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。
Why are patients with mitral stenosis at high risk of atrial fibrillation?
A 28-year-old woman taking the combined pill comes in breathless and anxious. RR is 30/min, heart rate 118/min and SpO₂ 90% on air. A colleague says it is a panic attack. What should the nurse conclude?
How does bladder training help urge incontinence?
A patient with Addison's disease has been vomiting for a day. They are confused, with BP 78/40 mmHg, sodium 126 mmol/L and potassium 6.0 mmol/L. What is the priority?
Why is the "whoosh" test no longer used to check nasogastric tube position?
A patient taking IV antibiotics has three unexplained loose stools in 24 hours. What should the nurse do first?
A patient without diabetes is started on high-dose prednisolone. Why might capillary blood glucose be monitored?
A day after surgery, a patient's haemoglobin has fallen from 125 g/L to 85 g/L (12.5 to 8.5 g/dL) and their heart rate has risen to 118/min. What is the priority?
对于出现意识模糊和扑翼样震颤的严重肝病患者,哪项实验室数值最能反映原因?
After lying on the floor for many hours, a patient has a CK of 40,000 U/L, a potassium of 6.1 mEq/L and dark urine. Which prescribed treatment is the priority?
某练习动脉血气显示 pH 7.29,PaCO₂ 52 mmHg (6.9 kPa),HCO₃⁻ 24 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 pH 7.33,PaCO₂ 33 mmHg (4.4 kPa),HCO₃⁻ 17 mmol/L,Na⁺ 133,Cl⁻ 101 mmol/L。利用阴离子间隙和 Δ 比值,点选最合适的解读。
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 nasogastric tube has just been placed for feeding. What must happen before the first feed is given?
A patient opens their eyes only to pain, uses inappropriate words and withdraws from pain. What is the Glasgow Coma Scale score?
答案: B · The left atrium enlarges as it pushes blood through the narrow valve
A narrowed mitral valve raises pressure in the left atrium, which dilates. A stretched atrium is prone to atrial fibrillation, and blood stasis there carries a high risk of clots and stroke. Anticoagulation is therefore essential in mitral stenosis with AF.
答案: B · Low oxygen saturation is not explained by anxiety; PE must be excluded
Panic-related hyperventilation causes respiratory alkalosis but normal oxygen saturation. Hypoxaemia with tachycardia in a woman taking oestrogen suggests PE. She needs oxygen, urgent medical assessment and investigation. Paper-bag rebreathing is unsafe and can worsen hypoxaemia.
答案: D · The time between voids is slowly increased
In bladder training, the patient follows a schedule and gradually lengthens the time between voids while using urge-suppression techniques. Over weeks, bladder capacity and control improve. Very low fluid intake makes urine concentrated and irritating.
答案: A · IV hydrocortisone straight away, plus IV fluids
An adrenal crisis is life-threatening. IV or IM hydrocortisone is given immediately, without waiting for tests, together with IV saline and checks of glucose and electrolytes. Vomiting prevents tablets from being absorbed.
答案: D · Air can be heard even when the tube is in the lung
Auscultation of injected air cannot distinguish the stomach from the lungs or oesophagus, and misplaced tubes have caused deaths. pH testing of aspirate or X-ray is used instead.
答案: D · Isolate the patient and send a stool sample for testing
Unexplained diarrhoea in a patient on antibiotics should be treated as possible C. difficile. The patient is isolated promptly, a stool sample is sent and the antibiotics are reviewed with the medical team.
答案: A · Steroids can raise the blood glucose
Glucocorticoids increase glucose production and insulin resistance, causing steroid-induced hyperglycaemia. Glucose monitoring identifies patients who need treatment.
答案: D · Escalate urgently, as the patient may be bleeding
A large fall in haemoglobin with tachycardia suggests ongoing blood loss. The nurse assesses the patient with ABCDE, checks wounds and drains and escalates for urgent review.
答案: B · 血清氨升高
衰竭的肝脏无法将氨转化为尿素,因此氨蓄积,导致肝性脑病。乳果糖常用于减少肠道对氨的吸收。核对依据: Ammonia Levels · MedlinePlus (NIH) (2026); Loss of brain function - liver disease · MedlinePlus (NIH) (2025)
答案: B · Large-volume IV fluids with cardiac monitoring
Rhabdomyolysis releases myoglobin, which can cause acute kidney injury, and potassium, which can cause arrhythmias. Early aggressive IV fluids, a target urine output and cardiac monitoring are priorities. NSAIDs and potassium would worsen kidney injury and hyperkalemia.核对依据: Rhabdomyolysis · MedlinePlus (NIH) (2025)
答案: 未代偿
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: 合并正常间隙酸中毒
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: 心房颤动
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: 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: B · Placement is confirmed by an approved method
A newly placed feeding tube can enter the airway without obvious symptoms, so placement is confirmed before anything is given. Methods differ: US practice usually requires an X-ray for a new feeding tube, while UK guidance uses aspirate pH testing (5.5 or below) first, with X-ray if that fails. Air “whoosh” tests and waiting for coughing are not reliable.
答案: D · 9
Eyes open to pain scores 2, inappropriate words score 3 and withdrawal from pain scores 4, giving 9. A score of 8 or less often means the patient cannot protect their airway.
ExamProblems · examproblems.com/courses/medical-surgical-nursing