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。
How is orthostatic (postural) hypotension usually assessed?
The monitor shows a regular broad-complex tachycardia at 180/min. The patient is alert with BP 126/78 mmHg and no chest pain. What is the most appropriate plan?
Which side effects are common with oxybutynin for an overactive bladder?
A man who takes tamsulosin for BPH is listed for cataract surgery. Which statement is correct?
What is anticipatory nausea in chemotherapy?
After surgery, a patient says they have "no pain" but grimaces, breathes shallowly and refuses to move or cough. What should the nurse do?
Why are people with diabetes advised to have regular eye screening?
开始输血后不久,患者出现气短、喘鸣、低血压和面部肿胀。护士首先应该做什么?
A healthy patient's result is slightly outside the laboratory reference range, and all other results are normal. Which statement best explains why this can happen?
A patient on high-dose dexamethasone has a white cell count of 15 × 10³/µL, mostly mature neutrophils with no bands. They have no fever and no signs of infection. What is the most likely explanation?
某练习动脉血气显示 pH 7.44,PaCO₂ 53 mmHg (7.1 kPa),HCO₃⁻ 35 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酸中毒:pH 7.22,PaCO₂ 43 mmHg (5.7 kPa),HCO₃⁻ 17 mmol/L。把实测的PaCO₂与温特公式比较。点选你的解读。
解读这条 II 导联心律条带。这是什么节律?点击你的答案。
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 at 35 weeks of pregnancy with high blood pressure calls the clinic. Which symptom needs urgent assessment?
A patient at 36 weeks of pregnancy has sudden severe abdominal pain, a hard, board-like uterus and dark vaginal bleeding. What should the nurse suspect?
答案: C · BP lying after rest, then again after 1 and 3 minutes standing
Blood pressure is measured after the patient has been lying for about 5 minutes, then after 1 and 3 minutes of standing. A fall in systolic pressure of 20 mmHg or more, or diastolic of 10 mmHg or more, indicates orthostatic hypotension. Symptoms such as dizziness are recorded too.
答案: B · Record a 12-lead ECG, call senior help and anticipate an antiarrhythmic
A broad-complex tachycardia is treated as ventricular tachycardia until proven otherwise. With a pulse and no adverse features (shock, syncope, chest pain or heart failure), a 12-lead ECG, electrolyte correction and drug treatment such as amiodarone are used, with expert help. Unstable patients need synchronised cardioversion; pulseless VT is defibrillated.
答案: D · Dry mouth and constipation
Oxybutynin blocks muscarinic receptors, causing dry mouth, constipation, blurred vision, urinary retention and, especially in older adults, confusion. Newer agents may have fewer effects on the brain.
答案: D · The eye surgeon must be told, as it can cause floppy iris during surgery
Tamsulosin blocks alpha-1A receptors in the iris dilator muscle as well as in the prostate, which can cause intraoperative floppy iris syndrome during cataract surgery. The effect can persist after the drug is stopped, so the surgeon must know in advance to plan the operation. Whether to pause it is a decision for the team.
答案: A · Nausea triggered by reminders of treatment before it is given
Anticipatory nausea is a conditioned response after previous poorly controlled nausea, triggered by sights or smells linked to treatment. Good antiemetic control from the first cycle helps prevent it; relaxation techniques and anxiolytics may help.
答案: B · Explore their beliefs and explain how analgesia aids recovery
Patients may under-report pain because of beliefs, fear of addiction or not wanting to bother staff. Exploring these concerns and explaining that good analgesia helps breathing and mobility supports a shared plan.
答案: D · To detect diabetic retinopathy early, before sight is lost
Diabetic retinopathy often has no symptoms until it is advanced. Screening allows early treatment that can prevent blindness.
答案: C · 停止输血,保留静脉通路,并紧急呼救
严重输血反应(包括过敏性休克)需要立即停止输血,保留静脉通路,按 ABCDE 方法处理,并用肌注肾上腺素治疗过敏性休克。
答案: B · Ranges cover about 95% of healthy people, so some fall outside
A reference range is usually the central 95% of results from a healthy population, so about 1 in 20 healthy people will have a value just outside it. The result is interpreted with the clinical picture and previous values, and repeated if needed.核对依据: How to Understand Your Lab Results · MedlinePlus (NIH) (2025)
答案: D · A steroid effect that moves neutrophils into the circulating blood
Corticosteroids raise the neutrophil count by releasing marginated neutrophils and slowing their exit from the blood, usually without a left shift. The nurse still assesses carefully, because steroids can also hide the usual signs of infection.
答案: 完全代偿
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 = 43.5–47.5 mmHg,所以实测 53 mmHg 提示合并呼吸性酸中毒(混合性紊乱)。上面的答案是按 ROME 法的考试分类。
答案: 合并呼吸性酸中毒
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: 窦性心律伴窦性停搏
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。 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)。
答案: 二度 II 型房室传导阻滞
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。
II 型和三度阻滞可能突然进展,所以教科书将它们列为比 I 型更严重。
答案: A · A severe headache with blurred vision
A severe headache and visual changes can be signs of severe pre-eclampsia and a risk of eclampsia. Mild ankle swelling, backache and frequent urination are common in late pregnancy.
答案: B · Placental abruption, which is an emergency
Painful bleeding with a rigid, tender uterus suggests placental abruption, where the placenta separates early. Mother and baby are at risk, so urgent escalation and monitoring are needed.
ExamProblems · examproblems.com/courses/medical-surgical-nursing