Sleep Medicine and Chronic Lung Care

In depth

The one-page summary above is what the PDF prints. These sections go further.

GOLD 2026: assessment and the treatment cycle

GOLD separates airflow grade (GOLD 1–4 from post-bronchodilator FEV₁, covered on PFTs and Oxygen Delivery) from the ABE tool, which uses only symptoms and the past year of exacerbations. Symptoms are scored with the mMRC dyspnea scale or the CAAT (2026 renames the CAT the Chronic Airways Assessment Test); the cut points are mMRC 2 and CAAT 10. In 2026 a single moderate or severe exacerbation in the past year places a patient in group E. Earlier editions required two moderate exacerbations or one admission, so older item explanations may quote that rule.

Initial therapy for a patient naive to maintenance drugs: group A gets one bronchodilator; groups B and E get LABA + LAMA, preferably in one inhaler because single inhalers improve adherence; group E adds an ICS from the start when blood eosinophils are 300/µL or more. After that, care runs as a cycle: review dyspnea and exacerbations, assess technique, adherence, rehabilitation and other diseases, then adjust. If the patient is doing well, the current regimen continues.

GOLD weighs ICS by three tiers. Strongly in favor: a hospitalization for an exacerbation, two or more moderate exacerbations a year, eosinophils of 300 or more, or a history of asthma. In favor: one moderate exacerbation a year or eosinophils of 100 to under 300. Against: repeated pneumonia, eosinophils under 100, or past mycobacterial infection. Eosinophil counts fluctuate, so the cut points are approximate. ICS may be withdrawn after pneumonia or other important side effects; with eosinophils of 300 or more, withdrawal is more likely to be followed by exacerbations.

Patients already on LABA + ICS without exacerbations can stay on it if symptoms are low, or escalate to triple therapy if symptoms are high; those with no relevant exacerbation history may change to LABA + LAMA. With current exacerbations, eosinophils of 100 or more favor triple therapy, and under 100 favor LABA + LAMA.

Add-ons after triple or dual therapy: roflumilast for FEV₁ under 50% with chronic bronchitis; azithromycin, preferably in former smokers; and, for two moderate or one severe exacerbation with eosinophils of 300 or more, a biologic. Dupilumab trials (BOREAS, NOTUS) enrolled patients with chronic bronchitis and eosinophils of 300 or more and cut moderate or severe exacerbations by about a third; mepolizumab trials gave smaller reductions. Ensifentrine is listed as an option for persistent dyspnea.

Roflumilast (Daliresp) is an oral phosphodiesterase-4 inhibitor, 500 µg once daily; a 250 µg start for 4 weeks may reduce drop-out but is not the treatment dose. It is not a bronchodilator and does nothing for acute bronchospasm. Watch for diarrhea, nausea, weight loss, insomnia, and depression or suicidal thoughts; it is contraindicated in moderate to severe liver impairment, and strong enzyme inducers such as rifampin are not recommended with it.

GINA: why the reliever matters, biologics and devices

GINA no longer recommends SABA-only treatment, and the 2026 report keeps ICS-containing treatment for adults, adolescents and children. SABA-only treatment is linked to asthma deaths and urgent visits, regular SABA use down-regulates β₂ receptors and increases airway inflammation, and starting with SABA alone teaches patients that the reliever is the real treatment. As-needed low-dose ICS–formoterol cut severe exacerbations needing oral steroids by at least 60% compared with SABA alone in mild asthma.

Track 1 uses ICS–formoterol as the reliever at every step (as needed alone at steps 1–2, as maintenance and reliever from step 3). Track 2 uses a SABA reliever: at step 1 the patient takes ICS whenever SABA is taken; from step 2 a daily controller is required. Track 2 suits patients for whom ICS–formoterol is unavailable or not preferred and who will take daily controller therapy. A long-acting bronchodilator alone is contraindicated in asthma because it raises the risk of severe and fatal attacks while the inflammation goes untreated.

At step 5, before adding drugs, confirm the diagnosis, technique and adherence, and treat modifiable factors. Then phenotype: severe eosinophilic asthma can receive benralizumab, dupilumab, mepolizumab or reslizumab; severe allergic asthma, omalizumab or dupilumab. Dupilumab is labeled for eosinophilic or oral-steroid-dependent asthma from age 6 and also for chronic rhinosinusitis with nasal polyps, so polyps with high eosinophils favor it. Other step-5 add-ons are a LAMA (tiotropium from age 6) and low-dose azithromycin after specialist referral. No biologic treats acute bronchospasm.

Device choice (GOLD 2026, applies equally to asthma): a DPI works only if the patient can inhale forcefully and deeply through it; an MDI and, to a lesser extent, a soft mist inhaler need coordination and a slow, deep breath, so add a spacer or valved holding chamber or choose another device if in doubt. A patient who cannot use any of them gets a nebulizer. Consider cognition, dexterity, cost and the patient’s preference, keep device types to a minimum, and check technique and adherence at every visit before deciding a drug has failed.

