The Respiratory I lecture framework, worked through. Tap "Hide answers" to quiz yourself.
This is the framework page — the thinking scaffold behind Respiratory I, built around the lecture objectives. It is the companion to your Respiratory I Guided Notes: the notes hold the content, this page holds the reasoning that gets you to the right answer under time pressure. Every highlighted answer was a blank or an open prompt in the framework document.
Everything in this module comes back to ONE question: Can the patient oxygenate effectively?
If not, the lecture asks three follow-ups. Turn them into a fixed loop you run on every respiratory patient — the same loop the NCLEX is testing.
Name the broken step, not the disease. "Pneumonia" is not an answer — "the alveoli are filled with exudate so oxygen cannot cross the membrane" is. Because the broken step is what tells you which intervention actually fixes anything: a ventilation problem needs help moving air, an exchange problem needs oxygen and treatment of what is filling the alveoli.
The findings that change EARLY: respiratory rate, work of breathing, and mental status. Restlessness plus a rising rate is hypoxia until proven otherwise. Because SpO₂ and skin color are late — by the time they move, compensation has already failed.
Airway, then breathing, then everything else. Position upright, open and clear the airway, give oxygen, stay with the patient and get help. Because no drug, lab, or call works on a patient who is not moving air.
Framework rule for the whole module: Never pick "notify the provider" or "document" over an action that opens the airway or delivers oxygen — unless the airway is already secure and the answer choices contain nothing else you can do.
By the end of this lecture, I should be able to… Treat each objective as a test question. If you can say these seven answers out loud, you have the module.
Highest-yield line on this page: objectives 2 and 7 are where the exam points live — naming ventilation vs oxygenation, and picking who to see first.
When assessing a respiratory patient, I should ALWAYS look at — and for each one, know the number and what it makes you do next.
| What I look at | Normal / what I am judging | What makes me act |
|---|---|---|
| Respiratory rate | 12–20 breaths/min in an adult | <10 or >24 — and a rising rate is the single earliest objective warning of trouble |
| Respiratory depth | Even and adequate — enough tidal volume to move air, not just shuffle it | Shallow breathing — a rate of 28 with tiny breaths moves less air than a rate of 16 with normal ones |
| Respiratory effort | Quiet, relaxed, unlabored | Visible work, inability to speak a full sentence, tripod position |
| Work of breathing | Retractions, nasal flaring, grunting, pursed-lip breathing, head bobbing | Any of them — and a patient who stops working after working hard is exhausting, not improving |
| Lung sounds | Clear to auscultation in all fields, front and back, compared side to side | Stridor (emergency), absent or silent fields (worse than wheezing), new crackles |
| Oxygen saturation | 95–100%; 88–92% is the accepted target for a CO₂ retainer with COPD | <90% — because 90% saturation is roughly a PaO₂ of 60 mmHg, the edge of the cliff on the oxyhemoglobin curve |
| Skin color | Pink, warm, dry; check lips, oral mucosa, and nail beds — not just the hands | Pallor, dusky or mottled skin, cyanosis — cyanosis is late |
| Mental status / LOC | Alert, oriented, calm, cooperative | New restlessness or anxiety (early hypoxia) → confusion → somnolence (late, and ominous) |
| Accessory muscle use | None — the diaphragm should be doing the work | Sternocleidomastoid/scalene use or intercostal retractions — the patient has run out of reserve |
Framework point: two findings move first — the respiratory RATE and the MENTAL STATUS. Because the body compensates by breathing faster long before the saturation drops, and the brain complains about hypoxia before any other organ.
Never use a normal pulse ox to reassure yourself about a patient who is restless and breathing 30 times a minute. The pulse ox is the last thing to fall, and it tells you nothing at all about CO₂.
Respiratory function is really the body trying to move oxygen from the AIR into the CELLS. Five steps. Every respiratory diagnosis you will ever see is one of them failing — so learn the chain, not the list of diseases.
Ventilation = movement of air in and out of the lungs. Question to ask: Can the patient physically move air?
Answer that question with: Look and listen — is the chest rising, is air moving at the mouth, can they speak in full sentences, is the rate and depth adequate? A patient who cannot speak more than two words at a time is failing this step right now.
Examples of ventilation problems:
Poor ventilation causes: ↑CO₂ → respiratory acidosis (PaCO₂ above 45 mmHg, pH below 7.35) → headache, drowsiness, flushed warm skin, confusion, and eventually a CO₂ narcosis coma. Because CO₂ dissolves into carbonic acid — retained CO₂ IS acid.
