Ventilator Wizards
Illness Illusions
Imaging Dragons
Sorcery of Somnolence
ICU alchemy
100
ARDS patient on volume control: TV 6 cc/kg, PEEP 12, plateau 28, driving pressure 16. Oxygenation remains poor.
Q.What ventilator variable is most strongly associated with mortality and should be reduced?
Driving pressure
100
CT: upper lobe predominant nodules + cysts in a smoker.
What is the electron microscopy finding?
Pulmonary Langerhans Cell Histiocytosis - positive for CD1a and/or CD207 (langerin) - Birbeck granules.
100
the combination of honeycombing, traction bronchiectasis, and basal-predominant reticulation with minimal ground-glass opacity defines this pattern.
usual interstitial pneumonia (UIP) pattern
100
AHI of this value or greater per hour is the threshold for diagnosing moderate obstructive sleep apnea.
15 events/hour
100
Digoxin toxicity classically causes this arrhythmia pattern: increased automaticity with impaired conduction, most commonly manifesting as this rhythm.
atrial tachycardia with AV block
200
You observe expiratory flow not returning to baseline before the next breath in a COPD patient.
Q. What is the best immediate ventilator adjustment?
Increase expiratory time (↓ RR or ↓ I:E ratio) to reduce auto-PEEP
200
Rapidly progressive cavitary nodules + sinus disease + AKI.
Granulomatosis with Polyangiitis
200
most common cause of empyema necessitans and may account for ~70% of cases
Mycobacterium tuberculosis
200
neck circumference greater than this value (in cm) is a risk factor for OSA in the STOP-BANG questionnaire.
40 cm (or 16 inches)
200
In tricyclic antidepressant overdose, a QRS duration greater than this value (in milliseconds) on ECG predicts an increased risk of seizures and arrhythmias.
100 ms
≥100 milliseconds (0.10 seconds) - increased risk of seizures,≥160 milliseconds (0.16 seconds)- increased risk of ventricular arrhythmias
300
A patient on pressure support develops worsening hypercapnia without change in RR. Waveforms show decreasing tidal volumes.
Q.What is the most likely mechanism?
Respiratory muscle fatigue leading to inadequate inspiratory effort
300
Crazy paving pattern in a patient with acute hypoxemia, but BAL shows milky fluid with PAS-positive material.
Diagnoses and treatment
Pulmonary Alveolar Proteinosis - whole lung lavage (WLL) or inhaled GM-CSF
300
in a neutropenic patient
invasive pulmonary aspergillosis
(Halo sign)
300
hypoglossal nerve stimulator (Inspire device) is FDA-approved for OSA patients who are CPAP-intolerant and have an AHI between 15 and 65, provided this diagnostic test excludes concentric collapse of the palate.
drug-induced sleep endoscopy (DISE)
300
In critically ill patients with muscle loss, serum levels of this protein are more accurate than eGFR
Cystatin C
400
Esophageal manometry shows large negative swings in pleural pressure during assisted ventilation in ARDS.
Q.What phenomenon is this, and why is it harmful?
Patient self-inflicted lung injury (P-SILI) due to excessive transpulmonary pressure
400
Female + Recurrent pneumothoraces + renal angiomyolipomas.
Diagnosing marker with serum levels
Lymphangioleiomyomatosis - serum vascular endothelial growth factor-D (VEGF-D) level > 800 pg/mL.
400
associated with microwave-popcorn industry xtra butter flavour
Bronchiolitis obliterans - diacetyl
400
SERVE-HF trial found that adaptive servo-ventilation (ASV) in patients with heart failure (EF ≤ 45%) and central sleep apnea had this alarming effect
increased cardiovascular mortality
400
In patients with hepatorenal syndrome who are hypoxemic, this vasopressor is associated with increased mortality
Terlipressin
500
During VV-ECMO for ARDS, ventilator settings are typically reduced to "rest settings." The recommended tidal volume and plateau pressure targets are these values.
Vt ≤4 mL/kg PBW and plateau pressure ≤25 cmH₂O
500
non-caseating granulomatous disorder, often misdiagnosed as sarcoidosis, arises from a type IV hypersensitivity response to this inhaled metal dust.
Diagnosing test for this disease?
Berylliosis - Beryllium Lymphocyte Proliferation Test (BeLPT) in BAL
500
Autosomal dominant disease due to mutation of this gene
Birt-Hogg-Dubé syndrome (BHD), FLCN gene mutations - Folliculin
(Skin showing fibrofolliculomas)
500
Congenital central hypoventilation syndrome (Ondine's curse) is caused by mutations in this gene.
PHOX2B
500
Acute renal failure, interstitial nephritis and nephrolithiasis is associated with this K+ sparing diuretic in the ICU
Triamterene