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 on theophylline develops nausea, vomiting, a fast heart rate and restlessness. What should the nurse suspect?
早晨给地高辛之前,患者的心尖脉搏为 54 次/分,并感到恶心。护士应怎么做?
一名服用卡比马唑治疗甲状腺功能亢进的患者主诉咽痛和发热。护士应怎么做?
An adult stares blankly for about a minute, smacks their lips and fumbles with their clothes. Afterwards they are confused for ten minutes and remember nothing. Which seizure type fits best?
什么是肿瘤溶解综合征?
In recovery, an awake and anxious patient cannot lift their head, and their breaths are shallow and weak. What is the most likely cause?
Which examination findings suggest a large pleural effusion on one side?
Why are liquid medicines for nasogastric tubes drawn up in dedicated enteral (oral) syringes rather than IV syringes?
A 55-year-old has a positive fecal immunochemical test (FIT) during routine screening. What is the usual next step?
一名酒精使用障碍的患者尽管补钾两天,钾仍为 3.0 mEq/L。镁为 0.9 mEq/L。最恰当的下一步是什么?
某练习动脉血气显示 pH 7.37,PaCO₂ 52 mmHg (6.9 kPa),HCO₃⁻ 29 mmol/L。原发性紊乱是呼吸性酸中毒。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⁻ 32 mmol/L。用预期 PaCO₂ = 0.7·HCO₃⁻ + 21 求预期PaCO₂。
在这条规则的 II 导联心电图上测量 QT 间期和 R–R 间期,然后用 Bazett 公式 QTc = QT/√RR(均以秒计)计算经心率校正的QTc。答案以秒表示,保留三位小数。
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。
一名护理助理汇报了四位患者的情况。哪项汇报需要护士首先关注?
A patient with a severe asthma attack had a PaCO₂ of 32 mmHg (4.3 kPa) on arrival. An hour later it is 46 mmHg (6.1 kPa), and the patient seems tired. What does this suggest?
答案: A · Theophylline toxicity
Theophylline has a narrow therapeutic window. Toxicity causes nausea, vomiting, tachycardia, arrhythmias, agitation and seizures. Levels are monitored, and many drugs and smoking status change its clearance. The nurse should hold the dose and report.
答案: A · 暂停给药并上报,因为可能发生中毒
常见规则是:如果心尖脉搏低于 60 次/分(或低于设定的参数),或出现恶心、呕吐、视觉障碍或新的心律失常等中毒表现,则暂停地高辛并通知开处方者。通常还需检查地高辛浓度、心电图、钾和肾功能。护士不得自行更改剂量。
答案: D · 安排紧急全血细胞计数,排查粒细胞缺乏症
硫脲类药物(卡比马唑、甲巯咪唑、丙硫氧嘧啶)可引起粒细胞缺乏症,这是一种罕见但危及生命的中性粒细胞下降。应教导患者立即报告咽痛、发热或口腔溃疡,并紧急检查血常规;如果中性粒细胞偏低则停药。
答案: C · Focal impaired awareness seizure
Focal impaired awareness seizures often come from the temporal lobe. They last about a minute or two, with automatisms such as lip smacking and fumbling, and are followed by confusion. Absence seizures are shorter and have no postictal phase.
答案: D · 癌细胞迅速分解引起的代谢急症
肿瘤细胞迅速死亡(通常在急性白血病或高级别淋巴瘤等快速生长的癌症开始治疗后)会释放钾、磷酸盐和核酸(转化为尿酸)。这可引起 AKI 和心律失常。
答案: A · Residual neuromuscular blockade
Remaining muscle relaxant causes weakness, poor head lift and shallow breathing in an awake patient. The nurse supports breathing, gives oxygen and calls the anaesthetist, who may give a reversal agent.
答案: A · Dull percussion and reduced breath sounds over the lung base
Fluid in the pleural space muffles breath sounds and makes percussion stony dull. A large effusion may push the trachea away from the affected side.
答案: B · To prevent accidental intravenous administration
Giving an oral or enteral medicine intravenously can be fatal. Enteral syringes with non-IV connectors, such as ENFit, make this wrong-route error much less likely.
答案: C · Referral for colonoscopy
A positive FIT means hidden blood in the stool, which may come from a polyp, cancer or other lesion, so a colonoscopy is needed to find the source. A positive screening test is never ignored, even without symptoms.核对依据: Fecal Occult Blood Test (FOBT) · MedlinePlus (NIH) (2024)
答案: A · 补镁;低镁使肾脏持续丢失钾
低镁使肾脏丢失钾,因此在补镁之前低钾血症无法纠正。两者在酒精使用障碍中都很常见。核对依据: Low blood potassium · MedlinePlus (NIH) (2025); Magnesium Blood Test · MedlinePlus (NIH) (2023)
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。
答案: PaCO₂ = 43.4 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: QTc = 0.371 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。
在通常上限之内(男性约 0.45 s,女性约 0.46 s)。(371 ms)
答案: 起搏心律,夺获失败
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。
夺获失败:起搏器发放了脉冲,但心脏没有反应。教科书把它视为需要紧急报告的情况,因为患者可能依赖起搏器。
答案: C · 一名腹部手术后一天的患者新出现烦躁不安,心率 124 次/分
手术后新出现的烦躁不安伴心率快可能意味着出血、脓毒症或缺氧。对这名 COPD 患者,SpO₂ 90% 是预期的,6 小时 300 mL(50 mL/h)是足够的尿量。
答案: A · Respiratory muscle fatigue with possible impending respiratory failure
Early in an asthma attack, fast breathing lowers the PaCO₂. A rising, “normal” value in a tiring patient means they can no longer move enough air, which is a warning sign of respiratory failure.
ExamProblems · examproblems.com/courses/medical-surgical-nursing