Air must reach the alveoli for gas exchange to occur. Problems that interfere:
Result: less oxygen available for exchange. The nursing fix aimed at this step: Open and clear the passage — cough and deep breathe, incentive spirometry, hydration to thin secretions, suction, bronchodilators, early ambulation. Oxygen alone does not help air get past a plug.
Even if the lungs are functioning properly, oxygen still needs transportation. Problems:
Low hemoglobin can cause: tissue hypoxia with a normal SpO₂ and a normal PaO₂. Because the pulse ox reports the PERCENT of hemoglobin that is saturated, not how much hemoglobin exists. A hemoglobin of 6 g/dL that is 99% saturated still delivers half the oxygen of a normal patient — and in carbon monoxide poisoning the pulse ox reads falsely high, because it cannot tell carboxyhemoglobin from oxyhemoglobin.
Perfusion problems:
Respiratory problems usually involve poor air movement · blocked alveoli · impaired gas exchange · low hemoglobin · poor perfusion.
Say which of the five broke BEFORE you pick an intervention. If you cannot name the step, you cannot defend the intervention — and that is exactly what the exam rationale is testing.
| Patient | Broken step | What actually fixes it |
|---|---|---|
| Post-op, PCA morphine, RR 8, SpO₂ 88% | Step 1 — ventilation | Stop the opioid, stimulate, open the airway, support ventilation; naloxone if needed. More oxygen alone leaves the CO₂ climbing. |
| Day 2 post-op, splinting, diminished bases, low-grade fever | Step 2 — air is not reaching the alveoli (atelectasis) | Pain control so she can breathe deeply, incentive spirometry, ambulation, cough and deep breathe |
| Pneumonia, crackles, SpO₂ 87% on room air | Step 3 — diffusion across the membrane | Oxygen, antibiotics, airway clearance, position with the good lung down for perfusion |
| Hgb 6.4 g/dL after a GI bleed, SpO₂ 99%, exhausted and tachycardic | Step 4 — hemoglobin | Transfuse and stop the bleeding. Oxygen will not help — there is nothing to carry it. |
| BP 78/40, mottled knees, lactate rising, lungs clear | Step 5 — perfusion | Fluids and hemodynamic support — the problem is delivery, not the lung |
| Ventilation — "move AIR" | Oxygenation — "move OXYGEN" | |
|---|---|---|
| Main problem | CO₂ retention — hypercapnia, and the respiratory acidosis that follows | Low oxygen in the blood — hypoxemia (low PaO₂ and SpO₂) |
| The number that tells you | PaCO₂ >45 mmHg with pH <7.35 — and end-tidal CO₂ if you have it | PaO₂ <80 mmHg, SpO₂ <90% — PaCO₂ is often normal or LOW early, because they are breathing fast |
| Examples | COPD · opioid overdose · hypoventilation plus: neuromuscular disease, chest trauma, oversedation, obesity hypoventilation | Pulmonary edema · pneumonia · pulmonary embolism plus: ARDS, atelectasis, pneumothorax |
| What the patient looks like | Sleepy, headachy, flushed, slow or shallow breathing — deceptively quiet | Anxious, tachypneic, air hungry, restless — visibly working |
| What fixes it | Make them breathe: reverse the sedation, treat pain so they can breathe, BiPAP, bag-mask, intubate. Support the BREATH. | Improve exchange: oxygen, treat the pneumonia or the edema, position upright. Support the OXYGEN. |
Oxygen does not fix a ventilation problem. Because giving oxygen raises the saturation while the CO₂ keeps climbing — you have hidden your only warning sign and changed nothing about the acidosis. Never treat a sedated, slowly breathing patient by simply turning up the oxygen and walking away.
Both at once: A patient can fail both — a COPD exacerbation retains CO₂ and drops the PaO₂. When both fail, ventilation is the more urgent problem, because rising CO₂ is what puts them to sleep and stops the breathing altogether.
Low oxygen levels in the BLOOD.
Low oxygen at the TISSUE level. A patient can have normal lungs and STILL become hypoxic.
Hypoxemia is a number. Hypoxia is a patient. Hypoxemia almost always causes hypoxia if it is not corrected — but hypoxia can exist with a perfectly normal SpO₂, and that is the trap in the question.
The classic trap: Never trust a pulse ox in suspected carbon monoxide poisoning — a standard SpO₂ reads normal or high because it cannot distinguish carboxyhemoglobin from oxyhemoglobin. Give 100% oxygen by non-rebreather based on the history, not the number.
