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。
一名近期卒中且吞咽困难的患者出现发热和右下肺湿啰音。最可能的原因是什么?
An older patient's varicose vein bursts at the ankle and bleeds heavily. What is the most effective first aid?
A patient with CKD is booked for a CT scan with iodinated contrast. Which measure helps protect the kidneys?
Why might a frail 88-year-old with type 2 diabetes have a less strict HbA1c target?
Why do patients usually have a dental review before radiotherapy to the head and neck?
Which preoperative blood result should the nurse report to the team before elective surgery?
A patient without diabetes is started on high-dose prednisolone. Why might capillary blood glucose be monitored?
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 is scheduled for a liver biopsy. Which laboratory results should the nurse check before the procedure?
Ten minutes into a red cell transfusion, a patient develops fever, chills, low back pain and dark urine. After stopping the transfusion, what should the nurse do next?
某练习动脉血气显示 pH 7.38,PaCO₂ 26 mmHg (3.5 kPa),HCO₃⁻ 15 mmol/L。原发性紊乱是代谢性酸中毒。代偿到什么程度?点选你的答案。
练习数值:Na⁺ 138,Cl⁻ 106,HCO₃⁻ 11 mmol/L。使用 AG = Na⁺ − (Cl⁻ + HCO₃⁻) 计算 Δ 比值 (AG − 12)/(24 − HCO₃⁻)。保留两位小数。
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。
这条 II 导联心电图显示房室传导阻滞,心室节律不规则。使用 6 秒法求出心室率(单位:次/分)。
During an IV vancomycin infusion, a patient develops flushing and itching of the face and neck. What should the nurse do first?
四名患者同时到达急诊科。应先看谁?
答案: B · 吸入性肺炎
卒中后的吞咽困难增加了误吸的风险。误吸物常进入右下叶,因为右主支气管更宽、更垂直。吞咽筛查、直立体位和口腔护理可降低风险。
答案: C · Lie the patient down, raise the leg and press firmly on the site
Bleeding from a varicose vein can be dramatic. Lying the patient flat and raising the leg above heart level lowers venous pressure, and firm direct pressure stops most bleeds. Medical review is needed afterwards, as it can recur.
答案: A · Good hydration around the scan, often with IV fluids
Iodinated contrast can contribute to AKI in at-risk patients. Good hydration, using the lowest dose needed, avoiding nephrotoxic drugs and checking kidney function afterwards help reduce the risk.
答案: C · To reduce the risk of hypos, falls and confusion
In frail older adults, tight control brings little long-term benefit and a high risk of hypoglycaemia, which can cause falls, fractures and confusion. Targets are individualised to balance safety and quality of life.
答案: C · It causes dry mouth and raises the risk of decay and jaw damage
Head and neck radiotherapy damages salivary glands, causing xerostomia and dental decay, and can cause osteoradionecrosis of the jaw after extractions. Dental treatment is done first, with careful oral hygiene and fluoride.
答案: D · Potassium 2.9 mmol/L
Normal potassium is about 3.5–5.0 mmol/L. Hypokalaemia increases the risk of arrhythmias during anaesthesia and needs correction before elective surgery. The other results are within normal ranges.
答案: B · 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: C · 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: C · Platelet count and PT/INR
Liver biopsy carries a risk of bleeding, and liver disease often lowers platelets and clotting factors. Platelets and PT/INR are checked beforehand, and abnormal results are reported so they can be corrected or the procedure postponed.核对依据: Liver biopsy · MedlinePlus (NIH) (2025)
答案: C · Keep the IV open with normal saline using new tubing and call the provider
These signs suggest an acute hemolytic reaction. The transfusion is stopped, the line is kept open with normal saline through new tubing, the provider and blood bank are informed, and the bag, tubing and blood and urine samples are sent for testing as per policy.核对依据: Hemolytic transfusion reaction · MedlinePlus (NIH) (2025)
答案: 完全代偿
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。
临床上还应检查预期代偿:按温特公式,预期 PaCO₂ 为 28.5–32.5 mmHg,所以实测 26 mmHg 提示合并呼吸性碱中毒(混合性紊乱)。上面的答案是按 ROME 法的考试分类。
答案: Δ 比值 = 0.6923
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。
低于 1:合并正常阴离子间隙酸中毒。
答案: QTc = 0.379 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)。(379 ms)
答案: 心室率 = 50 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。
二度 II 型:每 3 个 QRS 波群对应 4 个 P 波,PR 恒定。
答案: B · Stop or slow the infusion and inform the provider
Flushing of the upper body during vancomycin is usually an infusion reaction related to the rate. The nurse stops or slows the infusion, assesses for anaphylaxis and informs the provider.
答案: C · 一名 2 岁的儿童,流口水,身体前倾,有喘鸣
流口水、前倾(三脚架)姿势和喘鸣提示严重的上气道梗阻,如会厌炎,可能迅速变成完全梗阻。应让孩子保持平静,在气道专家到场之前不要检查咽喉。
ExamProblems · examproblems.com/courses/medical-surgical-nursing