Respiratory III — Lung Cancer, PE, COPD & Asthma

0 · How to Use This Framework 🧭

This is not a list of diseases to memorize. It is one thinking process you run on every respiratory disorder. Learn the six questions and you can reason through a disease you have never seen.

Sort every respiratory patient into one of three buckets first: airflow problem (asthma, COPD — air cannot get out), perfusion problem (PE — blood cannot get through), or mass problem (cancer — something is taking up space). The bucket tells you the priority before you know a single lab value.

1 · Lung Cancer Framework — Risk Factors 🚬

Major risk factors

• Smoking — the single biggest one, responsible for the large majority of cases. Carcinogens in tobacco smoke cause repeated DNA damage in the bronchial lining, and the damaged cells eventually stop repairing correctly. Risk is measured in pack-years (packs per day × years smoked) and starts falling — but never back to zero — after quitting.
• Secondhand smoke exposure — a nonsmoker living or working with a smoker inhales the same carcinogens. This is why "never smoker" does not mean "no risk."
• Environmental exposures — radon (the #1 cause in nonsmokers — odorless gas that seeps into basements), asbestos (multiplies smoking risk enormously; also causes mesothelioma), arsenic, diesel exhaust, air pollution, and occupational dusts.
• Advanced age — most diagnoses happen after age 65. Cell damage is cumulative, and decades of exposure are what it takes.
• Family history — a first-degree relative with lung cancer raises risk independently of smoking, suggesting inherited susceptibility to carcinogen damage.

Clinical Judgment Question — Why is lung cancer often diagnosed late?

Because the lung tissue itself has no pain receptors and the early symptoms look exactly like ordinary smoker's cough or bronchitis. A tumor can grow for a long time in a large, air-filled organ before it blocks enough airway or presses on enough structure to be noticed — and by then it has often spread. Patients (and clinicians) tend to blame the chronic cough, fatigue and weight loss on smoking or aging, so the workup gets delayed.

Screening that helps: annual low-dose CT for adults roughly 50–80 years old with a 20+ pack-year history who currently smoke or quit within the last 15 years. Chest X-ray is not recommended as a screening tool — it misses small tumors.

1a · Expected Manifestations 🔍

• Chronic cough — a cough that is new, or that has changed in a long-time smoker. The tumor irritates the airway lining. "Changed" is the word that matters on an exam.
• Hemoptysis — blood in the sputum, from the tumor eroding into airway blood vessels.
• Weight loss — unintentional loss with anorexia; tumors are metabolically expensive and release cytokines that drive cachexia. A classic late red flag.
• Fatigue — from anemia, the metabolic demand of the tumor, and poor gas exchange.
• Recurrent respiratory infections — the same pneumonia in the same lobe over and over. A mass partially blocks a bronchus, secretions pool behind it, and bacteria grow. Repeat pneumonia in one spot should always raise suspicion.
• Dyspnea — airway obstruction, pleural effusion, or loss of functioning lung tissue.
• Chest pain — usually dull and persistent; means the tumor has reached the pleura, chest wall, or ribs (structures that do have pain fibers).

Which finding concerns you most and why?

Hemoptysis — and if the patient is actively bleeding a large volume, it is an airway emergency, not just a worrying symptom. Blood in the airway can obstruct ventilation before it ever causes a hemodynamic problem, so the person drowns before they bleed out. It also signals that the tumor has invaded vasculature. Position the patient with the bleeding side down, give oxygen, suction, and get help.
On a stable patient, the finding that most changes your suspicion is new hemoptysis plus unintentional weight loss — that combination is cancer until proven otherwise.

Also know the "late/spread" clues: hoarseness (recurrent laryngeal nerve), face and arm swelling with distended neck veins (superior vena cava syndrome — an oncologic emergency), dysphagia, bone pain, new neuro deficits, and clubbing of the fingers.

1b · Diagnostics Framework 🧪

Imaging finds it. Only biopsy names it.

1c · Bronchoscopy Framework 🔦

Before the Procedure — nursing responsibilities

• Verify consent — the provider obtains informed consent; the nurse confirms it is signed, dated, and that the patient can explain the procedure in their own words. Consent must be signed before sedation is given.
• NPO status — usually NPO 4–8 hours beforehand (commonly "nothing after midnight"). Also hold/clarify anticoagulants, check coagulation labs and platelets, remove dentures, and establish IV access.
• Patient education — explain that they will get moderate sedation and a numbing spray, that a sore throat and hoarseness afterward are normal, that blood-streaked sputum after a biopsy is expected, and that they will need a ride home.

Why is NPO status important?

To prevent aspiration. The patient receives sedation and a topical anesthetic sprayed on the throat, both of which knock out the gag and cough reflexes that normally keep stomach contents out of the lungs. Food or fluid in the stomach can be regurgitated and inhaled — and aspiration into a lung that is already compromised is exactly what you cannot afford. An empty stomach also gives a clearer view and less vomiting risk.