When a patient deteriorates, ask: is the problem ventilation, gas exchange, perfusion, or hemoglobin? Here is how to tell in about ten seconds at the bedside.
| Is it… | Ask | The clue that says yes | First move |
|---|---|---|---|
| Ventilation? | Are they moving air at all? | Slow or shallow breathing, sedation, no chest rise, rising CO₂, snoring respirations | Open the airway, stimulate, support the breath — bag-mask if the rate is inadequate |
| Gas exchange? | Is the membrane working? | Crackles, wheezes, low SpO₂ despite good effort, working hard and still hypoxemic | Sit upright, apply oxygen, treat the cause (diuretic for edema, antibiotic for pneumonia) |
| Perfusion? | Is blood reaching the tissue? | Hypotension, tachycardia, cool mottled extremities, delayed cap refill, low urine output, clear lungs | Fluids and circulatory support — oxygen will not reach tissue that has no blood flow |
| Hemoglobin? | Is there anything to carry it? | Pallor, bleeding, low H&H, exertional dyspnea with a normal SpO₂ | Stop the bleeding, transfuse, treat the anemia |
Framework habit: Recognize cues → analyze which of the four broke → prioritize the airway → take one action → re-assess the same finding that alarmed you. That last step is the one students skip, and it is worth points on every next-gen item.
| Early signs — act HERE | Late signs — already in trouble | |
|---|---|---|
| Findings | Restlessness · anxiety · irritability · tachypnea · tachycardia · mild hypertension · pallor · dyspnea on exertion | Confusion → somnolence → unresponsive · bradycardia · hypotension · dysrhythmias · cyanosis · cool clammy skin |
| What it means | Compensation is working — the body is buying you time. This is where an intervention still prevents everything else. | Compensation has FAILED. The patient is decompensating and needs rescue, not assessment. |
Cyanosis and bradycardia are LATE. Restlessness is the first thing you get.
Never sedate a newly restless patient before you have assessed their oxygenation. Sedating hypoxia removes the drive to breathe and turns an early sign into an arrest.
| Restrictive | Obstructive | |
|---|---|---|
| Problem | The lung or chest wall cannot EXPAND — reduced compliance or restricted volume | Air can get in but cannot get back OUT — airway narrowing and air trapping |
| Difficulty getting air… | IN | OUT |
| Examples | Pulmonary fibrosis, pneumonia, atelectasis, pleural effusion, severe obesity, kyphoscoliosis, neuromuscular disease, ascites, chest wall burns | COPD — emphysema and chronic bronchitis — asthma, bronchiectasis, cystic fibrosis |
| Expected findings | Rapid SHALLOW breathing, decreased lung volumes and compliance, dyspnea on exertion, diminished sounds, normal or high FEV₁/FVC ratio | PROLONGED expiration, wheezing, pursed-lip breathing, barrel chest and air trapping, decreased FEV₁/FVC ratio, chronic cough |
| Helpful positioning | Upright, high Fowler's, relieve whatever is pressing on the lung (drain the effusion, treat the ascites, control pain) | Upright leaning forward on a table (tripod), pursed-lip breathing to hold the small airways open on exhalation |
Restrictive = cannot fill. Obstructive = cannot empty. Restrictive patients breathe fast and small; obstructive patients breathe slow and long on the way out. That one sentence sorts most of the exam questions.
Upper respiratory infections involve: the nose · sinuses · pharynx · larynx — everything above the trachea. That location matters: the upper airway is narrow and, at the larynx, surrounded by cartilage that will not stretch, so swelling here threatens the airway far faster than the same swelling lower down.
| Manifestation | Nursing response |
|---|---|
| Nasal congestion | Humidified air, saline spray or rinse, upright positioning; topical decongestant no more than 3 days |
| Rhinorrhea | Fluids, tissues and hand hygiene, antihistamine if allergic in origin — expect it to look thicker and more colored as it resolves; color alone does not mean bacteria |
| Sore throat | Warm saline gargles, lozenges, cool fluids or ice chips, acetaminophen or ibuprofen |
| Hoarseness | Voice rest and humidification — and note the calendar, because hoarseness lasting over 2 weeks needs evaluation |
| Cough | Hydration and humidity; expectorant to loosen secretions. Do not suppress a productive cough — that cough is airway clearance |
| Fatigue | Rest, and teach that it is expected and self-limiting — typically improving within 7–10 days |
| Fever | Antipyretic, fluids to replace insensible losses; report fever that persists past 3–4 days or spikes after improvement |
Stridor (the upper airway is closing) · drooling or inability to swallow secretions · muffled "hot potato" voice · trismus (cannot open the mouth) · severe dyspnea, retractions, accessory muscle use · cyanosis · any change in LOC · neck swelling or a stiff neck with high fever · a patient sitting forward in a tripod, refusing to lie down.
