内外科护理:心血管与呼吸
方法
- 说出问题所在:泵衰竭、动脉阻塞、节律、血栓、气道狭窄、感染或设备问题。
- 先检查危险征象:低氧、低血压、胸痛、新出现的意识模糊、冰冷无脉搏的肢体。
- 让氧疗与患者相匹配:大多数人为 94–98%,有 CO₂ 潴留风险者为 88–92%。
- 把每种药物与其检测和风险联系起来:华法林与 INR,肝素与 aPTT 和血小板,利尿剂与血钾。
- 选择安全的第一步措施,然后升级处理并重新评估。
公式表、每个专题的关键方法步骤和 16 道练习题,完整解答附在最后。
A patient takes both digoxin and furosemide. Why does the nurse watch the potassium level closely?
A patient on an unfractionated heparin infusion has a nosebleed that will not stop, and the aPTT is far above the target range. What is the most appropriate action?
甲状腺手术一周后,一名患者的声音仍然嘶哑无力。最可能的并发症是什么?
血液透析期间,一名患者血压降至 80/50 mmHg,感到头晕恶心。最恰当的首要护理措施是什么?
Why is it important to prevent perioperative hypothermia?
Two hours after a meal, a patient who had a gastrectomy becomes shaky, sweaty and confused. What is the most likely cause and first action?
A patient has a continuous stream of bubbles in the water seal chamber of their chest drain. What does this most likely indicate?
A patient is admitted with suspected meningococcal disease. Which infection control measure is usually needed?
A patient with iron-deficiency anemia started oral iron. Which result is usually the earliest sign that treatment is working?
A patient who had pituitary surgery has fatigue and cold intolerance. The free T4 is low and the TSH is low. What does this pattern suggest?
某练习血气显示代谢性酸中毒,HCO₃⁻ 6 mmol/L。用温特公式求预期PaCO₂(范围的中心),单位 mmHg。
练习数值:Na⁺ 145,Cl⁻ 91,HCO₃⁻ 14 mmol/L。使用 AG = Na⁺ − (Cl⁻ + HCO₃⁻) 计算 Δ 比值 (AG − 12)/(24 − HCO₃⁻)。保留两位小数。
这条 II 导联心电图条带显示窦性心律伴一次停顿。测量 停顿,即跨越停顿的 R–R 间期,单位为秒。
识别这条 II 导联心电图上的节律。点击你的答案。
Which patient should the RN see first after receiving a report from the night nurse?
An older adult with type 2 diabetes is confused and very dehydrated. The glucose is 900 mg/dL (50 mmol/L), and blood and urine show no significant ketones. What is the most likely problem?
答案: C · Low potassium increases the risk of digoxin toxicity
Digoxin binds to the Na⁺/K⁺-ATPase pump at the site potassium normally uses. When potassium is low, more digoxin binds, so toxicity and arrhythmias become more likely. Loop diuretics commonly cause hypokalaemia, so the combination needs monitoring.
答案: C · Stop the infusion, inform the prescriber and anticipate protamine
With bleeding and a high aPTT, the heparin infusion is stopped at once and the prescriber informed. Because heparin's effect wears off within hours, stopping is often enough, but protamine sulfate can reverse it. Vitamin K reverses warfarin, not heparin.
答案: A · 喉返神经损伤
喉返神经紧邻甲状腺走行,支配大部分喉肌。损伤会引起声音嘶哑;双侧损伤可引起喘鸣和气道梗阻。插管引起的轻度声音嘶哑通常几天内好转。甲状旁腺损伤引起低钙血症,伴麻木和痉挛。
答案: C · 让患者平躺,减少超滤,并寻求帮助
透析中低血压很常见。调整体位、减少或暂停超滤,并按方案给予少量生理盐水推注,通常可恢复血压。对易发生低血压的患者,降压药常按医嘱在透析前暂停。
答案: B · It increases bleeding, wound infection and heart complications
Even mild hypothermia impairs clotting, increases surgical site infection and cardiac events, and causes shivering and discomfort. Forced-air warming, warmed fluids and covering the patient help prevent it.
答案: B · Late dumping with low blood glucose; check capillary glucose
In late dumping, rapid sugar absorption triggers a large insulin release, followed by reactive hypoglycaemia 1–3 hours after eating. The nurse checks glucose and treats hypoglycaemia; dietary changes help prevent it.
答案: D · An air leak, from the lung or from the drainage system
Bubbling with breathing in a drain for pneumothorax shows air is leaving the pleural space. Continuous bubbling can also mean a leak in the connections, so the system is checked and the finding reported.
答案: C · Droplet precautions until 24 hours of effective antibiotics have been given
Neisseria meningitidis spreads through droplets and close contact. Droplet precautions are used until 24 hours of effective antibiotics, and public health arranges prophylaxis for close contacts.
