Idiopathic Pulmonary Fibrosis (IPF)

Quantify the restriction preoperatively - PFTs for decreased FVC, total lung capacity, and FRC with a decreased diffusing capacity; HRCT for the UIP pattern. The GAP score (gender, age, FVC and DLCO) grades severity, and a high score means worse survival. Resting hypoxemia or breathlessness at minimal exertion tells you the disease is advanced.

Exam findings that matter - Fine bibasilar velcro crackles on inspiration and digital clubbing. A loud P2 points to pulmonary hypertension — confirm with an echocardiogram before a big case.

Small reserve, fast desaturation - Low FRC means a small oxygen store, so preoxygenate fully and expect apnea time to be short. Supplemental oxygen is indicated once SaO2 falls below 88%, and hypoxemia here is often poorly responsive to raising FiO2.

Protect the right heart - Pulmonary hypertension is common in advanced IPF. Avoid the things that raise PVR — hypoxia, hypercarbia, acidosis, hypothermia — and support systemic pressure so the RV stays perfused.

Assume reflux - Control of gastroesophageal reflux with a proton pump inhibitor is a standard supportive measure in IPF, so treat these patients as a reflux and aspiration risk on induction and emergence.

Know the antifibrotics - Most are on pirfenidone or nintedanib, a tyrosine kinase inhibitor. They slow progression and reduce exacerbations but don't change mortality much. GI upset is the leading reason patients stop them — diarrhea with nintedanib; rash, photosensitivity, and GI discomfort with pirfenidone.

Don't reach for steroids - Corticosteroids, azathioprine, and N-acetylcysteine are recommended against in IPF after the PANTHER-IPF trial. Don't assume a chronic steroid history, and don't treat the fibrosis with steroids intraoperatively.

Postpone through an exacerbation - Acute exacerbation shows ground-glass opacities and consolidation on imaging over the baseline UIP pattern and drives a steep decline in lung function and survival. Heart failure, infection, and thromboembolic disease must be excluded and treated first; elective surgery waits.

The lung biopsy case - Surgical lung biopsy remains the gold standard for diagnosis and many transplant centers require it, with bronchoscopic cryobiopsy an alternative. In a patient with advanced disease and respiratory failure, the risk of that biopsy is substantial — have the conversation before you take them back.

Transplant is the endpoint - Early referral is recommended, especially with a progressive decline in lung function, and transplant confers a survival benefit. Coexisting emphysema and pulmonary hypertension both worsen prognosis, so screen for both.

Idiopathic pulmonary fibrosis is progressive scarring of the lung interstitium from an unknown cause. Repetitive alveolar epithelial injury drives matrix deposition and scarring that destroys lung architecture; the pattern on HRCT and histology is usual interstitial pneumonia (UIP) — bilateral, subpleural, basal-predominant honeycombing with traction bronchiectasis.

The physiology is restrictive: reduced FVC, total lung capacity, and FRC with a low diffusing capacity. Destroyed alveolar-capillary membrane means gas exchange fails and hypoxic respiratory failure is the hallmark of advanced disease — and prognosis is worse in those who don't respond to oxygen. Many develop pulmonary hypertension and carry increased risk of pulmonary embolism and sudden cardiac death. Acute exacerbations cause rapid, often irreversible decline.