After the Procedure — priority assessments

• Respiratory status — rate, effort, breath sounds, and stridor. Laryngeal edema or laryngospasm from the scope can close the airway. Stridor, drooling, or a rising respiratory rate = call for help immediately.
• Gag reflex — check with a tongue blade against the back of the throat before anything goes in the mouth — including ice chips. Usually returns in 1–2 hours.
• Bleeding — a small amount of blood-streaked sputum after biopsy is expected; frank red blood, or more than about 30 mL, is not — report it.
• Oxygenation — continuous pulse oximetry, supplemental O₂ as ordered, and semi-Fowler's position. Also watch for a pneumothorax after transbronchial biopsy and for fever in the first 24 hours.

Why must the gag reflex return before eating?

Because the gag reflex is the body's mechanical guard against aspiration, and the topical anesthetic deliberately turns it off. Without it, food or fluid slides past the larynx and into the trachea without the patient ever coughing or feeling it — a "silent" aspiration. Confirm the gag is intact first, then start with sips of water, then advance.

Thoracoscopy Framework — Potential Complications

• Bleeding — the pleura and lung are highly vascular. Watch for rising heart rate, falling blood pressure, and chest tube drainage >100 mL/hr or bright red output.
• Pneumonia — post-op pain makes patients breathe shallowly and avoid coughing, so secretions pool. Prevent it: pain control, incentive spirometry, splinted coughing, early ambulation.
• Pneumothorax — the pleural space was entered, so air can remain or leak in and collapse the lung. This is why a chest tube usually stays in until the lung re-expands on X-ray.

What assessment findings might indicate a pneumothorax?

Sudden sharp chest pain and dyspnea with absent or diminished breath sounds on the affected side. Add: hyperresonance on percussion, unequal chest rise, tachypnea, tachycardia, falling SpO₂, and restlessness/anxiety.
If it becomes a tension pneumothorax: tracheal deviation AWAY from the affected side, distended neck veins, hypotension, and severe distress — that is a medical emergency requiring immediate needle decompression, not a call-back-later finding.

Chest tube quick rules: gentle bubbling in the water seal on exhalation = expected air leak; continuous bubbling = leak in the system, check connections. Tidaling (fluid moving with breathing) = system working. No tidaling = lung re-expanded or tube blocked. Never clamp a chest tube for more than a moment and never routinely milk or strip it.

1d · Lung Cancer Management 🩺

• Surgery — wedge resection, lobectomy (one lobe) or pneumonectomy (whole lung). The only potentially curative option, and only for non-small cell cancer caught early enough that the patient's lung function can survive losing tissue.
• Radiation — shrinks the tumor before surgery, cleans up after it, or relieves obstruction and bone pain. Teach skin care over the treatment field, expect fatigue, and watch for radiation pneumonitis (dry cough, dyspnea, fever weeks later).
• Chemotherapy — the mainstay for small cell cancer, which is nearly always spread by diagnosis. Nursing focus is myelosuppression — infection risk from neutropenia, bleeding from thrombocytopenia, fatigue from anemia — plus nausea and mucositis. A fever in a neutropenic patient is an emergency.
• Immunotherapy — checkpoint inhibitors that release the brakes on the patient's own T cells. Side effects are autoimmune, not classic chemo effects: colitis, pneumonitis, hepatitis, thyroid and adrenal problems. New dyspnea or persistent diarrhea must be reported.
• Palliative care — symptom control — pain, dyspnea, effusion drainage — provided alongside active treatment at any stage. It is not the same as hospice, and it is not giving up.

Nursing Priority — what concerns arise after a lung resection?

Priority is gas exchange and the chest drainage system, because the remaining lung is now doing all the work. Specifically:
• Respiratory: SpO₂, breath sounds bilaterally, respiratory rate and effort; semi-Fowler's; incentive spirometry and splinted coughing every hour while awake.
• Chest tube (after lobectomy): assess drainage volume and color, water seal, air leak, and insertion site for subcutaneous emphysema (crackling under the skin).
• Hemorrhage: drainage >100 mL/hr, tachycardia, hypotension.
• Pain: untreated thoracotomy pain leads directly to splinting → atelectasis → pneumonia. Medicate before deep breathing exercises.
• Arrhythmias: atrial fibrillation is common after thoracic surgery.
• After a pneumonectomy specifically: there is usually no chest tube (or a clamped one) because the empty space is meant to fill with fluid. Position on the back or the operative side so the remaining lung can fully expand, never fully on the unoperated side. Keep IV fluids conservative — the one remaining lung floods easily — and report tracheal deviation, which signals mediastinal shift.

2 · Pulmonary Embolism Framework — Pathophysiology 🩸

Complete the flow:

PE is a perfusion problem wearing a breathing problem's clothes. The alveoli are open and full of air — there is simply no blood arriving to pick the oxygen up. That is why giving oxygen alone often does not fix the SpO₂.