Never make a patient with suspected epiglottitis or a threatened airway lie flat, and never put a tongue blade or anything else into the throat to "get a better look" — that can trigger complete obstruction. Keep them upright and calm, and get the airway team.
Concerning findings: drooling · muffled voice · difficulty swallowing · trismus. Add: severe unilateral throat pain, the uvula deviated away from the swollen side, high fever, and a patient who will not lie back.
| Complication | How the URI gets there |
|---|---|
| Airway obstruction | Swelling in a narrow, non-expanding upper airway — the emergency of this module |
| Sepsis | Bacteria from a tonsillar or sinus infection enter the bloodstream — watch for fever with tachycardia, hypotension, and confusion |
| Meningitis | Sinus infection spreads through thin bone into the CNS — stiff neck, photophobia, severe headache, high fever |
| Dysphagia | Pain and swelling make swallowing unsafe → poor intake, dehydration, and aspiration risk |
| Cellulitis | Infection spreads into surrounding soft tissue or the orbit — periorbital swelling and redness is an urgent referral |
| Rebound congestion | Rhinitis medicamentosa — topical decongestant sprays (oxymetazoline, phenylephrine) used beyond 3 days. The vessels dilate wider than before when the drug wears off, so she feels more congested and uses more spray. |
Never let a patient keep using a nasal decongestant spray "because it is the only thing that works." Three days, then stop — saline and humidity after that.
Which URI patient worries you MOST and why? Rank all five — and be able to say the reason, because the reason is the exam answer.
| Rank | Finding | Why it sits there |
|---|---|---|
| 1st | Stridor | A high-pitched sound of air forced through a narrowing UPPER airway. It is the airway announcing that it is closing — act now, do not leave the room. |
| 2nd | Drooling | The patient cannot swallow their own secretions. Obstruction is minutes to hours behind it, and aspiration is a live risk. |
| 3rd | Cyanosis | A LATE sign — oxygenation is already severely impaired by the time you can see it. Urgent, but it tells you the failure has been going on a while. |
| 4th | Confusion | Cerebral hypoxia with compensation failing. Also late — but if this patient is confused AND breathing poorly, treat as airway/breathing immediately. |
| 5th | Accessory muscle use | Real distress and real work — but the airway is still open and the patient is still compensating. Assess and intervene, just after the four above. |
Airway beats oxygenation; oxygenation beats everything else. Stridor and drooling are both airway. Cyanosis and confusion are late oxygenation. Accessory muscles mean the patient is still winning the fight — for now.
The trap: "Worst-looking" is not the same as "highest priority." A screaming patient with accessory muscle use is moving air; a quiet patient with stridor that just got softer may be moving almost none. A silent chest and a sudden calm after severe distress are emergencies, not improvements.
OSA involves repeated: collapse of the upper airway during sleep — the soft palate and tongue fall back against the pharyngeal wall, airflow stops for 10 seconds or more despite continued respiratory effort, and the patient arouses just enough to reopen it. Then it happens again, dozens of times an hour, all night.
This causes: hypoxia · hypercapnia · sympathetic stimulation.
Obesity and a large neck circumference (over about 17 in in men, 16 in in women) · male sex · age over 50 (risk in women climbs after menopause) · enlarged tonsils, a large tongue, a receding jaw or crowded oropharynx · nasal obstruction · alcohol or sedatives at bedtime · smoking · hypothyroidism · family history. The screening mnemonic is STOP-BANG: Snoring, Tired, Observed apnea, Pressure (hypertension), BMI, Age, Neck, Gender.
Loud snoring · daytime sleepiness · morning headaches · hypertension · gasping during sleep. Also: witnessed apneic pauses reported by a partner, irritability, poor concentration and memory, nocturia, decreased libido, and falling asleep at stoplights — a documented driving risk worth asking about.
Why do patients wake up exhausted? Every apneic episode ends in a micro-arousal that pulls them out of deep and REM sleep. They may be in bed 8 hours and never accumulate restorative sleep — the quantity is normal, the architecture is destroyed. Most do not remember waking at all, which is why they insist they slept fine.
