15 minutes, 4-hour limit; reaction means stop
📖 本课术语
外渗 (Extravasation): 一种发疱剂（损伤组织的）IV药物（如某些化疗药物）漏入静脉周围组织；非发疱剂的漏出称为浸润。
输血反应 (Transfusion reaction): 输血期间出现发热、寒战、背痛、荨麻疹或低血压；停止输血，并通过新输液管用生理盐水保持管路通畅。
等渗溶液 (Isotonic solution): 一种IV液体，如0.9%生理盐水或乳酸林格液，能扩充血容量，而不会使水进出细胞。
低渗溶液 (Hypotonic solution): 一种IV液体，如0.45%生理盐水，能使水进入细胞，绝不能用于颅内压升高的患者。
Potassium chloride: 补充低钾，但推注过快会使心脏停跳：切勿IV推注，始终稀释并通过输液泵输注（外周通路约每小时10 mEq），先确认尿量；口服剂量随食物和水服用。
Albumin（IV胶体） (Albumin (IV colloid)): 由 混合人血浆制成的胶体，可在休克、烧伤、大量腹腔穿刺和低蛋白状态时将液体拉回血管；无需交叉配血，但要注意输注期间循环超负荷（湿啰音、呼吸困难、血压升高）和过敏反应。
✅ 自我测试
医嘱写着“potassium chloride 40 mEq IV push now”。护士应该怎么做？An order reads 'potassium chloride 40 mEq IV push now.' What should the nurse do?
- 通过中心静脉导管给予Give it through a central line
- 在2分钟内缓慢给予Give it slowly over 2 minutes
- 稀释后在10分钟内给予Dilute it and give it over 10 minutes
- 质疑该医嘱Question the order
答案: D · 质疑该医嘱
IV推注钾会导致致命的心律失常。它必须始终稀释并用泵以受控速率输注。稀释后在10分钟内给予仍然太快；IV钾用泵输注，通常不快于每小时10 mEq。
IV push potassium causes fatal arrhythmias. It must always be diluted and infused by pump at a controlled rate. Diluting it and giving it over 10 minutes is still far too fast; IV potassium is infused by pump, typically no faster than 10 mEq per hour.
输血五分钟后，患者出现寒战、侧腹痛和低血压。护士的第一项措施是什么？Five minutes into a blood transfusion the client develops chills, flank pain and hypotension. What is the nurse's first action?
- 给予acetaminophenAdminister acetaminophen
- 停止输血，并用新的输液管以生理盐水保持静脉通畅Stop the transfusion and keep the vein open with normal saline using new tubing
- 在触碰输液前通知血库Notify the blood bank before touching the infusion
- 减慢输血速率并在15分钟后复查Slow the transfusion rate and recheck in 15 minutes
答案: B · 停止输血，并用新的输液管以生理盐水保持静脉通畅
在任何疑似反应中，停止输血是第一步，然后是保持IV通路，然后是通知。
Stopping the transfusion comes first in any suspected reaction, then maintaining IV access, then notification.
哪种IV溶液禁用于颅内压升高的患者？Which IV solution is contraindicated for a client with increased intracranial pressure?
- Lactated Ringer's
- 3% sodium chloride
- 0.9% sodium chloride
- 0.45% sodium chloride
答案: D · 0.45% sodium chloride
低渗液体会将水移入细胞，包括脑细胞，从而加重脑水肿。3% sodium chloride是高渗的，实际上用于治疗颅内压升高，因为它将水从脑细胞中拉出。
Hypotonic fluids shift water into cells, including brain cells, worsening cerebral edema. 3% sodium chloride is hypertonic and is actually used to treat increased intracranial pressure, since it pulls water out of brain cells.
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