Risk Factors — check the ones that increase clot formation

Every one of these maps onto Virchow's triad: stasis of blood, hypercoagulability, and endothelial (vessel wall) injury. If a risk factor hits one of those three, it counts.

• Surgery — ✅ Yes — hits all three: immobility on the table and after (stasis), tissue trauma (vessel injury), and a post-op inflammatory clotting surge. Orthopedic hip and knee surgery is the highest-risk of all.
• Smoking — ✅ Yes — damages the endothelial lining and increases platelet stickiness and fibrinogen. Combined with oral contraceptives the risk multiplies rather than adds.
• Obesity — ✅ Yes — venous stasis in the legs, chronic low-grade inflammation, and reduced mobility.
• Pregnancy — ✅ Yes — estrogen raises clotting factors (hypercoagulability by design, to survive delivery) and the enlarging uterus compresses the iliac veins (stasis). Risk stays elevated into the postpartum period.
• Immobility — ✅ Yes — the purest form of stasis. Bedrest, casts, long flights, long car rides. The calf muscle pump is what moves venous blood; stop walking and the blood sits.
• Cancer — ✅ Yes — tumors release procoagulant substances, and treatment adds central lines and immobility. Malignancy is one of the strongest hypercoagulable states.
• Oral contraceptives — ✅ Yes — estrogen-containing contraceptives increase circulating clotting factors. This is why the teaching point "do not smoke on the pill" exists.
• Atrial fibrillation — ✅ Yes, it does cause clots — blood pools in the quivering atrium and clots form. But know the nuance: an a-fib clot forms in the LEFT atrium, so it exits into the systemic arteries and usually causes a stroke, not a PE. PE comes from the venous side. If a question asks specifically what causes a PE, a-fib is the weaker answer; if it asks what causes clots, it counts.

2b · Clinical Manifestations & Recognizing Cues 🚨

Classic PE findings

• Sudden dyspnea — the hallmark. Abrupt is the key word — the patient can often name the minute it started.
• Chest pain — sharp and pleuritic — it gets worse with a deep breath, because the infarcted lung segment irritates the pleura. That is different from the crushing, radiating pressure of an MI.
• Tachycardia — the heart speeds up to compensate for the blocked pulmonary circulation and the falling cardiac output. Often the earliest objective sign.
• Anxiety — a sense of impending doom. Do not dismiss it as psychological — it is an early sign of cerebral hypoxia.
• Hemoptysis — blood-streaked sputum from pulmonary infarction; a later, less common finding.

Also: tachypnea, low-grade fever, restlessness, cough, hypoxemia, and (with a massive PE) hypotension, JVD, cyanosis and syncope. ABG early on shows respiratory alkalosis with hypoxemia — the patient is blowing off CO₂ from hyperventilating.

Why does a PE cause sudden shortness of breath?

Because the blockage is mechanical and instantaneous — blood flow to that part of the lung stops the second the clot wedges in. That region keeps receiving air but gets no blood, so it becomes wasted ventilation (dead space); meanwhile the blood that is still flowing gets crowded into the remaining lung, so it cannot fully oxygenate. The lung also releases mediators that cause reflex bronchoconstriction and reduce surfactant, and the sudden rise in pulmonary vascular resistance strains the right ventricle. Result: severe hypoxemia and air hunger in a patient who was fine ten minutes ago.

Recognizing Cues Framework

Patient has: recent hip replacement · obesity · smoking history · sudden chest pain · hemoptysis

What is your priority hypothesis?

Pulmonary embolism. Three strong risk factors (major orthopedic surgery with immobility, obesity, smoking) plus the classic sudden pleuritic chest pain and hemoptysis is the textbook picture. Hip and knee replacement is the single highest-risk surgery for DVT/PE, and the clot usually announces itself in the first days to weeks after the operation. Treat this as PE until imaging says otherwise — do not wait for confirmation to act.

What data should be collected immediately?

• Oxygen saturation — ✅ Yes, first. It is instant, noninvasive, and directly measures the threatened function. Hypoxia drives the entire response.
• Respiratory rate — ✅ Yes. Tachypnea is one of the most sensitive early signs and needs no equipment at all.
• Heart rhythm — ✅ Yes. Tachycardia is expected; new right-heart strain patterns or a new arrhythmia signal a large, hemodynamically significant PE.
• Blood pressure — ✅ Yes. Hypotension is the line between a PE and a massive PE — it is what makes the patient a candidate for thrombolytics.
• Lung sounds — ✅ Yes, but understand what they will tell you: lung sounds are often clear in PE, because the problem is on the blood side, not the air side. You listen mainly to rule out pneumothorax, pneumonia and pulmonary edema — clear lungs plus severe hypoxia actually strengthens the PE hypothesis.

Why?

Because all five together tell you how much of the pulmonary circulation is blocked and whether the patient is still compensating. SpO₂ and respiratory rate size up the gas-exchange failure; heart rate, rhythm and blood pressure size up whether the right ventricle is losing the fight. Every one of them can be obtained in under two minutes at the bedside without waiting on a lab or radiology — and that speed is the whole point, because PE kills within the first hour.