Cystic fibrosis: modulators, inhaled drugs and infection control

Sweat chloride is the standard diagnostic test: 60 mmol/L or more indicates CF, 30 to 59 needs further testing, and under 30 makes CF unlikely without excluding it. Many adults born before 2010 were never newborn-screened, so lifelong productive cough, sinus disease and bronchiectasis in an adult still call for a sweat test.

Elexacaftor–tezacaftor–ivacaftor (Trikafta) is labeled for patients aged 2 and older with at least one responsive CFTR variant (F508del is the commonest). It acts on the defective protein, unlike dornase, hypertonic saline or inhaled antibiotics, which treat consequences. It carries a boxed warning for drug-induced liver injury and liver failure: check ALT, AST, alkaline phosphatase and bilirubin before starting, monthly for 6 months, every 3 months for the next 12 months, then at least yearly. Children need baseline and follow-up eye examinations for cataracts. Take it with fat-containing food about 12 hours apart, avoid grapefruit, avoid strong CYP3A inducers (rifampin, St John’s wort), and reduce the dose with strong or moderate CYP3A inhibitors. Modulators do not replace airway clearance and inhaled therapy.

The CF Foundation airway clearance guideline recommends regular clearance for every patient, individualizes the technique because none has been shown superior, and recommends aerobic exercise as an adjunct to clearance, not a substitute. Techniques are described on Airway Clearance and Suctioning.

Dornase alfa (Pulmozyme) is 2.5 mg once daily by an approved jet or mesh nebulizer, never diluted or mixed with other drugs. Ampules stay refrigerated at 2–8 °C in the foil pouch; an ampule that has spent more than 60 hours in total at room temperature, is cloudy or discolored, or is past its date is discarded. Inhaled mannitol (Bronchitol) is add-on maintenance for adults 18 and older: 400 mg (10 capsules) twice daily, only after a supervised tolerance test is passed, with a short-acting bronchodilator 5–15 minutes before every dose and the evening dose at least 2–3 hours before bedtime. Stop it for bronchospasm or hemoptysis, and replace the inhaler after 7 days.

People with CF pass resistant organisms such as Pseudomonas and Burkholderia to each other. Pediatric CF programs teach at least 2 m (6 ft) between people with CF, no shared cups, nebulizers or compressors, and daily cleaning of nebulizers and clearance devices.

Pulmonary rehabilitation, tobacco treatment and screening

The 2023 ATS guideline strongly recommends pulmonary rehabilitation for stable COPD, for COPD after an exacerbation admission, and for interstitial lung disease, and conditionally for pulmonary hypertension; patients should be offered center-based or telerehabilitation. Programs combine exercise training with education and self-management. Outcomes are exercise capacity, dyspnea and quality of life, not spirometry (the last point is classic teaching). A 2025 meta-analysis puts the minimal important difference in 6-minute walk distance at about 25 m in respiratory disease (48 m for the incremental shuttle walk).

Tobacco treatment follows the 5 A’s: ask every patient at every visit, advise in a clear and personal way, assess willingness to quit in the next 30 days, assist with a plan, counseling and medication, and arrange follow-up. First-line medications are varenicline, bupropion and nicotine replacement (patch, gum, inhaler, nasal spray). The 2020 ATS guideline prefers varenicline over the patch, over bupropion and over e-cigarettes, suggests adding the patch to varenicline, recommends starting varenicline even before the patient is ready to quit, and recommends treatment for longer than 12 weeks. GOLD finds no evidence that e-cigarettes are an effective or safe cessation aid. A hospital admission is a good time to start.

Vaccines for COPD in GOLD 2026: influenza every year; COVID-19 per current recommendations; one dose of PCV20 or PCV21; RSV for those aged 50 or over or with chronic heart or lung disease; Tdap if not given in adolescence; and zoster over age 50. National schedules change, so check the current local schedule. USPSTF 2021 recommends yearly low-dose CT for adults aged 50–80 with at least 20 pack-years who smoke or quit within 15 years, stopping after 15 years without smoking.

Self-management: GOLD pairs a written action plan with each treatable trait. For exacerbations it covers avoiding triggers, recognizing worsening (more breathlessness, more or more purulent sputum), what to do, and whom to call. In practice the plan tells the patient to start the prescribed rescue course early and contact the team, rather than wait or turn up the oxygen. Maintenance inhalers continue during an exacerbation.

