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?
一名哮喘患者的峰流速为其最佳值的 40%,呼吸频率 28 次/分,不能说完整句子。SpO₂ 94%。该次发作应如何分级?
A patient with CKD is booked for a CT scan with iodinated contrast. Which measure helps protect the kidneys?
A patient with motor neurone disease reports morning headaches, poor sleep and sleepiness during the day. What do these symptoms suggest?
Why is the time a surgical limb tourniquet is inflated carefully recorded?
An immobile patient on opioids drinks very little. Which laxative choice is least appropriate?
A patient has a fentanyl patch for chronic pain. Which advice is correct?
A patient with lung cancer develops swelling of the face and arms, distended neck veins and breathlessness that is worse lying down. What should be suspected?
A patient with diabetes is found unconscious with a blood glucose of 38 mg/dL (2.1 mmol/L). Which treatment is appropriate?
一名转移性乳腺癌患者钙为 13.2 mg/dL(3.3 mmol/L),意识模糊并便秘。护士预期会首先开始哪种处方治疗?
练习数值:Na⁺ 133 mmol/L,葡萄糖 6.2 mmol/L,尿素 25 mmol/L。计算血清渗透压 Osm = 2·Na⁺ + 葡萄糖 + 尿素,取最接近的整数。
某练习血气显示呼吸性酸中毒:pH 7.18,PaCO₂ 78 mmHg (10.4 kPa),HCO₃⁻ 28 mmol/L。利用规则“HCO₃⁻ 每 10 mmHg 升高 1 mmol/L(急性)或 3.5 mmol/L(慢性)”进行分类。点选你的答案。
解读这条 II 导联心律条带。这是什么节律?点击你的答案。
依次按五个步骤解读这条 II 导联心电图:心率、节律、P 波、PR 间期、QRS 时限。你在哪一步发现第一个异常?点击它。
在 START 分诊中,一名不能行走的成人每分钟呼吸 36 次。该伤员被归入哪一类?
Which patient is the best choice for the room closest to the nurses’ station?
答案: B · 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: D · 急性重度哮喘
在常用指南(如 BTS/SIGN)中,峰流速为最佳值的 33–50%、呼吸频率 25 次/分或以上、心率 110 次/分或以上,或不能说完整句子,提示急性重度哮喘。危及生命的特征包括峰流速低于 33%、SpO₂ 低于 92%、“沉默肺”、发绀、衰竭或意识混乱;濒死性哮喘是指 PaCO₂ 升高或需要通气。
答案: C · Good hydration around the scan, often with IV fluids
Iodinated contrast can contribute to AKI in at-risk patients. Good hydration, using the lowest dose needed, avoiding nephrotoxic drugs and checking kidney function afterwards help reduce the risk.
答案: D · Weak breathing at night, so a review for ventilation support
Weak respiratory muscles cause nocturnal hypoventilation and a rise in CO2, leading to morning headaches, disturbed sleep and daytime drowsiness. Non-invasive ventilation can improve symptoms and survival, in line with the patient's wishes.
答案: B · Long inflation can cause nerve and muscle damage
A tourniquet creates a bloodless field but causes limb ischaemia. Inflation time and pressure are recorded and the surgeon is told at set intervals, as long inflation can damage nerves and muscle.
答案: A · A bulk-forming laxative used on its own
Bulk-forming laxatives need good fluid intake and mobility and can worsen constipation or cause obstruction without them. They do not counter the effect of opioids on gut movement, so stimulant or osmotic laxatives are preferred.
答案: A · Avoid heat sources such as hot water bottles over the patch
Heat increases absorption of fentanyl through the skin and can cause overdose. Old patches are removed and folded before disposal, and patches should not be cut unless the product allows it.
答案: A · Superior vena cava obstruction
Superior vena cava obstruction prevents venous drainage from the head and arms. It is an oncological emergency; patients are positioned upright and need urgent specialist treatment.
答案: A · Glucagon by injection, or IV dextrose as prescribed
A patient who cannot swallow safely must not receive anything by mouth because of the risk of aspiration. Glucagon (injected or intranasal) or IV dextrose raises the glucose; once awake and able to swallow, the patient is given oral carbohydrate and a snack.核对依据: Hypoglycemia · MedlinePlus (NIH); Low blood sugar · MedlinePlus (NIH) (2026)
答案: D · 静脉输注 0.9% 氯化钠
高钙血症导致大量排尿和脱水。静脉生理盐水可恢复血容量并帮助肾脏排钙;随后通常使用双膦酸盐。噻嗪类药物减少钙的排泄,而制动会使骨释放钙。核对依据: Hypercalcemia · MedlinePlus (NIH) (2026)
答案: Osm = 297 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: 急性
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: 窦性心律不齐
节律标准(II 导联):窦性心律每个 QRS 之前都有直立的 P 波,PR 恒定为 0.12–0.20 s,QRS 狭窄:60–100 次/分为正常窦性心律,低于 60 为窦性心动过缓,高于 100 为窦性心动过速。心房颤动:无 P 波,基线呈颤动,R–R 绝对不规则。心房扑动:约 250–350 次/分的锯齿状扑动波,伴固定的传导比例,如 2:1 或 4:1。一度房室传导阻滞:窦性心律,PR 恒定且大于 0.20 s。交界性心律:窄 QRS,40–60 次/分,P 波缺失或倒置(PR 低于 0.12 s,或 P 波在 QRS 之后)。室性早搏(PVC)是提前出现的宽大(0.12 s 或以上)、形态怪异的 QRS,没有 P 波,T 波方向相反,通常有完全性代偿间歇;二联律是指每隔一个搏动就有一个室性早搏。
答案: 节律
每条心电图的五个步骤:1. 心率(300 法或 1500 法;若不规则则用 6 秒法);2. 节律:R–R 间期是否相等;3. P 波:是否存在、在 II 导联直立、每个 QRS 之前各有一个且形态一致;4. PR 间期:0.12–0.20 s 且恒定;5. QRS 时限:低于 0.12 s。五个步骤做完之后才命名节律。正常窦性心律五项全部符合:60–100 次/分,规则,每个 QRS 之前有直立 P 波,PR 0.12–0.20 s,QRS 低于 0.12 s。
答案: A · 红色(立即)
在 START 中,呼吸频率超过 30 次/分意味着伤员被标为立即(红色)。30 次或以下则继续进行灌注和意识状态检查。
答案: C · A confused older adult at high risk of falls
A confused patient at high risk of falls benefits from being close to staff, so they can be observed and helped quickly. The other patients are stable and independent.
ExamProblems · examproblems.com/courses/medical-surgical-nursing