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。
The telemetry monitor suddenly shows a chaotic waveform resembling ventricular fibrillation, but the patient is talking and brushing their teeth. What should the nurse do first?
A 70-year-old man has a small abdominal aortic aneurysm found on screening and is placed under surveillance. Which advice is most important?
A patient with Addison's disease takes fludrocortisone as well as hydrocortisone. Why?
一名带有隧道式中心静脉导管的血液透析患者在透析开始后不久出现发热和寒战。护士应怀疑什么并如何处理?
Why is the Lund and Browder chart preferred to the rule of nines for children?
A patient on modified-release morphine for cancer pain has needed four breakthrough doses every day for several days. What should the nurse do?
Which is a first-line nursing measure to help prevent constipation in hospital?
A patient with known cirrhosis suddenly vomits large amounts of bright red blood and becomes tachycardic. What is the most likely cause?
How does the nurse start a 24-hour urine collection at 08:00?
A patient with kidney stones and fatigue has a calcium of 11.6 mg/dL (2.9 mmol/L), a high parathyroid hormone (PTH) and a low phosphate. Which condition is most likely?
某练习动脉血气显示 pH 7.65,PaCO₂ 37 mmHg (4.9 kPa),HCO₃⁻ 39 mmol/L。原发性紊乱是代谢性碱中毒。代偿到什么程度?点选你的答案。
某练习血气显示代谢性碱中毒,HCO₃⁻ 42 mmol/L。用预期 PaCO₂ = 0.7·HCO₃⁻ + 21 求预期PaCO₂。
测量这条 II 导联心电图上的QT 间期,以秒为单位。
这条 II 导联心电图显示心房与心室之间存在传导问题。这是什么节律?点击你的答案。
A patient with a valid do-not-resuscitate order (DNR; called DNACPR in the UK) stops breathing and has no pulse. What should the nurse do?
Which finding after a laparoscopic cholecystectomy is expected and needs only reassurance and comfort measures?
答案: C · Check the patient and the electrodes, as this is likely artefact
Movement, loose electrodes and muscle activity can create artefact that looks like VF. A conscious, talking patient cannot be in VF. The nurse assesses the patient and checks the leads and electrodes, then reattaches them if needed.
答案: A · Stop smoking, control BP and seek help at once for sudden back pain
Small aneurysms are usually monitored with regular ultrasound, with repair considered when they reach a threshold size or grow fast. Stopping smoking slows growth, and BP and cardiovascular risk are managed. Sudden abdominal or back pain may mean rupture and needs emergency care.
答案: A · To replace the missing aldosterone
In primary adrenal insufficiency, both cortisol and aldosterone are lacking. Hydrocortisone replaces cortisol, and fludrocortisone replaces aldosterone to keep sodium, potassium and blood pressure normal.
答案: B · 导管相关血流感染;停止透析,采集培养并上报
通过中心静脉导管开始透析时出现发热和寒战,强烈提示导管相关血流感染。应按方案停止或调整透析,采集血培养(导管和外周),通知团队并按医嘱开始静脉抗生素。检查出口处。
答案: A · It adjusts for body proportions that change with age
The Lund and Browder chart gives different percentages for the head and legs at different ages, so it is more accurate in children and is also widely used in adults.
答案: D · Report it, as the regular background dose may need review
Regular need for breakthrough doses usually means the background analgesia is inadequate. The prescriber reviews and may adjust the regular dose, while side effects such as sedation are monitored.
答案: B · Encouraging fluids, fibre and mobility
Adequate fluids, a fibre-rich diet, mobility and privacy for toileting help prevent constipation. Laxatives are added if needed, especially with opioids.
答案: C · Bleeding from ruptured oesophageal varices
Portal hypertension in cirrhosis causes oesophageal varices, which can bleed massively. This needs resuscitation, urgent endoscopy and specific drug treatment.
答案: C · Have the patient void and discard that urine, then save all urine until 08:00 the next day
The collection starts with an empty bladder, so the first void is discarded and the time recorded. All urine for the next 24 hours is saved, including a final void at the end time. If urine is discarded by mistake, the collection usually has to restart.核对依据: Urine 24-hour volume · MedlinePlus (NIH) (2025)
答案: C · Primary hyperparathyroidism
In primary hyperparathyroidism, usually from an adenoma, PTH is high despite high calcium, and phosphate is low because PTH increases its excretion. Cancer-related hypercalcemia typically has a suppressed PTH.核对依据: Parathyroid Hormone (PTH) Test · MedlinePlus (NIH) (2023); Hyperparathyroidism · MedlinePlus (NIH) (2026)
答案: 未代偿
解读血气(ROME):先看 pH:低于 7.35 为酸血症,高于 7.45 为碱血症。然后找出能解释它的指标。PaCO₂(正常 35–45 mmHg,4.7–6.0 kPa)是呼吸方面的指标,在呼吸性紊乱中与 pH 反向(Opposite)变化;HCO₃⁻(正常 22–26 mmol/L)是代谢方面的指标,与 pH 同向变化(Respiratory Opposite, Metabolic Equal,即呼吸性相反,代谢性相同)。另一个指标显示代偿情况:正常表示未代偿;沿着使 pH 回升的方向异常、而 pH 仍然异常,表示部分代偿;pH 正常而两个指标都异常,表示完全代偿。各实验室的范围略有差异;这些是练习用数值。
临床上还应检查预期代偿:代谢性碱中毒时 PaCO₂ ≈ 0.7·HCO₃⁻ + 21 = 46.3–50.3 mmHg,所以实测 37 mmHg 提示合并呼吸性碱中毒(混合性紊乱)。上面的答案是按 ROME 法的考试分类。
答案: PaCO₂ = 50.4 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: QT = 0.52 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。
粗略的规则:在正常心率下,QT 应小于 R–R 间期的一半(此处 R–R = 1.12 s)。
答案: 二度 I 型房室传导阻滞(文氏现象)
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。
答案: A · Follow the DNR order and do not start CPR
A valid DNR order means CPR is not started. The nurse keeps the patient comfortable, informs the provider and supports the family.
答案: B · Right shoulder pain from the gas used during surgery
Gas used to inflate the abdomen irritates the diaphragm and causes referred shoulder pain, which settles in a day or two. Jaundice, fever with worsening pain and signs of shock suggest complications.
ExamProblems · examproblems.com/courses/medical-surgical-nursing