While you assess — do these: stay with the patient, raise the head of bed to high-Fowler's, apply oxygen, call the provider/rapid response, and keep IV access. Do not leave the patient alone and do not ambulate them.

2c · PE Diagnostics Framework 🧪

Supporting studies: ABG (hypoxemia with respiratory alkalosis early), ECG (sinus tachycardia is most common; right-heart strain patterns in a large PE), chest X-ray (usually normal — its job is to rule out the other causes), venous duplex ultrasound of the legs to find the source DVT, and troponin/BNP to gauge right-ventricular strain.

NCLEX Connection — Why should metformin be held before CT angiography?

Because IV contrast can injure the kidneys, and if the kidneys stop clearing metformin it accumulates and causes lactic acidosis — which can be fatal. Metformin does not harm the kidney itself; the contrast does. The danger is the combination. Standard practice is to hold metformin at the time of the study and for 48 hours after, then restart only once kidney function has been rechecked and is stable. Also hydrate the patient before and after to protect the kidneys.

Watch for lactic acidosis: hyperventilation/Kussmaul breathing, muscle pain, unusual fatigue, abdominal pain, hypotension.

2d · PE Management Framework — Anticoagulation 💊

Also part of management: oxygen and high-Fowler's positioning, IV access, hemodynamic monitoring, pain control, and an IVC filter for patients who cannot receive anticoagulants or who keep clotting despite them. Newer oral anticoagulants (apixaban, rivaroxaban) are increasingly used instead of warfarin and need no INR monitoring.

Nursing Priority — the MOST important assessment after anticoagulants are started

Assess for bleeding — and neurologic status is the piece that must not be missed, because intracranial hemorrhage is the complication that kills. Anticoagulants do not distinguish between the clot you want gone and the clot holding a small vessel closed.
• Neuro: new headache, confusion, change in level of consciousness, unequal pupils, one-sided weakness → suspect bleeding in the brain and act immediately.
• Overt bleeding: gums, nose, IV sites, hematuria, bloody or tarry stools, hematemesis, unexplained bruising.
• Occult bleeding: falling H&H, new abdominal or flank/back pain, tachycardia and hypotension with no visible source.
• Labs: aPTT for heparin, INR for warfarin, platelets for HIT, H&H for blood loss.
Safety teaching: electric razor, soft toothbrush, no contact sports, no NSAIDs or aspirin unless prescribed, medical alert ID, report falls even without visible injury.

2e · Patient Teaching Framework — why do we teach… ✅

• Smoking cessation? — Because nicotine and tobacco smoke injure the vessel lining and make blood stickier — damaged endothelium plus increased platelet aggregation and fibrinogen is two-thirds of Virchow's triad in one habit. Risk is multiplied, not just added, when combined with estrogen contraceptives.
• Compression stockings? — Because graduated external pressure squeezes the superficial veins and pushes blood back toward the heart instead of letting it pool in the calf — it attacks stasis directly. Apply them in the morning before getting out of bed while the legs are least swollen, make sure they are not rolled or bunched (a rolled stocking becomes a tourniquet), and remove and check the skin daily.
• Frequent walking? — Because the calf muscles are the pump that moves venous blood out of the legs — walking is the single most effective mechanical clot prevention there is. Deep veins have no pump of their own; they depend on muscle contraction. For patients who cannot walk (long flights, post-op bedrest), teach ankle pumps and leg exercises hourly. Never massage or rub a leg suspected of DVT — it can dislodge the clot.
• Hydration? — Because dehydration concentrates the blood, and thick, sluggish blood clots more easily. Adequate fluids keep viscosity and flow normal. This matters most in exactly the situations that already cause stasis: post-op, illness with fever, and long travel.

3 · COPD Framework — Big Picture 🫁

COPD causes… leading to… leading to…

Understand air trapping — it explains almost every COPD finding ⭐

Exhalation is normally passive, powered by the elastic recoil of the lung. In COPD that recoil is destroyed and the small airways lose their structural support, so they collapse partway through exhalation and shut the air in behind them.

• Residual volume rises → the chest sits permanently over-inflated → barrel chest, and each new breath starts from an already-full lung, so tidal volume shrinks.
• The diaphragm flattens → a flat diaphragm is a mechanically weak diaphragm, so accessory muscles take over and the work of breathing skyrockets — this is why COPD patients lose weight.
• CO₂ cannot get out → chronic hypercapnia, which the kidneys compensate for by retaining bicarbonate — giving the classic compensated respiratory acidosis on ABG.
• Alveoli over-stretch and rupture → blebs and bullae form, and one can burst → spontaneous pneumothorax.

COPD is not trouble getting air in. It is trouble getting air out.

3b · Chronic Bronchitis vs Emphysema 🔵🌸

Chronic Bronchitis — think "Blue Bloater"

What is happening in the lungs?

