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 with heart failure starts dapagliflozin, an SGLT2 inhibitor. Which teaching is most relevant?
A patient with severe aortic stenosis is prescribed glyceryl trinitrate (nitroglycerin) for chest pain. Why should the nurse use particular caution?
How does bladder training help urge incontinence?
A patient on warfarin starts levothyroxine for hypothyroidism. What should the nurse expect to monitor more closely?
小肠梗阻和大肠梗阻的主要临床区别是什么?
一名使用阿片类药物 PCA 的患者经面罩吸氧。SpO₂ 97%,呼吸频率 11 次/分,但现在很难唤醒。护士应得出什么结论?
Which is a recognised risk factor for postoperative nausea and vomiting?
一名老年患者夜间突然出现意识混乱,注意力时好时坏。首先应寻找什么原因?
A patient with hyperkalemia received IV regular insulin with dextrose. Which result must the nurse monitor closely over the next hours?
A patient on clozapine reports a sore throat and fever. The ANC is 400/µL (0.4 × 10⁹/L). What should the nurse do?
练习数值:Na⁺ 129 mmol/L,葡萄糖 32.8 mmol/L,尿素 12.4 mmol/L。计算血清渗透压 Osm = 2·Na⁺ + 葡萄糖 + 尿素,取最接近的整数。
某练习血气显示代谢性碱中毒,HCO₃⁻ 46 mmol/L。用预期 PaCO₂ = 0.7·HCO₃⁻ + 21 求预期PaCO₂。
在这条规则的 II 导联心电图上测量 QT 间期和 R–R 间期,然后用 Bazett 公式 QTc = QT/√RR(均以秒计)计算经心率校正的QTc。答案以秒表示,保留三位小数。
这条 II 导联心电图显示房室传导阻滞,所以心房和心室以不同的频率搏动。测量 P–P 间期,求出心房率(单位:次/分,1500 法,取整数)。
对于采取防跌倒措施的患者,护士应将哪项任务委派给护理助理?
A patient taking an SSRI is also given tramadol. A few hours later the patient is agitated, sweating and has a fever, jerking muscles and brisk reflexes. What is the most likely cause?
答案: D · Keep the genital area clean, as fungal infections are more common
SGLT2 inhibitors increase glucose loss in the urine, raising the risk of genital thrush and urinary infections. They also cause mild diuresis, and in people with diabetes there is a rare risk of ketoacidosis, so they are paused during acute illness as advised. They improve outcomes in heart failure.
答案: B · Vasodilators can cause a severe fall in BP with a fixed outflow obstruction
In severe aortic stenosis, cardiac output is fixed by the narrow valve. Vasodilators lower preload and afterload, and the heart cannot compensate, so the blood pressure can fall sharply and cause syncope. They are used with care and close monitoring.
答案: A · The time between voids is slowly increased
In bladder training, the patient follows a schedule and gradually lengthens the time between voids while using urge-suppression techniques. Over weeks, bladder capacity and control improve. Very low fluid intake makes urine concentrated and irritating.
答案: C · The INR, because it may rise
As thyroid function returns to normal, clotting factors are broken down faster, which increases the effect of warfarin. The INR is checked more often and the warfarin dose may need to be reduced.
答案: A · 小肠:呕吐早,腹胀较轻;大肠:呕吐晚,腹胀明显
在近端小肠梗阻中,呕吐出现早且明显,腹胀较轻。在大肠梗阻中,腹胀明显,便秘出现早,呕吐较晚(可为粪样)。影像学检查可确认梗阻的水平和原因。
答案: A · 很可能是阿片类药物中毒;氧气可能掩盖了通气不足
补充氧气可使 SpO₂ 保持正常,而 CO₂ 却因通气不足而升高。镇静加深是阿片类药物中毒的早期征象。护士应停止 PCA,刺激患者,呼叫援助并遵循纳洛酮方案,密切监测呼吸频率、深度和镇静程度。
答案: D · Use of opioids after surgery
Known risk factors include opioids, female sex, being a non-smoker, previous PONV or motion sickness and longer general anaesthetics. High-risk patients may be given preventive antiemetics.
答案: B · 由感染或药物等潜在问题引起的谵妄
谵妄在数小时到数天内发生,并呈波动性。常见原因有感染、药物、脱水、疼痛、便秘和尿潴留。痴呆则是缓慢发展的。
答案: D · Blood glucose, because hypoglycemia can occur
Insulin shifts potassium into cells but also lowers glucose, and hypoglycemia can occur hours later, especially in kidney failure. Glucose is checked frequently, and potassium is rechecked, as the effect lasts only a few hours.核对依据: High potassium level · MedlinePlus (NIH) (2025)
答案: B · Hold the clozapine and report the result at once
An ANC below 500/µL is severe neutropenia, and with fever and sore throat it suggests a serious infection. Clozapine is held, the provider is told immediately, and infection is assessed and treated. A nurse never changes a dose without a prescription.
答案: Osm = 303 mOsm/kg
衍生数值:计算所得的血清渗透压为 2·Na⁺ + 葡萄糖 + 尿素,各值均以 mmol/L 计(葡萄糖和 BUN 以 mg/dL 计时为 2·Na⁺ + 葡萄糖/18 + BUN/2.8);正常约为 275–295 mOsm/kg。P/F 比值是 PaO₂ 除以以小数表示的 FiO₂。海平面的肺泡氧分压为 PAO₂ = FiO₂·(760 − 47) − PaCO₂/0.8 mmHg,A–a 梯度为 PAO₂ − PaO₂。
答案: PaCO₂ = 53.2 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。
升高是有限度的:仅靠代偿,PaCO₂ 很少超过约 55 mmHg。
答案: QTc = 0.413 s
QT 与 QTc:QT 间期从 QRS 波群起点到 T 波终点。它随心率加快而缩短,因此要用以秒为单位的 R–R 间期按心率校正:Bazett QTc = QT/√RR,Fridericia QTc = QT/∛RR。多数教科书使用 Bazett 公式;它在心率快时校正过度,此时宜用 Fridericia。各参考标准的界限不同:QTc 男性高于约 0.45 s、女性高于约 0.46 s 通常称为延长,高于 0.50 s 称为明显延长。
在通常上限之内(男性约 0.45 s,女性约 0.46 s)。(413 ms)
答案: 心房率 = 79 bpm
房室传导阻滞:逐个标出 P 波,检查哪些 P 波后面跟着 QRS。一度:每个 P 波都下传,PR 恒定且大于 0.20 s。二度 I 型(Mobitz I,文氏现象):PR 逐搏延长,直到一个 P 波未下传,然后周期重新开始(成组搏动)。二度 II 型(Mobitz II):下传搏动的 PR 保持恒定,P 波突然不下传;QRS 常增宽。三度(完全性)阻滞:P 波和 QRS 波群各自规则但互相独立,PR 随机变化,心房率快于逸搏率(交界性逸搏 40–60 次/分,QRS 窄;室性逸搏 20–40 次/分,QRS 宽)。2:1 阻滞仅凭一份条带无法判断是 I 型还是 II 型。
二度 II 型:每 3 个 QRS 波群对应 4 个 P 波,PR 恒定。
答案: D · 按计划每 2 小时协助患者上厕所
定时如厕巡视是遵循护理计划的常规任务。跌倒风险评分、决定干预措施和教育都需要护理判断。
答案: B · Serotonin syndrome
SSRIs and tramadol both raise serotonin. Agitation, fever, clonus and hyperreflexia that start quickly suggest serotonin syndrome; neuroleptic malignant syndrome follows antipsychotics and causes rigid muscles with slow reflexes.
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