EVALI and occupational lung disease

E-cigarette or vaping product use-associated lung injury peaked in September 2019; by February 2020 CDC counted 2,807 hospitalized cases or deaths, with 68 deaths. Vitamin E acetate was found in lavage fluid from 48 of 51 patients tested, and most patients used THC products, largely from informal sources. In the CDC series 95% had respiratory symptoms, 77% gastrointestinal and 85% constitutional symptoms, and GI symptoms could come first. It is a diagnosis of exclusion: ask about the device, substances, source and last use; image with a chest radiograph (CT if unclear); test for influenza and consider empiric pneumonia treatment. Admit if SpO₂ is under 95% on room air or the patient is in distress. Corticosteroids helped many patients and are used case by case. Follow up within 1–2 weeks of discharge and counsel to stop vaping.

Asbestos was used in insulation, ship materials and brakes. Pleural plaques, the commonest sign of exposure, appear 20–30 years later and are usually silent. Asbestosis is interstitial fibrosis in the peripheral lower lobes, with restriction and a low DLCO, 20–40 years after heavy exposure; care is supportive (oxygen, rehabilitation, vaccines, no further exposure). Smoking and asbestos multiply lung cancer risk, and mesothelioma has a median latency of about 40 years. Silicosis follows crystalline silica from sandblasting, stonecutting, engineered stone and quarrying: small upper-lobe nodules, sometimes eggshell calcification of hilar nodes (not specific), and a higher risk of tuberculosis, so exposed workers are tested yearly.

Home oxygen: the coverage details

Medicare NCD 240.2 group I covers a resting room-air PaO₂ of 55 mm Hg or less or SaO₂ of 88% or less. It also covers oxygen for sleep only when the PaO₂ is 55 or less or SaO₂ 88% or less during sleep in a patient whose awake values are 56/89% or higher, or when sleep lowers PaO₂ by more than 10 mm Hg or SaO₂ by more than 5% with symptoms of hypoxemia; and for exercise when values fall to those levels during exercise and oxygen corrects them. Group II needs a PaO₂ of 56–59 or SaO₂ of 89% plus dependent edema suggesting heart failure, pulmonary hypertension or cor pulmonale, or a hematocrit over 56%.

The treating practitioner orders and evaluates the test; a DME supplier cannot perform it. If an ABG and oximetry disagree, the ABG is used. For inpatients the qualifying test is done within 2 days of discharge. GOLD notes that long-term oxygen improves survival only in severe resting hypoxemia; in moderate resting or exercise-induced desaturation it does not lengthen survival or delay admission. Titrate to SaO₂ of 90% or more and recheck need and effect in 60–90 days. A normal resting saturation at sea level does not exclude severe hypoxemia during air travel. Oxygen targets in acute care and device choice are on PFTs and Oxygen Delivery.

Scoring rules, AHI and testing choices

The 2012 AASM update scores an adult apnea as a fall of at least 90% in the airflow signal for at least 10 seconds; no desaturation is needed. A hypopnea is a fall of at least 30% for at least 10 seconds with a 3% desaturation or an arousal. In 2013 the AASM kept 3% as its recommended rule but allowed 4%, because Medicare and other payers require a 4% desaturation; centers must record which rule they used. The choice changes the count: the 4% rule ignores hypopneas that end only in an arousal or a 3% dip, so the AHI is lower.

An apnea with continued or increasing effort (often paradoxical chest and abdominal motion) is obstructive, one without effort is central, and one that starts without effort and ends with effort is mixed. A respiratory effort-related arousal (RERA) is a run of increasing effort ending in an arousal that does not meet apnea or hypopnea criteria. AHI = apneas plus hypopneas per hour of sleep; RDI adds RERAs. Example: 34 apneas plus 46 hypopneas over 5 hours of sleep is 80 ÷ 5 = 16/h (moderate); dividing by 8 hours in bed would wrongly give 10/h.

The 2017 AASM diagnostic guideline: do not diagnose OSA from questionnaires or prediction tools alone (STOP-Bang estimates risk); use polysomnography or a technically adequate home sleep apnea test for uncomplicated adults likely to have moderate to severe OSA; and use polysomnography for significant cardiorespiratory disease, possible respiratory muscle weakness, awake or suspected sleep hypoventilation, chronic opioid use, past stroke or severe insomnia. One negative, inconclusive or technically inadequate home test is followed by polysomnography, not a repeat home test. Home devices do not measure sleep, so they divide by recording time and miss arousal-based hypopneas, which lowers the index. A split-night study (diagnosis then titration in one night) is reasonable when appropriate.

Overnight oximetry screens but does not count or classify events. Repetitive brief dips from a normal baseline suggest apnea and call for a sleep study; a sustained low saturation suggests hypoventilation or lung disease. Medicare accepts sleep oximetry for nocturnal oxygen qualification and requires polysomnography or a type II to IV home test for CPAP coverage.