The airways themselves are chronically inflamed and drowning in mucus. Long-term irritation makes the mucus-producing glands enlarge and multiply while the cilia that would normally sweep that mucus out are destroyed — so thick secretions sit in the bronchi, narrow them, and block airflow. Clinically it is defined as a productive cough for at least 3 months a year, 2 years in a row. The mucus plugs also make the lungs a perfect culture medium, which is why these patients get infection after infection.
Why "blue bloater": mucus-blocked airways mean poor gas exchange → hypoxemia and cyanosis (blue) → chronic hypoxia drives pulmonary vasoconstriction → right heart failure → peripheral edema, JVD and weight gain (bloated). Chronic hypoxia also stimulates erythropoietin, so these patients often have polycythemia.

• Productive cough — the defining feature; worst in the morning when a night's worth of secretions has pooled.
• Mucus production — thick and copious, from hypertrophied goblet cells and mucous glands.
• Hypoxia — air cannot reach alveoli past the mucus, so ventilation and perfusion do not match → cyanosis, and eventually cor pulmonale.

Emphysema — think "Pink Puffer"

What is happening to the alveoli?

The alveolar walls are being destroyed, so many small sacs merge into a few large floppy ones. That does two things at once: it wipes out the surface area available for gas exchange, and it destroys the elastic recoil and the tethering that holds small airways open — so the airways collapse on exhalation and trap air. The pulmonary capillary bed is destroyed along with the walls. Smoking is the usual cause; in a young non-smoker with emphysema, think alpha-1 antitrypsin deficiency.
Why "pink puffer": these patients keep their oxygen levels near-normal for a long time by working extremely hard to breathe — "puffing" through pursed lips — so they stay pink but become exhausted and thin.

• Barrel chest — years of trapped air permanently expand the rib cage; the anteroposterior diameter approaches the side-to-side diameter (about 1:1 instead of the normal 1:2).
• Dyspnea — the main complaint, and it is present at rest in advanced disease. Cough is minimal — the opposite of bronchitis.
• Thin extremities — muscle wasting and weight loss, because breathing itself burns an enormous number of calories and eating makes them breathless. Teach small, frequent, high-calorie, high-protein meals and rest before eating.
• Pursed-lip breathing — a self-taught compensation — see the mechanism below.

Reality check: most patients have features of both. The blue bloater / pink puffer split is a teaching tool for recognizing the extremes, not two separate diseases.

3c · Assessment Framework — why each finding happens 🔍

Why does pursed-lip breathing help COPD patients? ⭐

Because it keeps the floppy small airways from collapsing during exhalation, which is exactly the defect in COPD. Breathing out against partially closed lips raises pressure inside the airway above the pressure of the surrounding lung tissue, so the airway stays open long enough to empty. Less trapped air means the next breath starts from a lower, more efficient lung volume.
How to teach it: inhale slowly through the nose for about 2 counts, then exhale gently through pursed lips (like blowing out a candle or whistling) for about 4 counts — exhalation roughly twice as long as inhalation. Do not force or blow hard. Use it during activity, stair climbing, and any episode of breathlessness.
Pair it with diaphragmatic (belly) breathing and with the tripod position for the most relief.

3d · COPD Diagnostics & Complications 🧪

COPD Complications Framework

3e · Acute COPD Exacerbation Framework 🚑

Patient arrives with: dyspnea · increased sputum · low SpO₂

What should the nurse do first?

Sit the patient upright — high-Fowler's or leaning forward on the overbed table — and apply controlled low-flow oxygen titrated to an SpO₂ of 88–92%, then give the prescribed short-acting bronchodilator. Positioning costs nothing, takes two seconds, and immediately improves ventilation; oxygen treats the hypoxemia that is the actual threat to life. Both address B in ABC before anything else.
Then, in order: nebulized albuterol (+ ipratropium) → systemic corticosteroid → antibiotics if the sputum has changed color/increased (infection is the usual trigger) → ABG and chest X-ray → continuous monitoring, staying with the patient → escalate to BiPAP if the CO₂ keeps climbing and the pH keeps falling.

Why is positioning important?

Because sitting upright lets gravity pull the abdominal organs downward and away from the diaphragm, so the lungs have room to expand. Lying flat pushes the abdominal contents up against an already flattened, weakened diaphragm and shrinks the space available for air — the exact opposite of what a hyperinflated chest needs. Upright and leaning forward also anchors the shoulder girdle so the accessory muscles can help, and it improves the mechanics of coughing so secretions actually clear. Position first — it is the fastest intervention you own.

Also teach for home: call the provider for increased dyspnea at rest, a change in sputum color or amount, fever, or needing the rescue inhaler far more often — catching an exacerbation early keeps it out of the ICU.

3f · Oxygen Therapy Framework — the 88–92% rule ⭐

Target oxygen saturation

Target SpO₂: 88–92% for a patient with COPD who retains CO₂ (corresponding to a PaO₂ of roughly 60–70 mmHg). Start low — 1–3 L/min by nasal cannula or 24–28% by Venturi mask — and titrate. Note the contrast: for most other patients the goal is >94%; for COPD, more is not better.

