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。
Which emergency equipment should be kept at the bedside of a patient with a tracheostomy?
A patient with pneumonia has a heart rate of 118/min, BP 86/50 mmHg, RR 28/min and a high lactate. Sepsis is recognised. Which action should not be delayed?
一次癫痫发作已持续五分钟且仍在继续。通常的一线药物治疗是什么?
An 84-year-old man became more confused a week after starting oxybutynin. Infection has been ruled out. What should the nurse suspect?
Which early symptoms suggest local anaesthetic systemic toxicity?
A patient with a severe flare of ulcerative colitis develops abdominal distension, fever and tachycardia, and the stool frequency has dropped. What should the nurse suspect?
A patient on the ward has shingles with open blisters. Which people are most at risk from contact?
After a viral illness, a patient has sharp chest pain that is worse lying flat and eased by sitting forward. What is the most likely cause?
为什么肝衰竭患者即使没有服用华法林,INR 也可能升高?
为什么对肌肉量少的虚弱老年人,正常的肌酐可能具有误导性?
某练习血气显示 PaCO₂ 23 mmHg (3.1 kPa)。利用规则:在急性呼吸性碱中毒中,PaCO₂ 每比 40 低出 10 mmHg,HCO₃⁻ 下降 2 mmol/L,以HCO₃⁻ 24 mmol/L 为起点,求预期HCO₃⁻。
某练习血气显示代谢性酸中毒:pH 7.24,PaCO₂ 41 mmHg (5.5 kPa),HCO₃⁻ 17 mmol/L。把实测的PaCO₂与温特公式比较。点选你的解读。
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。
一位处于监护中的患者被发现无反应、呼吸不正常,且摸不到颈动脉搏动。监护仪显示这种有组织的心律。这种情况叫什么?点击你的答案。
Which patient is at the highest risk of falling?
A dehydrated child is to receive IV fluids with added potassium. Which finding should the nurse confirm first?
答案: B · Spare tubes (same size and one smaller), suction and oxygen
Bedside equipment usually includes spare tracheostomy tubes (same size and one size smaller), an obturator if used, suction with catheters, oxygen, a bag-valve-mask and tracheal dilators where policy requires. It is checked at every shift.
答案: C · Take blood cultures and give IV antibiotics within the first hour
In sepsis with shock, blood cultures, IV antibiotics within the first hour, IV fluids, lactate measurement, oxygen if hypoxic and urine output monitoring are started together. Cultures should not delay antibiotics. Persistent hypotension may need vasopressors in critical care.
答案: C · 苯二氮䓬类药物,如静脉劳拉西泮或颊黏膜咪达唑仑
持续五分钟或以上的发作(或反复发作且间歇期未恢复)按癫痫持续状态处理。首先给予苯二氮䓬类药物(有静脉通路时用静脉劳拉西泮;没有时用颊黏膜或鼻内咪达唑仑或直肠地西泮),发作持续时再用左乙拉西坦、苯妥英或丙戊酸等二线抗癫痫药。应检测血糖,仅在偏低时给予葡萄糖。
答案: C · Anticholinergic side effects of the drug
Anticholinergic drugs such as oxybutynin can cause confusion and worsen cognition in older people. The prescriber should review the medicine and the patient's overall anticholinergic burden.
答案: B · Tingling around the mouth, a metallic taste and tinnitus
High blood levels of local anaesthetic first cause CNS symptoms such as perioral tingling, metallic taste, tinnitus, light-headedness and confusion, then seizures and arrhythmias. The injection is stopped and help is called at once.
答案: C · Toxic megacolon
Toxic megacolon is dilatation of the inflamed colon with systemic toxicity and a high risk of perforation. Antimotility drugs and opioids are avoided, an abdominal X-ray is done and the surgical team is involved.
答案: D · Pregnant women and immunocompromised people who have not had chickenpox
Someone who has never had chickenpox can catch chickenpox from contact with shingles blisters. Non-immune pregnant and immunocompromised people are at particular risk, so lesions are covered and precautions followed.
答案: D · Pericarditis
Pericarditis typically causes sharp, positional chest pain relieved by sitting forward, sometimes with a pericardial rub. Viral infection is a common cause.
答案: A · 肝脏合成大多数凝血因子,因此合成减少
肝脏合成大多数凝血因子,包括依赖维生素 K 的因子。在严重肝病中,它们的合成减少,因此 INR 升高。INR 升高是反映肝衰竭严重程度的指标之一。核对依据: Prothrombin Time Test and INR (PT/INR) · MedlinePlus (NIH) (2024)
答案: B · 肌肉少则产生的肌酐少,掩盖了肾功能的下降
肌酐由肌肉产生。肌肉很少的人产生的肌酐很少,因此即使肾功能下降,数值也可能看起来正常。基于肌酐的 eGFR 同样可能高估肾功能,因此在给予经肾脏清除的药物确定剂量时,可采用实测肌酐清除率或基于胱抑素 C 的估算值。核对依据: Creatinine blood test · MedlinePlus (NIH) (2025)
答案: HCO₃⁻ = 20.6 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: 合并呼吸性酸中毒
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: QTc = 0.404 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)。(404 ms)
答案: 无脉性电活动(PEA)
无脉性电活动(PEA):PEA 无法从心电图条带上看出。监护仪显示有组织的电活动(VF、VT 或心搏停止以外的心律),但患者摸不到脉搏,因此要通过检查患者来识别。在成人复苏指南中,PEA 和心搏停止是不可电击的心脏骤停心律:进行高质量心肺复苏,尽快使用肾上腺素,并寻找可逆原因(5H 和 5T,如低血容量、缺氧、张力性气胸和心脏压塞)。VF 和无脉性 VT 是可电击心律。
PEA 在床旁识别,绝不能仅凭心电图条带。这是考试练习,不是临床指南。
答案: C · An 84-year-old taking a diuretic who has fallen before and gets up at night
A previous fall is one of the strongest risk factors. Older age, diuretics and getting up at night to urinate add further risk, so this patient needs fall precautions.
答案: D · That the child is passing urine
Potassium is not added to IV fluids until the child is passing urine, because poor kidney function can let potassium build up to dangerous levels.
ExamProblems · examproblems.com/courses/medical-surgical-nursing