PAP therapy and alternatives

The 2019 AASM PAP guideline strongly recommends PAP for OSA with excessive sleepiness and suggests it for impaired sleep-related quality of life and for hypertension. Treatment starts with home auto-CPAP or an in-lab titration in adults without major comorbidities; long-term treatment can be CPAP or auto-CPAP, and CPAP or auto-CPAP is suggested over bilevel for routine OSA. Education at the start, troubleshooting in the first weeks and telemonitoring are recommended.

Medicare covers CPAP for an AHI or RDI of 15 or more, or 5–14 with sleepiness, impaired cognition, mood disorder, insomnia, hypertension, ischemic heart disease or past stroke. Continued coverage after the 12-week trial needs use of 4 hours or more on 70% of nights in 30 consecutive days during the first 3 months, documented at a visit between day 31 and day 91. Bilevel without a backup rate is covered for OSA only after CPAP has been tried and proven ineffective; bilevel with a backup rate is not covered when the primary diagnosis is OSA.

Read a download in order: use, then leak, then residual events. Low use with a working pressure and normal leak is a comfort problem (mask, claustrophobia, ramp, coaching). A large leak with dry mouth points to the mouth: a chin strap or a full-face mask, then a new download, because a residual AHI measured through a big leak is unreliable. Good use, normal leak and a high residual obstructive AHI means the pressure is now too low, often after weight gain: retitrate with auto-CPAP or a lab study. NHLBI lists congestion, dry eyes or mouth, nosebleeds and runny nose as PAP side effects, managed with a humidifier or nasal spray, and advises stopping and calling the provider for stomach bloating.

For patients who cannot use PAP: a custom oral appliance made by a dentist advances the jaw and works best in mild to moderate OSA, with follow-up testing to confirm effect; positional therapy suits supine-dominant events; hypoglossal nerve stimulation is for selected moderate to severe OSA after PAP and oral appliances fail; weight loss, drug therapy for obesity and bariatric surgery help when obesity drives the disease. Oxygen alone does not prevent airway collapse. Before surgery, patients with OSA tell the anesthesia team, bring their device and use it during recovery whenever they sleep, especially on opioids.

Central sleep apnea and hypoventilation

Central apnea is a pause with no effort. In Cheyne–Stokes breathing, seen mostly in heart failure, slow circulation and sensitive chemoreceptors make the PaCO₂ swing around the apneic threshold, so breaths wax and wane and central apneas follow; the awake PaCO₂ is often low or low-normal. Treating the heart failure is the first step.

The 2025 AASM central apnea guideline (all conditional) suggests, for central apnea due to heart failure, CPAP, ASV, low-flow oxygen, acetazolamide and transvenous phrenic nerve stimulation, and suggests against bilevel without a backup rate. In SERVE-HF, ASV raised all-cause and cardiovascular mortality in heart failure with LVEF of 45% or less and predominant Cheyne–Stokes breathing, so ASV in reduced ejection fraction is limited to experienced centers with close monitoring. For treatment-emergent central apnea (central events that appear when CPAP removes obstruction) the guideline suggests CPAP, with bilevel with a backup rate, ASV or acetazolamide if events persist. Opioids and other drugs are a recognized cause of central apnea, which is one reason they call for a lab study.

The 2019 ATS obesity hypoventilation guideline: a serum bicarbonate under 27 mmol/L makes OHS unlikely when suspicion is low, and an ABG is drawn when suspicion is high; stable ambulatory patients receive PAP, CPAP rather than NIV when severe OSA coexists; patients hospitalized with hypercapnic failure go home on NIV until outpatient testing and titration, ideally within 2–3 months; and sustained weight loss of about 25–30% can resolve OHS. In COPD, GOLD suggests home NIV for persistent daytime PaCO₂ over 53 mm Hg after a recent admission. In COPD with hypercapnia, oxygen without ventilatory support can raise the PaCO₂ (classic teaching).

Exam pearls

• COPD group E needs only one moderate or severe exacerbation in GOLD 2026; ICS is added for eosinophils of 300 or more.
• Roflumilast needs FEV₁ under 50% with chronic bronchitis; it is not a rescue drug.
• Asthma: an ICS in every regimen; ICS–formoterol is the preferred reliever.
• Check technique, adherence and cost before stepping up any inhaled regimen.
• CF: modulators fix the protein; airway clearance still continues; exercise is an add-on.
• Rehabilitation improves exercise capacity and dyspnea; FEV₁ is not the measure of benefit.
• AHI divides by sleep time; a home test divides by recording time and runs low.
• Apnea 90% for 10 s needs no desaturation; hypopnea 30% for 10 s needs 3% (or 4%) or an arousal.
• Opioids, heart or lung disease, weakness or hypoventilation: lab polysomnography, not a home test.
• Mouth leak and dry mouth on nasal CPAP: chin strap or full-face mask before any pressure change.