Why don't we aggressively administer oxygen to every COPD patient? ⭐

Because in a chronic CO₂ retainer, flooding the patient with oxygen can make them stop breathing adequately and drive the CO₂ even higher — producing drowsiness, confusion, and respiratory arrest. Three mechanisms, and exams may ask for any of them:
1. Loss of the hypoxic drive (the classic nursing-exam answer). Normally a rising CO₂ is what tells the brain to breathe. In someone chronically hypercapnic, the brain has stopped responding to CO₂ and now uses a low oxygen level as its stimulus to breathe. Erase the low oxygen with high-flow O₂ and you erase the trigger — the respiratory rate and depth fall.
2. Worsened V̇/Q̇ mismatch. The lung normally shunts blood away from poorly ventilated areas by constricting those vessels. High oxygen releases that constriction, so blood floods back into areas that cannot exchange gas — increasing dead space and CO₂.
3. The Haldane effect. Hemoglobin loaded with oxygen holds less CO₂, so CO₂ is dumped into the plasma and the measured PaCO₂ rises.
What this does NOT mean: never withhold oxygen from a hypoxic patient who is in respiratory distress. Hypoxia kills faster than hypercapnia. Give oxygen — give it controlled and titrated to 88–92%, and monitor level of consciousness and respiratory rate closely.

The sign that oxygen is too high: the patient gets sleepy and calm, and the respiratory rate drops. That is CO₂ narcosis, not improvement.

Home oxygen safety teaching: no smoking or open flame in the room, no petroleum-based products around the face, keep the tubing untangled, use water-based lubricant for dry nares, and never change the flow rate without an order.

4 · Asthma Framework — Pathophysiology 🌬️

Complete the flow:

Three things narrow the asthmatic airway: muscle spasm, swelling, and mucus. That is why one drug is never enough — a bronchodilator only fixes the muscle. The steroid is what fixes the swelling, and it is the reason a controller inhaler must be taken every day even when the patient feels fine.

Risk Factors — circle all that apply

• Allergies — ✅ Yes. Atopy (eczema, allergic rhinitis, food and environmental allergies) is the strongest predictor of childhood asthma — the same IgE-mediated response that causes hives in the skin causes bronchospasm in the lungs.
• Smoking — ✅ Yes — active and secondhand. Smoke inflames the airway, paralyzes the cilia, and makes the airway permanently more twitchy. Secondhand exposure in childhood is a major cause.
• GERD — ✅ Yes. Refluxed acid microaspirated into the airway irritates it directly, and acid in the esophagus also triggers a vagal reflex that causes bronchoconstriction. Asthma that is worse at night should make you think about reflux — treat the GERD and the asthma often improves.
• Family history — ✅ Yes. Asthma and atopy run strongly in families; a parent with asthma substantially raises a child's risk.
• Environmental irritants — ✅ Yes — dust mites, cockroach and mouse antigen, pet dander, mold, pollen, air pollution, occupational chemicals and fumes.

All five apply. The item to slow down on is GERD — students often skip it because it does not sound respiratory.

Trigger Avoidance Framework

4b · Asthma Manifestations & Pulmonary Function Testing 🔍

Expected findings

• Wheezing — a high-pitched whistle, expiratory first, then inspiratory as obstruction worsens.
• Dyspnea — air hunger and a prolonged expiratory phase; the patient cannot get air out.
• Chest tightness — the sensation of the bronchial smooth muscle contracting and the chest staying hyperinflated. Patients often describe it as a band or a weight.
• Cough — often dry and worse at night or early morning. Cough-variant asthma may present with cough as the only symptom.
• Tachycardia — from hypoxia, from the sympathetic stress response, and from the beta-agonist rescue inhaler itself. A pulse rising alongside worsening work of breathing is a warning sign.

Add: tachypnea, accessory muscle use and retractions, tripod position, inability to speak full sentences, anxiety and restlessness, and diaphoresis.

Why does wheezing occur?

Because air is being forced through airways that are too narrow, and the turbulence makes the airway walls vibrate — like air squeezing through a pinched straw. The narrowing comes from all three asthma changes at once: bronchospasm, mucosal swelling, and mucus. It is loudest on exhalation because airways naturally narrow further as the chest deflates and intrathoracic pressure rises.
Critical: wheezing that suddenly disappears in a patient who is still struggling is NOT improvement. A "silent chest" means airflow has dropped too low to make any sound — that is impending respiratory arrest. Get help immediately.

Pulmonary Function Testing Framework — Purpose

To measure how much air the patient can move and how fast, and — the part that makes the diagnosis — to prove the obstruction is reversible. Spirometry is done, a bronchodilator is given, and spirometry is repeated: an increase in FEV₁ of at least 12% and 200 mL confirms asthma. A COPD patient's numbers barely budge. PFTs also establish a baseline, grade severity, and track response to therapy over time. A methacholine challenge can be used when spirometry is normal but asthma is still suspected.

