A 47-year-old man comes to the physician because of a 7-week history of cough, shortness of breath, and daily copious sputum production. He has had frequent respiratory tract infections over the past several years. Current medications include dextromethorphan and guaifenesin as needed. He does not smoke cigarettes. His temperature is 37.1°C (98.8°F), pulse is 88/min, respirations are 21/min, and blood pressure is 133/84 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 95%. Diffuse crackles and wheezing are heard on auscultation over bilateral lung fields. A CT scan of the chest is shown. The patient is at greatest risk for which of the following complications?

Infection with Rhizopus species

Neoplastic growth of pleural cells

A 68-year-old man presents with shortness of breath, particularly when walking up stairs and when lying down to go to sleep at night. He also complains of a chronic cough and states that he now uses 2 extra pillows at night. The patient has a history of type 2 diabetes that is well-managed with metformin. He also takes Prozac for a long-standing history of depression. The patient has a 60-pack-year smoking history. He also has a history significant for alcohol abuse, but he quit cold turkey 15 years ago when his brother was killed in a drunk driving accident. Both he and his brother were adopted, and he does not know other members of his biological family. Despite repeated efforts of patient counseling, the patient is not interested in quitting smoking. The physical exam is significant for an obese male using accessory muscles of respiration. The vital signs include: temperature 36.8°C (98.2°F), heart rate 95/min, respiratory rate 16/min, and blood pressure 130/85 mm Hg. The oxygen saturation is 90% on room air. Additional physical exam findings include cyanotic lips, peripheral edema, hepatomegaly, and ascites. The cardiovascular exam is significant for an S3 heart sound and elevated JVP. The pulmonary exam is significant for expiratory wheezing, diffuse rhonchi, and hyperresonance on percussion. The laboratory test results are as follows: BUN 15 mg/dL pCO2 60 mm Hg Bicarbonate (HCO3) 32 mmol/L Creatinine 0.8 mg/dL Glucose 95 mg/dL Serum chloride 103 mmol/L Serum potassium 3.9 mEq/L Serum sodium 140 mEq/L Total calcium 2.3 mmol/L Hemoglobin 26 g/dL Bilirubin total 0.9 mg/dL Bilirubin indirect 0.4 mg/dL Iron 100 Ferritin 70 TIBC 300 The posterior-anterior chest X-ray is shown in the image. Which of the following interventions is indicated for decreasing the mortality of this patient?

Both smoking cessation and oxygen administration

A 35-year-old male presents to the emergency room with difficulty breathing. He is accompanied by his wife who reports that they were eating peanuts while lying in bed on their backs when he suddenly started coughing profusely. He has a significant cough and has some trouble breathing. His past medical history is notable for obesity, obstructive sleep apnea, seasonal allergies, and alcohol abuse. He uses a continuous positive airway pressure machine nightly. His medications include cetirizine and fish oil. He has a 10 pack-year smoking history. His temperature is 98.6°F (37°C), blood pressure is 125/30 mmHg, pulse is 110/min, and respirations are 23/min. Which of the following lung segments is most likely affected in this patient?

Superior segment of right inferior lobe

Posterior segment of right superior lobe

Inferior segment of right inferior lobe

Anterior segment of right superior lobe

Inferior segment of left inferior lobe

A 63-year-old man presents to the clinic complaining of burning bilateral leg pain which has been increasing gradually over the past several months. It worsens when he walks but improves with rest. His past medical and surgical history are significant for hypertension, hyperlipidemia, diabetes, and a 40-pack-year smoking history. His temperature is 99.0°F (37.2°C), blood pressure is 167/108 mm Hg, pulse is 88/min, respirations are 13/min, and oxygen saturation is 95% on room air. Physical exam of the lower extremities reveals palpable but weak posterior tibial and dorsalis pedis pulses bilaterally. Which of the following is the best initial treatment for this patient's symptoms?

Balloon angioplasty with stenting

Pulmonary risk evaluation for USMLE Step 1: High-Yield Surgery Lessons

Risk Factors - The Usual Suspects

Key predictors for postoperative pulmonary complications (PPCs) divide into patient-specific and procedure-specific categories.

Patient-Related Factors	Procedure-Related Factors
* Age >60 years	* Surgical Site (greatest risk)
* COPD / Asthma	- Aortic > Thoracic > Abdominal
* Active Smoking (w/in 2 mo)	* Anesthesia > 3 hours
* Obstructive Sleep Apnea (OSA)	* General Anesthesia
* Congestive Heart Failure (CHF)	* Emergency Surgery
* Functional Dependence	* NG tube placement
* Serum Albumin <3.5 g/dL
* BUN >21 mg/dL

⭐ The single most important predictor of postoperative pulmonary risk is the surgical site. Aortic and thoracic surgeries carry the highest risk.

Clinical & PFT Assessment - Sizing Up the Lungs

Clinical Predictors:
- Functional capacity: Inability to climb 2 flights of stairs (< 4 METs) is a key risk marker.
- Smoking: Advise cessation >8 weeks pre-op.
- Symptoms: Chronic cough, dyspnea, or wheezing.
- Comorbidities: COPD, asthma, obesity (BMI >30), obstructive sleep apnea (OSA).
Pulmonary Function Tests (PFTs):
- Not routine. Indicated for patients undergoing lung resection or with unexplained dyspnea.
- High-risk markers for non-resection surgery:
  - FEV₁ < 1.5 L
  - PaCO₂ > 45 mmHg on baseline ABG.

⭐ For lung resection, the predicted postoperative FEV₁ (ppoFEV₁) is the most critical value. A ppoFEV₁ < 40% of predicted signals very high risk.

METs equivalents for common activities

Risk Reduction Strategies - Pre-Op Power-Ups

Smoking Cessation:
- The single most important intervention.
- Advise cessation at least 4-8 weeks pre-op to significantly ↓ risk of post-op complications.
- Nicotine replacement therapy can aid success.
Optimize Underlying Lung Disease:
- Asthma: Ensure symptoms are well-controlled. Consider a pre-op "tune-up" with inhaled corticosteroids or a short course of oral steroids if recently unstable. Administer pre-op SABA.
- COPD: Optimize with bronchodilators (e.g., tiotropium, albuterol). Treat exacerbations with systemic steroids and/or antibiotics.
Lung Expansion & Secretion Clearance:
- Pre-operative patient education is key for post-op compliance.
- Techniques: Incentive Spirometry (IS), deep breathing exercises, directed coughing.
- Consider pre-op Inspiratory Muscle Training (IMT) for high-risk patients.
Infection Control:
- Treat any existing bronchitis or pneumonia with appropriate antibiotics before elective surgery.

⭐ Any period of smoking cessation is beneficial, but stopping <2 weeks before surgery may paradoxically increase postoperative pulmonary complications due to transiently increased sputum production. The ideal window is >4 weeks.

Patient using incentive spirometer with diagram

Surgical site is the most important predictor of postoperative pulmonary complications (PPCs).

Major risk factors include COPD, smoking, obstructive sleep apnea (OSA), age >60, and ASA class >II.

Advise smoking cessation at least 4 weeks pre-operatively to reduce risk.

Routine PFTs are not recommended; consider for unexplained dyspnea or planned lung resection.

Atelectasis is the most common PPC, usually developing within 48 hours post-op.

Prevention involves pre-op optimization and post-op lung expansion maneuvers like incentive spirometry.

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