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 in cardiac rehabilitation asks how hard to exercise. Which simple guide is commonly taught?
Twelve hours after a coronary stent, a patient has sudden severe chest pain again with new ST elevation in the same leads. What is the most likely cause?
Which complication is a particular risk in nephrotic syndrome?
A patient on insulin has worsening chronic kidney disease and is having more hypos. What is the best explanation?
什么是麻痹性肠梗阻?
A patient's platelet count is 18 × 109/L (18,000/µL). Which order should the nurse question?
Which advice should be given to a patient with a new permanent pacemaker?
A patient with known cirrhosis suddenly vomits large amounts of bright red blood and becomes tachycardic. What is the most likely cause?
A patient taking furosemide has a potassium of 3.3 mEq/L and is told to eat more potassium-rich foods. Which snack is the best choice?
A patient on long-term amiodarone has fatigue and weight gain. TSH is 11 mIU/L and the free T4 is low. What is the most likely explanation?
练习数值:Na⁺ 137 mmol/L,葡萄糖 14.6 mmol/L,尿素 12.8 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 7.31,PaCO₂ 72 mmHg (9.6 kPa),HCO₃⁻ 35 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。
这位患者装有起搏器。请解读这条 II 导联心电图条带。点击你的答案。
A patient is receiving opioids after surgery. Which finding usually comes before opioid-induced respiratory depression?
一名心力衰竭患者气短,双肺有湿啰音。哪种行动顺序是正确的?
答案: C · Exercise so they are a little breathless but can still talk
Moderate-intensity exercise makes the patient slightly breathless but able to hold a conversation. Programmes start gently and progress. Patients stop and seek help if they get chest pain, severe breathlessness or dizziness.
答案: A · Acute stent thrombosis
Acute stent thrombosis presents with recurrent ischaemic pain and ST elevation, and needs emergency return to the catheter laboratory. Missed antiplatelet doses are a major risk factor, which is why dual antiplatelet adherence is emphasised.
答案: A · Venous thrombosis
In nephrotic syndrome, anticoagulant proteins such as antithrombin are lost, and clotting factors made by the liver rise, so venous thrombosis is more likely. Infection and high cholesterol are other complications.
答案: C · The kidneys clear less insulin, so it lasts longer
The kidneys clear a large share of insulin. As kidney function falls, insulin stays in the blood longer and some oral agents build up, so hypos increase. Insulin doses often need to be reduced.
答案: D · 没有物理性阻塞,但肠蠕动丧失
麻痹性肠梗阻是蠕动停止的功能性梗阻,常见于腹部手术后、使用阿片类药物、感染或电解质紊乱(尤其是低钾)。肠鸣音减弱或消失。
答案: C · An intramuscular injection
IM injections can cause haematomas in severe thrombocytopenia. Rectal procedures, NSAIDs and aspirin are also avoided. The nurse checks with the prescriber and the oral or IV route is used where possible.
答案: A · Tell staff about the pacemaker before any MRI scan or procedure
Patients carry a device card and tell staff before MRI, surgery with diathermy or similar procedures. Arm movement on the pacemaker side is limited only for a short period after insertion.
答案: D · 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 · Dried apricots
Dried fruits such as apricots, raisins and prunes are rich in potassium, as are bananas, oranges, potatoes, beans and tomatoes. Refined grain products such as white bread and crackers are low in potassium.核对依据: Potassium in diet · MedlinePlus (NIH) (2026)
答案: D · Amiodarone-induced hypothyroidism
Amiodarone is rich in iodine and can cause either hypothyroidism or hyperthyroidism. A high TSH with a low free T4 shows primary hypothyroidism, so thyroid function is monitored before and during therapy; liver tests are monitored too.核对依据: Hypothyroidism · MedlinePlus (NIH) (2024)
答案: Osm = 301 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: 慢性
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: 室上性心动过速(SVT)
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: 心室起搏心律
起搏心律:起搏器脉冲表现为一条细而垂直的起搏钉样信号。心室钉样信号之后的 QRS 是增宽的(0.12 s 或以上),因为冲动是从导线经心肌传播,而不是经传导系统;右心室起搏时,在 II 导联上通常以负向为主。P 波之前的钉样信号表示心房起搏;双腔(房室)起搏器则表现为心房钉样信号加 P 波,再经过程控的房室延迟,出现心室钉样信号和增宽的 QRS。夺获是指每个钉样信号之后都跟着一次除极。夺获失败是指钉样信号之后没有 P 波或 QRS;感知不良(钉样信号无视患者自己的心搏)和起搏不良(该出现钉样信号时没有)是另外两种典型的故障。
起搏产生的 QRS 本来就是增宽的;不要称它为束支传导阻滞或室性心律。
答案: C · Increasing sleepiness that is hard to rouse
Sedation usually increases before breathing slows. Regular sedation checks let the nurse hold the opioid and act before respiratory depression occurs.
答案: D · 坐起,按医嘱给氧,然后联系医疗人员
坐直可减少回心血量并缓解呼吸,氧气治疗缺氧。然后联系医疗人员并准备利尿剂。平躺或静脉补液会加重肺淤血。
ExamProblems · examproblems.com/courses/medical-surgical-nursing