How it is diagnosed: Polysomnography (sleep study) reporting the apnea–hypopnea index — roughly 5–15 events/hour is mild, 15–30 moderate, over 30 severe.
| CPAP | BiPAP | |
|---|---|---|
| Provides | ONE continuous pressure — the same on inhalation and exhalation | TWO pressures — a higher inspiratory pressure (IPAP) and a lower expiratory pressure (EPAP) |
| Purpose | Splints the airway open so it cannot collapse — it is a pneumatic stent, not a ventilator. First-line for OSA. | Splints the airway AND assists the inspiration, so it adds ventilation — it moves CO₂. Used for OSA that CPAP cannot control, and for hypercapnic failure such as a COPD exacerbation. |
| Best for | Plain obstructive sleep apnea with normal CO₂ | Patients who need help with the breath itself — CO₂ retention, obesity hypoventilation, neuromuscular weakness |
Why may patients tolerate BiPAP better? Because they exhale against a LOWER pressure. Breathing out against a single high continuous pressure feels like fighting the machine, and that sensation is the number one reason people abandon CPAP.
Never give a known OSA patient opioids or sedatives without continuous monitoring and their airway support in place. Sedation plus a collapsible airway is how the next case study starts.
Important cues: obesity · large neck circumference · PCA morphine · post-op patient · increased RR.
What the cues add up to: Three of them (obesity, neck, post-op) say undiagnosed OSA — a collapsible airway. One of them (PCA morphine) says a suppressed respiratory drive. Together they are the classic setup for opioid-induced respiratory depression in a patient who cannot compensate.
What patient complication should the nurse anticipate? Opioid-induced respiratory depression with upper airway obstruction → hypoventilation, hypercapnia, and hypoxemia. The rising respiratory rate is not reassuring — it is early compensation for a CO₂ that is already climbing, and it will fall as she tires.
| Finding | What it actually means |
|---|---|
| Snorting / gasping respirations | The airway is partially obstructed — usually the FIRST audible sign, and easy to dismiss as "just snoring" |
| Somnolence | Rising CO₂ plus opioid sedation. Sedation precedes respiratory depression — a patient too sleepy to stay awake during conversation is the warning. |
| Bradypnea | The drive is now suppressed; compensation has stopped. RR under 10–12 in an opioid patient demands action. |
| Cyanosis | Severe hypoxemia — late, and you should never have gotten here |
| Apnea | No ventilation at all — begin rescue breathing and call for help |
What is the PRIORITY problem? Impaired ventilation — an airway/breathing emergency from opioid-induced respiratory depression with airway obstruction. Not pain, not the surgery, not the saturation number. Because ventilation is the broken step, and it is the one that kills within minutes.
Never leave the room after giving naloxone because "she woke right up." Re-sedation is the expected complication, not a surprise one.
Risk factors: HTN · anticoagulants · trauma · dry mucosa · steroid sprays. Also: nose picking and forceful blowing, cocaine use, low humidity in winter, aspirin and NSAIDs, alcohol, and clotting disorders or low platelets.
Anterior vs posterior: Anterior bleeds are the common ones — visible, one-sided, and usually controlled with pressure. A posterior bleed bleeds down the throat from both sides, is more common in older adults on anticoagulants with hypertension, does not stop with pinching, and needs posterior packing or a balloon plus admission. Posterior packing itself threatens the airway — keep those patients monitored with oxygen and suction available.
The larynx does NOT stretch well. Even small swelling can become life threatening. Because it is a rigid cartilage ring around an already narrow opening — airflow resistance rises steeply as the radius shrinks, so a few millimeters of edema can cut airflow dramatically and the patient decompensates fast.
Stridor · drooling or inability to manage secretions · voice change, a muffled voice, or inability to speak · severe dyspnea with retractions and accessory muscle use · restlessness progressing to a falling LOC · tripod positioning and refusal to lie down · cyanosis (late) · a suddenly quieter chest in a patient who was loud (ominous).
Common causes: Anaphylaxis and angioedema (including ACE inhibitor angioedema), foreign body aspiration, epiglottitis, peritonsillar or retropharyngeal abscess, post-extubation edema, inhalation/burn injury, and tumor.
Nursing priority: Stay with the patient, keep them upright and calm, give oxygen, and get the airway team / call rapid response. Have suction, a bag-valve-mask, and intubation or emergency cricothyrotomy equipment at the bedside. In anaphylaxis, IM epinephrine is the first drug — antihistamines and steroids do not open an airway fast enough.