Peak flow meter — the home version she must know 📈

• Green zone: 80–100% of personal best — good control; continue the daily controller medication.
• Yellow zone: 50–79% — caution — the airway is narrowing. Use the rescue inhaler and follow the written asthma action plan; call the provider if the readings stay here.
• Red zone: below 50% — Medical emergency — use the rescue inhaler immediately and get emergency care.

Teach: measure at the same time each day, stand up, take the best of three attempts, and establish "personal best" while well. A falling peak flow drops before the patient feels much worse — that early warning is the entire value of the device.

4c · 🚨 Asthma Complications — Status Asthmaticus

What is it?

A severe, prolonged asthma attack that does NOT respond to the usual rescue treatment — repeated bronchodilators and corticosteroids do not break it. The inflammation, bronchospasm and mucus plugging feed each other, so every breath adds more trapped air to a chest that is already full. It is the extreme end of an exacerbation, and it can develop over hours or over days.

Why is it life threatening?

Because the patient cannot exhale, so air stacks up until the lungs are so hyperinflated that ventilation essentially stops — and the respiratory muscles exhaust themselves trying. The chain:
• Progressive air trapping → the lungs cannot empty → each breath moves less and less air.
• Muscle fatigue → the work of breathing becomes unsustainable → ventilation collapses.
• Severe hypoxemia + rising CO₂ → respiratory acidosis → confusion, then loss of consciousness.
• Rising intrathoracic pressure → reduced venous return and cardiac output → hypotension; risk of pneumothorax.
• End point: respiratory arrest, then cardiac arrest.

⚠️ The findings that mean "this patient is about to arrest"

• Silent chest — wheezing stops but the patient is still in distress. No airflow = no sound. This is the classic exam answer for "which finding requires immediate intervention."
• A "normal" or rising PaCO₂ on ABG. An asthmatic in distress should be hyperventilating and blowing OFF CO₂ — so a low PaCO₂ is expected. A PaCO₂ that has risen to normal means the patient is tiring and can no longer move air.
• Decreasing level of consciousness, drowsiness, or a patient who suddenly stops fighting. Calm is not improvement here.
• Inability to speak more than one or two words, cyanosis, bradycardia, or a falling respiratory rate in a still-obstructed patient.

Loud wheezing means air is still moving. A quiet chest in a struggling asthmatic is the emergency.

Emergency Interventions — priority treatments

• Oxygen — high-flow, humidified, titrated to keep SpO₂ >94% (asthma is not COPD — there is no 88–92% restriction here). Sit the patient upright.
• Albuterol — short-acting beta₂ agonist by nebulizer, often given continuously or back-to-back in status asthmaticus. Opens the airway within minutes.
• Ipratropium — anticholinergic added to albuterol in the emergency setting; it blocks the parasympathetic constriction pathway, so the two drugs open the airway by two different mechanisms and work better together than either alone.
• Corticosteroids — IV methylprednisolone or oral prednisone — given early even though they take 4–6 hours to work, because they treat the airway swelling that the bronchodilators cannot touch, and that swelling is what makes the attack keep coming back.

Also: IV access and fluids (these patients are dehydrated from the work of breathing), continuous pulse oximetry and cardiac monitoring, ABGs, magnesium sulfate IV as a smooth-muscle relaxant in severe cases, and preparation for intubation at the bedside. Do not give sedatives to an asthmatic in distress — they blunt the respiratory drive. And never leave the patient alone.

Why is albuterol usually given first?

Because it is the fastest — it relaxes the bronchial smooth muscle within about 5 minutes, so it directly relieves the bronchospasm that is choking the patient right now. There is a second reason that matters just as much: opening the airway first is what allows the other drugs and the oxygen to actually reach the lower airways. Give a steroid into a clamped-shut airway and much of it never gets there. Corticosteroids are essential but take hours; albuterol buys the time for them to work.

Inhaler Teaching Framework

After using an inhaled corticosteroid, the patient should…

Rinse the mouth with water and spit it out (and brush the teeth) after every dose.

Why?

Because steroid that settles on the mouth and throat suppresses the local immune defenses and lets Candida overgrow — oral thrush. Rinsing washes the leftover drug off the mucosa before it can do that. It also prevents hoarseness/dysphonia and a dry irritated throat. Spitting rather than swallowing keeps the extra drug from being absorbed systemically. Using a spacer with the MDI does the same job from the other end — it keeps large droplets from ever landing in the mouth and gets more drug into the lungs.

MDI technique to teach: shake → exhale fully → seal lips (or use spacer) → press and inhale slowly and deeply → hold breath about 10 seconds → wait about 1 minute between puffs of the same drug. Rescue vs controller: the rescue inhaler (albuterol) is for symptoms right now and should be carried at all times; the controller (inhaled corticosteroid, montelukast) is taken daily whether or not she feels symptoms — it prevents attacks and does nothing during one. Needing the rescue inhaler more than 2 days a week means the asthma is NOT controlled — report it, do not just refill it.

