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。
During airway suctioning, when should suction be applied?
A patient with pneumonia has a temperature of 39 °C, pain and a sinus tachycardia of 122/min. BP is normal. What is the best way to manage the heart rate?
A patient has just started haemodialysis. What usually happens to their protein needs?
A patient with CKD has a potassium of 6.5 mmol/L. Which medicine combination is the most likely contributor?
In the UK National Early Warning Score (NEWS2), what does an aggregate score of 5 or more usually trigger?
A patient with recurrent diverticulitis reports passing air and faecal matter in the urine. What is the most likely cause?
What should a patient be told before using sublingual glyceryl trinitrate (GTN, nitroglycerin) spray for angina?
A patient with several days of vomiting and diarrhoea has low blood pressure, low urine output and a rising creatinine. Which description fits best?
A patient with a low clinical probability of deep vein thrombosis has a normal (negative) D-dimer. What is the best interpretation?
A patient has fever, confusion, a platelet count of 15 × 10³/µL, anemia with fragmented red cells (schistocytes) and a raised creatinine. Clotting times are normal. Which condition should be suspected?
某练习动脉血气显示 pH 7.64,PaCO₂ 23 mmHg (3.1 kPa),HCO₃⁻ 24 mmol/L。原发性紊乱是呼吸性碱中毒。代偿到什么程度?点选你的答案。
在海平面,某练习血气取自吸入 21% 氧气时,显示 PaO₂ 83 mmHg (11.1 kPa),PaCO₂ 34 mmHg (4.5 kPa)。用 PAO₂ = FiO₂·(760 − 47) − PaCO₂/0.8 求A–a 梯度。
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。
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 nurse teaches a patient to use an incentive spirometer. Which statement shows a need for further teaching?
一名患肺炎的老年患者新出现意识模糊。首先采取哪项行动?
答案: A · Only while withdrawing the catheter
The catheter is inserted without suction and suction is applied as it is withdrawn, with each pass kept short. This limits mucosal trauma and hypoxaemia. The patient is monitored for desaturation and bradycardia.
答案: A · Treat the fever, pain and possible dehydration, then reassess
Sinus tachycardia is usually a physiological response to fever, pain, hypovolaemia, anxiety, hypoxia or sepsis. Treating the cause (antipyretics, analgesia, fluids, oxygen if needed) is appropriate, while watching for sepsis. Rate-slowing drugs can be harmful by masking compensation.
答案: B · They increase, because dialysis removes amino acids
Before dialysis, a moderate protein intake may be advised. Dialysis removes amino acids and protein, so needs rise, and malnutrition is a common risk. A renal dietitian sets individual targets.
答案: A · Ramipril, spironolactone and trimethoprim
ACE inhibitors and spironolactone reduce aldosterone effect, and trimethoprim blocks potassium secretion in the distal tubule. Together, in CKD, they can cause dangerous hyperkalaemia. Loop diuretics, salbutamol and insulin lower potassium.
答案: C · An urgent review by a clinician skilled in acute illness
NEWS2 scores respiratory rate, SpO₂, oxygen use, BP, pulse, consciousness or new confusion, and temperature. A score of 5–6 needs an urgent response, and 7 or more an emergency response.
答案: B · A fistula between the colon and the bladder
Pneumaturia and faecaluria suggest a colovesical fistula, a recognised complication of diverticulitis (and Crohn's disease or cancer). Recurrent urinary infections are common, and surgery is usually needed.
答案: D · Sit down before using it, as it can cause dizziness and low blood pressure
GTN causes vasodilation, which can lead to headache, flushing, dizziness and hypotension. Patients should sit, and seek emergency help if the pain does not settle after the advised doses.
答案: D · Pre-renal acute kidney injury from poor perfusion, treated by restoring fluid volume
Fluid loss reduces kidney perfusion, causing pre-renal AKI. Prompt fluid replacement can restore function before the kidney tissue itself is damaged.
答案: B · A DVT is unlikely and can usually be ruled out
D-dimer is very sensitive, so a negative result in a patient with low clinical probability makes DVT or PE unlikely. A positive result is not specific, because surgery, infection, pregnancy and cancer also raise D-dimer; imaging is then needed.核对依据: D-Dimer Test · MedlinePlus (NIH) (2024)
答案: A · Thrombotic thrombocytopenic purpura (TTP)
TTP causes small clots that consume platelets, break red cells (microangiopathic hemolysis) and damage the brain and kidneys, while clotting times usually stay normal. It is an emergency treated with plasma exchange; platelet transfusion is generally avoided.核对依据: Thrombotic thrombocytopenic purpura · 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: A–a 梯度 = 24.23 mmHg
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: QTc = 0.39 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)。(390 ms)
答案: 二度 I 型房室传导阻滞(文氏现象)
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。
答案: A · “I will blow into it as hard and fast as I can.”
An incentive spirometer is used by breathing in slowly and deeply, then holding the breath briefly. Blowing into it does not expand the lungs.
答案: A · 检查血氧饱和度和其他生命体征
新出现的意识模糊可能由缺氧、脓毒症或低血糖引起。首先评估氧合和生命体征。约束和镇静药处理的是行为而不是病因,并可能使谵妄恶化。
ExamProblems · examproblems.com/courses/medical-surgical-nursing