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。
哪种药物类别组合可提高射血分数降低的心力衰竭患者的生存率?
A patient with severe aortic stenosis is prescribed glyceryl trinitrate (nitroglycerin) for chest pain. Why should the nurse use particular caution?
A patient has taken metformin for many years and now has tingling feet and a low haemoglobin. Which blood test is most relevant?
During haemodialysis, a patient suddenly becomes breathless with chest pain, and air is seen in the line. What should the nurse do first?
During the first infusion of a monoclonal antibody such as rituximab, which problem is most important to watch for?
During a nasogastric feed, a patient starts coughing and SpO₂ falls from 96% to 89%. What should the nurse do first?
Why is it important to prevent hypothermia during and after surgery?
一名急性消化道出血患者心率 120 次/分,血压 90/60 mmHg。呼救后,护理的首要任务是什么?
A patient had a right mastectomy with removal of axillary lymph nodes. Where is the best place to draw blood?
A patient with severe sepsis is oozing blood from IV sites. Platelets 40 × 10³/µL, fibrinogen low, D-dimer very high, PT and aPTT both prolonged. Which condition fits best?
某练习血气显示代谢性酸中毒,HCO₃⁻ 6 mmol/L。用温特公式求预期PaCO₂(范围的中心),单位 mmHg。
某练习血气显示代谢性碱中毒,HCO₃⁻ 30 mmol/L。用预期 PaCO₂ = 0.7·HCO₃⁻ + 21 求预期PaCO₂。
这条 II 导联心电图条带显示窦性心律伴一次停顿。测量 停顿,即跨越停顿的 R–R 间期,单位为秒。
识别这条 II 导联心电图上的节律。点击你的答案。
A nurse sees a nursing assistant leave a confused patient’s bed in the highest position after care. What should the nurse do?
Several patients on a unit develop diarrhea within two days. What should the nurse do first?
答案: A · ACE 抑制剂或 ARNI、β 受体阻滞剂、MRA 和 SGLT2 抑制剂
现行指南推荐 HFrEF 使用四类可改变疾病进程的药物:ACE 抑制剂、ARB 或 ARNI(沙库巴曲/缬沙坦);有循证依据的 β 受体阻滞剂;MRA(螺内酯或依普利酮);以及 SGLT2 抑制剂。袢利尿剂和地高辛改善症状,但不改善生存率。NSAID 会使心力衰竭恶化。
答案: A · Vasodilators can cause a severe fall in BP with a fixed outflow obstruction
In severe aortic stenosis, cardiac output is fixed by the narrow valve. Vasodilators lower preload and afterload, and the heart cannot compensate, so the blood pressure can fall sharply and cause syncope. They are used with care and close monitoring.
答案: B · Vitamin B12 level
Long-term metformin can lower vitamin B12 absorption, causing anaemia and neuropathy that may be mistaken for diabetic neuropathy. B12 levels are checked, especially when symptoms appear.
答案: C · Clamp the lines and lay the patient left side down, head low
In suspected air embolism, the blood lines are clamped at once, the pump stopped, and the patient positioned on the left side with the head down to trap air in the right atrium. Oxygen is given and emergency help called.
答案: A · An infusion reaction, such as fever, rigors or breathlessness
Infusion-related reactions are most common with the first dose. Premedication, a slow starting rate, close monitoring and readiness to stop the infusion and treat anaphylaxis are standard.
答案: B · Stop the feed and assess the airway and breathing
Coughing and desaturation suggest aspiration or a displaced tube. The feed is stopped, the patient is sat up, oxygen is given as needed, and medical review and checking of tube position follow.
答案: A · It increases the risk of wound infection, bleeding and cardiac complications
Inadvertent perioperative hypothermia impairs clotting and immune function and increases cardiac events and wound infection. Patients are warmed actively and their temperature monitored.
答案: B · 建立大口径静脉通路,准备补液或输血
心动过速和低血压提示大量失血。首先进行 ABCDE 评估、建立粗口径静脉通路、抽血(包括交叉配血)并进行复苏,随后行内镜检查。
答案: D · The left arm
After axillary node removal, venipuncture and blood pressure readings are usually avoided on that side to reduce the risk of lymphedema and infection. The opposite arm is used whenever possible, according to policy.
答案: D · Disseminated intravascular coagulation (DIC)
In DIC, widespread clotting consumes platelets and clotting factors, so PT and aPTT are prolonged and fibrinogen falls, while clot breakdown raises the D-dimer. ITP lowers platelets only, and hemophilia A prolongs only the aPTT.核对依据: Fibrinogen blood test · MedlinePlus (NIH) (2025); Prothrombin time (PT) · MedlinePlus (NIH) (2025); D-Dimer Test · MedlinePlus (NIH) (2024)
答案: PaCO₂ = 17 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。
答案: PaCO₂ = 42 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: 停顿 = 1.96 s
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)。
停顿中没有出现 P 波,且停顿不是 P–P 周期的整数倍:窦性停搏。恰好两个或三个周期的停顿则提示窦房传导阻滞。
答案: 心脏停搏
室性节律:室性心动过速是连续三个或以上宽大(0.12 s 或以上)的波群,频率超过 100 次/分,通常为 150–250 次/分,节律规则,没有相关的 P 波。心室颤动是紊乱、不规则的波形,无法辨认 P 波、QRS 波群或 T 波,也没有可计数的频率。心脏停搏是几乎平直的线,没有心室活动;平直线一定要通过检查患者、导联和增益并换一个导联来确认。在复苏指南中,室颤和无脉性室速是可电击心律,心脏停搏则不是。
平直线必须核实:查看患者、导联和增益,并换看第二个导联,因为电极脱落或细颤型室颤都可能看起来像心脏停搏。
答案: C · Lower the bed now and remind the assistant why it matters
A high bed increases the risk of a serious fall, so the nurse corrects it at once and gives brief, clear feedback. Leaving it or delaying feedback leaves the patient at risk.
答案: D · Place affected patients on contact precautions and inform infection control
A cluster of diarrhea may be an outbreak, for example of C. difficile or norovirus. Contact precautions and early notification of infection control limit spread.
ExamProblems · examproblems.com/courses/medical-surgical-nursing