Never leave a stridorous patient alone to "go get someone," and never let anxiety build — crying and struggling increase airflow turbulence and oxygen demand, which makes the obstruction worse.
| Stridor | Wheezing | |
|---|---|---|
| Usually indicates | UPPER airway obstruction — larynx, trachea, epiglottis | LOWER airway narrowing — bronchi and bronchioles |
| When you hear it | Mostly on INSPIRATION — harsh, high-pitched, often audible from the doorway without a stethoscope, loudest over the neck | Mostly on EXPIRATION — musical whistling, heard over the lung fields with a stethoscope |
| Urgency | Emergency — the airway itself is closing. Do not step away. | Serious, but the airway is open — treat with a bronchodilator and reassess |
| Typical causes | Croup, epiglottitis, anaphylaxis, foreign body, post-extubation edema, laryngeal tumor | Asthma, COPD, bronchitis, heart failure ("cardiac asthma"), aspiration |
Stridor is a location, not a sound effect: high in the airway, on the way in, and it means now.
Risk factors: smoking · alcohol · HPV · occupational exposure. Smoking and heavy alcohol together multiply the risk rather than just adding it; occupational exposure means asbestos, wood dust, paint and chemical fumes. Also chronic laryngopharyngeal reflux and male sex over age 50.
Concerning manifestations: persistent hoarseness · dysphagia · weight loss · lump in the throat. Add: a sore throat or ear pain (referred otalgia) that will not resolve, a persistent cough, hemoptysis, a neck mass, and eventually stridor or dyspnea as the tumor narrows the airway.
Which symptom is often ignored early? Persistent hoarseness. Patients and nurses write it off as a cold, allergies, reflux, or too much talking — and it is the earliest sign because a tumor on the vocal cord changes the voice long before it blocks anything. Hoarseness lasting more than 2 weeks needs evaluation, not reassurance.
What the nurse does with that: Ask how long, ask about smoking and alcohol, look for weight loss and a neck mass, and get the referral for laryngoscopy. Screening questions are nursing work.
If a total laryngectomy happens: The patient has a permanent tracheostomy stoma and no longer breathes through the nose or mouth — so air is not warmed, humidified, or filtered, and smell and taste are reduced. Care includes humidification and stoma protection, covering the stoma when showering (no swimming ever), aspiration precautions when swallowing is relearned, an alternative communication method arranged before surgery, and rescue breathing delivered through the stoma, not the mouth. Suction and an extra tube stay at the bedside.
Always ask these four, in this order, on every respiratory patient in the room and on every respiratory question on the exam.
Airway → breathing → circulation, and within each one: fix it, then report it.
Answer: C. Restlessness
Rationale: The brain has essentially no oxygen reserve, so cerebral hypoxia shows up as restlessness, anxiety, and irritability before any other system changes. Treat new restlessness as hypoxia until you have ruled it out.
Why the others are wrong:
Answer: B. Airway obstruction
Rationale: That triad is upper airway swelling — peritonsillar abscess or epiglottitis until proven otherwise. Drooling means she cannot swallow her own saliva and a muffled voice means the pharynx is crowded. Keep her upright, NPO, suction and airway equipment ready, and escalate now.
Why the others are wrong:
Answer: C. Stridor with accessory muscle use
Rationale: Stridor is upper airway narrowing and accessory muscle use says the patient is already spending everything they have to compensate. Airway outranks every other finding, and this one can close.
Why the others are wrong:
Answer: B. Stop the PCA, stimulate the patient, and open the airway
Rationale: This is a VENTILATION failure, not an oxygenation failure — the saturation is normal only because supplemental oxygen is masking a CO₂ that is climbing. Remove the cause and support the breath.
Why the others are wrong:
Answer: A, C, D, and F.
Answer: B. Sit up, lean forward, pinch the soft part of the nose for 10–15 minutes
Rationale: Upright reduces venous pressure in the nose, forward keeps blood out of the throat, and pinching the cartilage compresses the anterior septum where nearly all nosebleeds originate.
Why the others are wrong:
Answer: C. Well-saturated hemoglobin, but not enough carriers — tissue hypoxia with a normal SpO₂
Rationale: Pulse oximetry reports the PERCENTAGE of available hemoglobin that is carrying oxygen, not the total amount of oxygen delivered. This is step 4 of the gas exchange chain — the fix is transfusion and treating the anemia, not oxygen.
Why the others are wrong:
Do not memorize diseases. Think through the patient: What clues matter? What is the priority? What is happening physiologically? What intervention fixes the actual problem?
Can this patient maintain an airway? Are they oxygenating effectively? Those two questions answer nearly every item in Respiratory I.