4d · Asthma Medication Framework 💊

Also know: long-acting beta agonists (salmeterol) are controllers that must never be used alone or as a rescue inhaler — only combined with an inhaled corticosteroid. Theophylline has a narrow therapeutic range (10–20 mcg/mL); watch for nausea, tachycardia and seizures, and remember caffeine adds to the toxicity. Omalizumab and other biologics are for severe allergic asthma.

4e · Asthma Case Study Framework 🧠

Patient presents with: wheezing · tachypnea · short phrases · tripod position · chest tightness

What cues suggest respiratory distress?

All five — and two of them tell you it is severe.
• Speaking in short phrases — ⭐ the strongest cue. How many words a patient can say in one breath is a bedside measure of how much air they can move. Full sentences = mild. Phrases = moderate–severe. Single words = severe. Cannot speak = emergency.
• Tripod position — the patient is instinctively recruiting accessory muscles; nobody sits like that unless they need to.
• Tachypnea — increased work of breathing and an attempt to compensate for hypoxemia.
• Wheezing — confirms narrowed airways with air still moving. Reassuring in a grim way: it is worse when it stops.
• Chest tightness — the subjective marker of bronchospasm and hyperinflation.
Also look for: accessory muscle use and retractions, nasal flaring, restlessness/anxiety, falling SpO₂, and a peak flow below 50% of personal best.

What is your priority nursing action?

Stay with the patient, sit them upright, and administer oxygen — then give the prescribed short-acting bronchodilator (albuterol nebulizer). Priority is airway and breathing: the patient is hypoxic and obstructed right now, and oxygen plus a bronchodilator are the two interventions that reverse the immediate threat. Assessment and treatment happen simultaneously here — you do not complete a head-to-toe on a patient in respiratory distress. Never leave a patient in acute respiratory distress alone, and never lay them flat.

What interventions should occur FIRST? (in order)

Once stable, teach: identify and avoid triggers, use the peak flow meter and the written action plan, carry the rescue inhaler at all times, take the controller daily, correct MDI/spacer technique, rinse after steroids, and get the annual flu vaccine.

5 · Asthma vs COPD — the two that get confused ⭐

Both obstruct airflow and both wheeze. The word that separates them is "reversible."

One sentence: asthma is an airway that closes and reopens; COPD is an airway that is permanently damaged and cannot empty.

6 · Module Wrap-Up Framework 🧭

For every respiratory disorder ask… (this is the framework the course wants you to leave the module with)

That framework will help you move beyond memorization and start thinking like a nurse.

Practice Questions — clinical judgment 🧠

⭐ Must-Not-Forget Strip

• 1. COPD SpO₂ target is 88–92%. Higher saturations can knock out the hypoxic drive, worsen V/Q mismatch and raise CO₂. But never withhold oxygen from a hypoxic patient — give it controlled and titrated. If a COPD patient gets sleepy and calm, suspect CO₂ narcosis, not improvement.
• 2. COPD is an exhalation problem. Air trapping → barrel chest, flattened diaphragm, hypercapnia, blebs. Pursed-lip breathing splints the airways open so the lungs can empty — in 2 counts through the nose, out 4 counts through pursed lips.
• 3. A silent chest in an asthmatic is an emergency. No wheeze + still in distress = no airflow = about to arrest. Same for a PaCO₂ that rises to "normal" in an acute attack.
• 4. Status asthmaticus = a severe attack that does not respond to standard treatment. Oxygen → albuterol (fastest, opens the airway so everything else can work) → ipratropium → corticosteroid (takes 4–6 hours but treats the swelling). Never sedate; never leave the patient.
• 5. Rescue vs controller. Albuterol = rescue, carried at all times, works in minutes. Inhaled corticosteroid and montelukast = controllers, taken daily even when well, useless in an attack. If both are due: bronchodilator first, wait 5 minutes, then steroid, then rinse and spit. Needing the rescue inhaler more than 2 days a week = poor control.
• 6. PE is sudden. Sudden dyspnea + pleuritic chest pain + tachycardia + anxiety + clear lungs in a patient with a Virchow's triad risk factor (stasis, hypercoagulability, vessel injury). D-dimer rules out; CT angiography confirms. Hold metformin 48 hours after contrast — contrast-induced kidney injury → metformin accumulation → lactic acidosis.
• 7. Anticoagulants stop clots from growing; only thrombolytics dissolve them. Heparin → aPTT + platelets, antidote protamine. Warfarin → INR 2–3, antidote vitamin K, consistent green vegetable intake. The priority assessment after starting any of them is bleeding — and a new headache or change in LOC means intracranial hemorrhage.
• 8. Lung cancer is found late because lung tissue has no pain fibers and the early symptoms look like smoker's cough. Only a biopsy diagnoses it. After bronchoscopy, nothing by mouth until the gag reflex returns. After pneumonectomy, position on the back or the operative side and keep IV fluids conservative.