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 ECG change is classically linked with hyperkalaemia?
Two days after coronary artery bypass surgery, a patient feels palpitations. The pulse is irregularly irregular at 140/min and BP is 112/70 mmHg. Which rhythm is most likely?
Where is the zero point of an external ventricular drain usually levelled?
A drowsy patient's glucose meter shows "HI". What should the nurse do?
Which is a recognised cause of anaphylaxis during surgery?
A nurse teaches a patient with GORD. Which statement shows a need for further teaching?
低钠血症患者应特别监测:
The fluid in an underwater seal chest drain has stopped swinging with breathing. What could this mean?
In the third trimester of pregnancy, a woman's alkaline phosphatase (ALP) is about twice the usual adult range, and the other liver tests are normal. What is the best interpretation?
Two weeks after a sore throat, a child develops dark (cola-colored) urine, puffy eyes and high blood pressure. Urinalysis shows red cell casts and protein. Which condition is most likely?
练习数值:Na⁺ 152 mmol/L,葡萄糖 13.1 mmol/L,尿素 14.1 mmol/L。计算血清渗透压 Osm = 2·Na⁺ + 葡萄糖 + 尿素,取最接近的整数。
某练习血气显示代谢性碱中毒,HCO₃⁻ 34 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 Fridericia 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。
一位摸不到脉搏的患者,监护仪上显示这种有组织的心律(无脉性电活动)。成人复苏指南为它推荐哪种治疗?点击你的答案。
A nurse needs to give report on a patient to a colleague. Which information is the most important to include?
A patient admitted with a stroke this morning asks for a glass of water. What should the nurse do first?
答案: D · Tall, peaked T waves
Rising potassium causes tall, tented T waves, then a flattened P wave, a prolonged PR interval and a widening QRS that can progress to ventricular fibrillation or asystole. U waves suggest hypokalaemia; a sawtooth baseline is atrial flutter.
答案: D · Atrial fibrillation
New atrial fibrillation affects a large proportion of patients in the first days after cardiac surgery, often due to inflammation, electrolyte shifts and stress. Management includes a 12-lead ECG, checking potassium and magnesium, rate or rhythm control and considering anticoagulation.
答案: A · At the tragus of the ear
The EVD is levelled at the tragus, which approximates the foramen of Monro. If the head of the bed is changed, the drain must be re-levelled, because its height decides how much CSF drains.
答案: B · Treat it as very high, check ketones and escalate
"HI" means the glucose is above the meter's upper range. In a drowsy patient this may be DKA or HHS. A laboratory glucose, ketones, observations and urgent medical review are needed.
答案: A · Chlorhexidine skin preparation
Common causes of perioperative anaphylaxis include neuromuscular blockers, antibiotics, chlorhexidine and latex. Allergies are documented, and suspected reactions are investigated afterwards.
答案: A · "Peppermint tea after dinner will settle my reflux."
Peppermint can relax the lower oesophageal sphincter and may worsen reflux. Weight loss, stopping smoking and avoiding personal triggers are standard lifestyle measures.
答案: C · 意识混乱、头痛和癫痫发作
低钠使水进入脑细胞,导致恶心、头痛、意识混乱,严重时癫痫发作。必须缓慢纠正,以避免渗透性脱髓鞘。
答案: A · The tube may be kinked or blocked, or the lung may have fully re-expanded
Loss of swing can mean a kinked, clamped or blocked tube, or re-expansion of the lung. The nurse checks the tubing and the patient and reports the finding.
答案: A · A normal rise from placental ALP
The placenta produces ALP, so serum ALP normally rises in late pregnancy. With normal bilirubin, ALT and AST, this is expected. Symptoms such as severe itching or raised bile acids would need further review.核对依据: Alkaline Phosphatase · MedlinePlus (NIH) (2024)
答案: C · Post-streptococcal glomerulonephritis
Red cell casts show bleeding from the glomeruli, which is typical of glomerulonephritis. After a streptococcal infection, immune complexes inflame the glomeruli, causing hematuria, proteinuria, edema and hypertension. Cystitis and stones do not cause red cell casts.核对依据: Strep A Test · MedlinePlus (NIH) (2024)
答案: Osm = 331 mOsm/kg
衍生数值:计算所得的血清渗透压为 2·Na⁺ + 葡萄糖 + 尿素,各值均以 mmol/L 计(葡萄糖和 BUN 以 mg/dL 计时为 2·Na⁺ + 葡萄糖/18 + BUN/2.8);正常约为 275–295 mOsm/kg。P/F 比值是 PaO₂ 除以以小数表示的 FiO₂。海平面的肺泡氧分压为 PAO₂ = FiO₂·(760 − 47) − PaCO₂/0.8 mmHg,A–a 梯度为 PAO₂ − PaO₂。
答案: PaCO₂ = 44.8 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 = 0.438 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)。(438 ms)
答案: 心肺复苏(不可电击心律)
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: D · The patient’s current condition, recent changes and pending tasks
Effective handover covers the current status, changes, risks and outstanding tasks, often using a structure such as SBAR. Opinions and unrelated details distract from what matters.
答案: D · Check that a swallow screen has been done before giving anything by mouth
After a stroke, the patient stays NPO (nothing by mouth) until a swallow screen shows it is safe. Giving fluids first risks aspiration, even with a straw or thickener.
ExamProblems · examproblems.com/courses/medical-surgical-nursing