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 do clopidogrel and ticagrelor work?
A patient with stable severe COPD has a blood gas showing pH 7.37, a raised PaCO₂ and a raised bicarbonate. How should this be interpreted?
为什么在 DKA 静脉输注胰岛素时必须密切监测钾?
A patient has frothy urine and marked leg swelling. Serum albumin is 18 g/L (1.8 g/dL), and BP is normal. The urine shows heavy protein but little blood. What is most likely?
What is TENS?
Using the adult rule of nines, what is the total burn area of the whole right arm plus the whole front of the trunk (both with partial-thickness burns)?
A patient is receiving enteral feeding through a nasogastric tube. How should they be positioned during feeding?
A patient has a painful, punched-out ulcer on the toes, with a cold, pale foot and weak foot pulses. Which type of ulcer is most likely?
一名室性心律失常患者的监护仪上显示扭转样图形(尖端扭转型室速)。常静脉给予哪种电解质作为治疗?
Which cerebrospinal fluid (CSF) pattern most strongly suggests bacterial meningitis?
某练习血气显示 PaCO₂ 63 mmHg (8.4 kPa)。利用规则:在急性呼吸性酸中毒中,PaCO₂ 每比 40 高出 10 mmHg,HCO₃⁻ 升高 1 mmol/L,以HCO₃⁻ 24 mmol/L 为起点,求预期HCO₃⁻。
某练习血气显示呼吸性酸中毒:pH 7.32,PaCO₂ 70 mmHg (9.3 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。
这条 II 导联心电图显示房室传导阻滞,所以心房和心室以不同的频率搏动。测量 P–P 间期,求出心房率(单位:次/分,1500 法,取整数)。
A patient has a reddened area on the sacrum that does not blanch when pressed. What is the priority action?
During surgery under general anesthesia, a patient develops rising end-tidal carbon dioxide, muscle rigidity and a rapidly increasing temperature. Which drug should the nurse anticipate?
答案: B · They block the platelet ADP (P2Y12) receptor
Clopidogrel, prasugrel and ticagrelor block the P2Y12 ADP receptor on platelets, reducing aggregation. With aspirin, they form dual antiplatelet therapy after acute coronary syndromes and stents. Warfarin inhibits vitamin K-dependent factors; dabigatran inhibits thrombin.
答案: C · Chronic respiratory acidosis with metabolic compensation
In chronic CO₂ retention, the kidneys retain bicarbonate over days, bringing the pH back towards normal. A normal pH with high PaCO₂ and high bicarbonate is compensated chronic respiratory acidosis. These patients usually have target saturations of 88–92%.
答案: A · 胰岛素使钾进入细胞,因此血钾可能迅速下降
DKA 患者全身钾严重缺乏,即使最初血清钾正常或偏高。胰岛素使钾转移到细胞内,可引起危险的低钾血症。应经常检测钾,并按医嘱加入液体;如果钾很低,可能要推迟胰岛素,直到开始补钾。
答案: D · Nephrotic syndrome
Heavy proteinuria, very low albumin and oedema point to nephrotic syndrome. Nephritic syndrome is mainly haematuria with hypertension and reduced urine output. The cause is investigated, often with a biopsy.
答案: D · A device that sends mild electrical pulses through skin pads
TENS is thought to reduce pain partly through the gate-control mechanism. It is non-invasive and patient-controlled, but is avoided over certain areas and with some implanted devices.
答案: D · 27%
The whole arm is 9% and the front of the trunk 18%, giving 27% total body surface area. Superficial (redness only) areas would not be counted.
答案: A · With the head of the bed raised to at least 30 degrees
Keeping the head raised to at least 30–45° during feeding and for a period afterwards lowers the risk of aspiration pneumonia.
答案: C · An arterial ulcer
Arterial ulcers are usually on the feet or toes, painful and punched-out, with signs of poor perfusion. Venous ulcers are usually around the ankle, shallow and associated with swelling and skin staining.
答案: D · 硫酸镁
静脉硫酸镁是尖端扭转型室速的标准药物治疗,即使血清镁正常也应使用。低镁和低钾都会延长 QT 间期并增加风险。
答案: B · Cloudy fluid, low glucose, high protein, many neutrophils
Bacterial meningitis typically gives cloudy CSF with many neutrophils, high protein and low glucose, because bacteria and white cells use glucose. Viral meningitis usually shows lymphocytes with a normal glucose; option C is normal CSF.核对依据: CSF glucose test · MedlinePlus (NIH) (2025); CSF cell count · MedlinePlus (NIH) (2025); CSF total protein · MedlinePlus (NIH) (2025)
答案: HCO₃⁻ = 26.3 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。
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: 室性二联律
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。
答案: 心房率 = 83 bpm
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。
2:1 房室传导阻滞:每隔一个 P 波不下传,所以心房率是心室率的两倍。
答案: D · Relieve pressure on the area by changing position regularly
Non-blanching redness is a stage 1 pressure injury. Relieving pressure through repositioning and support surfaces is the priority; massage can damage tissue further.
答案: A · Dantrolene
Malignant hyperthermia is a reaction to some anesthetic agents that causes hypermetabolism. The triggering drug is stopped and dantrolene is given, with active cooling and support.
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