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 is on a short course of oral prednisolone for an asthma exacerbation. Which effect should the nurse monitor for?
A patient regains a pulse after a ventricular fibrillation arrest that was probably caused by a heart attack. Which investigation is most urgent?
A patient with atrial fibrillation has had an ischaemic stroke. Which long-term medicine type most reduces the risk of another stroke?
A patient on carbamazepine is admitted confused, with a sodium of 121 mmol/L. Which explanation is most likely?
Why is the Lund and Browder chart preferred to the rule of nines for children?
A nurse teaches a patient with GORD. Which statement shows a need for further teaching?
A patient with pneumonia is breathless and coughing up thick sputum. Which nursing measure helps most with breathing?
一名全髋关节置换术后的患者突然出现剧烈髋部疼痛,下肢缩短并发生旋转。最可能的并发症是什么?
实验室打电话到病房报告钾的危急值 6.9 mEq/L。护士应怎么做?
The nurse teaches a patient who is starting warfarin. Which statement shows a need for further teaching?
某练习动脉血气显示 pH 7.60,PaCO₂ 38 mmHg (5.1 kPa),HCO₃⁻ 36 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。
练习数值:Na⁺ 144,Cl⁻ 115,HCO₃⁻ 12 mmol/L,白蛋白 16 g/L。求经白蛋白校正的阴离子间隙 AGc = AG + 0.25·(40 − 白蛋白)。
测量这条 II 导联心电图上的QT 间期,以秒为单位。
这条 II 导联心电图显示二度房室传导阻滞 I 型(文氏现象)。测量未下传 P 波之前最后一个下传搏动的 PR 间期(即最长的 PR),以秒为单位。
A nursing assistant offers to suction a patient’s new tracheostomy. Which response from the RN is best?
A patient arrives one hour after the start of stroke symptoms. Which step must happen before a thrombolytic drug can be given?
答案: B · Raised blood glucose
Corticosteroids raise blood glucose, which matters especially in diabetes. Short courses can also cause mood changes, insomnia, indigestion and fluid retention. Long-term use adds osteoporosis, adrenal suppression and infection risk.
答案: A · A 12-lead ECG
After return of spontaneous circulation, a 12-lead ECG looks for STEMI, which needs urgent coronary angiography and PCI. Post-resuscitation care also aims for normal oxygen and CO₂ levels, blood pressure support, glucose control and avoiding fever.
答案: C · An oral anticoagulant
In AF the main cause of stroke is a clot from the left atrium. Oral anticoagulants such as a DOAC or warfarin prevent this far better than antiplatelets. The start date after a stroke depends on its size and bleeding risk.
答案: B · Carbamazepine can cause hyponatraemia through an SIADH-like effect
Carbamazepine (and oxcarbazepine) can increase the effect of ADH, leading to water retention and hyponatraemia. Severe hyponatraemia causes confusion and seizures. The drug and sodium need urgent medical review.
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: C · "Peppermint tea after dinner will settle my reflux."
Peppermint can relax the lower oesophageal sphincter and may worsen reflux. Weight loss, stopping smoking and avoiding personal triggers are standard lifestyle measures.
答案: A · Sitting the patient upright and supporting them to clear secretions
An upright position improves lung expansion, and adequate fluids, deep breathing and coughing help clear sputum. Oxygen is given to target saturations if needed.
答案: C · 假体脱位
关节置换术后髋关节脱位会引起突发疼痛、下肢缩短和旋转。需要紧急评估和复位;应教会患者活动注意事项。
答案: B · 复述该数值,评估患者并通知医疗人员
复述口头报告的结果可防止差错。危急值应毫不延迟地报告给医疗人员,护士应评估患者,包括心律。可能需要重新采样,但不得延误反应。
答案: C · "If I miss a dose, I will take two tablets the next day"
Doubling a missed warfarin dose can raise the INR and cause bleeding; the patient should follow the prescriber's instructions, usually taking the missed dose the same day or skipping it. A steady vitamin K intake, regular INR checks and telling other providers are correct.核对依据: Warfarin (drug information) · 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 = 44.2–48.2 mmHg,所以实测 38 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: AGc = 23 mmol/L
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。
校正后高于约 12:阴离子间隙升高。
答案: QT = 0.34 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 = 0.80 s)。
答案: 最长的 PR = 0.38 s
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。
PR 最大的增幅出现在一组的第一个和第二个搏动之间;之后的增幅较小,这就是暂停之前 R–R 间期缩短的原因。
答案: C · “Suctioning a new tracheostomy is my task; I will do it myself.”
Care of a new tracheostomy, including suctioning, involves airway risk and assessment, so the RN keeps it. Leaving it to the family or the next shift is unsafe.
答案: A · A brain scan to rule out bleeding
Thrombolytics dissolve clots and would worsen a hemorrhagic stroke. A brain CT (or MRI) is needed first to rule out bleeding, and it must be done quickly.
ExamProblems · examproblems.com/courses/medical-surgical-nursing