答案: A · A rise in the reticulocyte count
Once iron is available, the marrow releases more young red cells, so the reticulocyte count rises within about 1–2 weeks. The hemoglobin rises more slowly over weeks, and iron stores take months to refill.核对依据: Reticulocyte Count · MedlinePlus (NIH) (2024)
答案: C · Secondary (central) hypothyroidism from pituitary failure
In primary hypothyroidism, a low T4 causes a high TSH. A low T4 with a low or inappropriately normal TSH means the pituitary (or hypothalamus) is not producing enough TSH, so the TSH cannot be used alone to monitor treatment.核对依据: Thyroxine (T4) Test · MedlinePlus (NIH) (2024); Hypothyroidism · MedlinePlus (NIH) (2024)
答案: PaCO₂ = 17 mmHg
预期代偿:代谢性酸中毒时,温特公式预测 PaCO₂ = 1.5·HCO₃⁻ + 8 ± 2 mmHg;实测值高于该范围提示合并呼吸性酸中毒,低于该范围提示合并呼吸性碱中毒。阴离子间隙 AG = Na⁺ − (Cl⁻ + HCO₃⁻),正常约为 8–12 mmol/L,用于区分高阴离子间隙与正常阴离子间隙代谢性酸中毒;低白蛋白会掩盖升高的间隙(白蛋白低于 4.0 的部分,每 g/dL 加 2.5)。Δ 比值 (AG − 12)/(24 − HCO₃⁻) 约在 0.8 到 2 之间符合单纯高间隙酸中毒(有些教材用 1 代替 0.8),低于此范围提示合并正常间隙酸中毒,高于 2 提示合并代谢性碱中毒。
答案: Δ 比值 = 2.8
预期代偿:代谢性酸中毒时,温特公式预测 PaCO₂ = 1.5·HCO₃⁻ + 8 ± 2 mmHg;实测值高于该范围提示合并呼吸性酸中毒,低于该范围提示合并呼吸性碱中毒。阴离子间隙 AG = Na⁺ − (Cl⁻ + HCO₃⁻),正常约为 8–12 mmol/L,用于区分高阴离子间隙与正常阴离子间隙代谢性酸中毒;低白蛋白会掩盖升高的间隙(白蛋白低于 4.0 的部分,每 g/dL 加 2.5)。Δ 比值 (AG − 12)/(24 − HCO₃⁻) 约在 0.8 到 2 之间符合单纯高间隙酸中毒(有些教材用 1 代替 0.8),低于此范围提示合并正常间隙酸中毒,高于 2 提示合并代谢性碱中毒。
高于 2:合并代谢性碱中毒。
答案: 停顿 = 1.8 s
窄 QRS 心动过速与停顿:室上性心动过速(SVT)是规则的心动过速,约 150–250 次/分钟,QRS 波群较窄;P 波通常看不到,因为它们隐藏在 QRS 波群或 T 波中。成人静息时的窦性心动过速通常低于约 150 次/分钟,且每个 QRS 前都有可见的 P 波;伴 2:1 传导的心房扑动常在约 150 次/分钟,并显示锯齿波。窦性停搏是指窦房结暂时停止发放冲动:出现既无 P 波也无 QRS 的停顿,其长度不是 P–P 周期的整数倍(恰好两个或三个周期的停顿则提示窦房传导阻滞)。
停顿中没有出现 P 波,且停顿不是 P–P 周期的整数倍:窦性停搏。恰好两个或三个周期的停顿则提示窦房传导阻滞。
答案: 室性自搏心律
更多室性心律:尖端扭转型室性心动过速是一种多形性室性心动过速,通常为 150–250 次/分钟,其增宽的波群高度不断变化并围绕基线扭转,先向上几个心搏,再向下。教科书将其与 QT 间期延长联系起来,复苏指南中针对它推荐的药物是硫酸镁。室性自搏心律是一种心室逸搏心律:规则、QRS 增宽(0.12 s 或以上)、无 P 波,频率 20–40 次/分钟(加速性室性自搏心律为 40–100 次/分钟)。单形性室速的增宽波群完全相同,频率超过 100 次/分钟。室颤则是混乱的,没有任何重复的波群。
室性自搏心律是一种逸搏心律:由于上方的起搏点失灵,心室接管了节律。
答案: A · Day 1 after bowel surgery, new chest pain and heart rate 110/min
New chest pain and tachycardia after surgery could be a myocardial infarction or pulmonary embolism. This patient needs immediate assessment; the others have routine needs.
答案: D · Hyperosmolar hyperglycemic state
Hyperosmolar hyperglycemic state occurs mainly in type 2 diabetes, with extreme glucose, severe dehydration and little or no ketosis. Treatment starts with IV fluids, as in DKA.
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