Massive hemoptysis

Hemoptysis is expectoration of blood from below the vocal cords, worked up with chest radiograph, then CT, then bronchoscopy, and managed by treating the underlying cause plus tranexamic acid, bronchoscopic hemostasis, or bronchial artery embolization for ongoing bleeding.

Bronchiectasis is chronic, irreversible bronchial dilation from a cycle of infection, inflammation, and airway destruction, diagnosed by high-resolution CT and managed with airway clearance, treatment of the underlying cause, and antibiotics for exacerbations.

Tuberculosis, caused by Mycobacterium tuberculosis, remains a leading global cause of infectious death and presents as latent infection, primary/secondary pulmonary disease, or extrapulmonary and disseminated (miliary) disease. Diagnosis rests on AFB smear, NAAT, and mycobacterial culture (the gold standard), and drug-susceptible active disease is treated with a four-drug regimen (isoniazid, rifampin, pyrazinamide, ethambutol) for 2 months followed by isoniazid plus rifampin for 4 to 7 months.

Lung cancer is the leading cause of cancer death worldwide, split into non-small cell lung cancer (NSCLC, 80% of cases: adenocarcinoma, squamous cell, large cell) and small cell lung cancer (SCLC, 10-15%), both driven overwhelmingly by cigarette smoking. Diagnosis requires tissue histopathology, staging drives treatment (TNM staging for NSCLC, limited versus extensive stage for SCLC), and management ranges from lobectomy in early-stage disease through concurrent chemoradiation and consolidation immunotherapy in locally advanced disease to targeted tyrosine kinase inhibitors, immune checkpoint inhibitors, or platinum-based chemotherapy in metastatic disease.

Pulmonary embolism is thrombus, usually from a lower-extremity deep vein thrombosis, obstructing the pulmonary arterial circulation and causing V/Q mismatch, right ventricular strain, and hypoxemia. Diagnosis follows Wells criteria (with PERC in low-risk patients) to sequence D-dimer, CT pulmonary angiography, and V/Q scanning, and management is risk-stratified anticoagulation escalating to thrombolysis or embolectomy for hemodynamic instability.

Mitral stenosis is obstruction of left atrial emptying from a narrowed mitral valve, overwhelmingly rheumatic in origin. It causes left atrial hypertension, atrial fibrillation, and pulmonary congestion, with a diastolic rumble and opening snap; severe symptomatic disease is treated with percutaneous balloon valvuloplasty or valve surgery.

Disseminated intravascular coagulation is a secondary, systemic activation of coagulation and fibrinolysis, most often from sepsis, that simultaneously consumes platelets and clotting factors, causing microvascular thrombosis and bleeding. Diagnosis rests on a laboratory constellation, thrombocytopenia, prolonged PT and aPTT, low fibrinogen, and elevated D-dimer, in a predisposing clinical setting, and management centers on treating the underlying trigger while replacing blood components only for active or high-risk bleeding.

ARDS is acute (within 1 week), bilateral, non-cardiogenic hypoxemic respiratory failure from diffuse alveolar damage, diagnosed by the 2012 Berlin criteria and graded by the Pao2/Fio2 ratio. Management is lung-protective ventilation, PEEP titration, early prone positioning for severe disease, conservative fluid strategy, and treatment of the inciting insult.

Von Willebrand disease is the most common inherited bleeding disorder, caused by deficient or dysfunctional von Willebrand factor, producing mucocutaneous bleeding from impaired platelet adhesion plus a mild secondary factor VIII deficiency. Diagnosis rests on the vWF antigen, ristocetin cofactor activity, and factor VIII activity panel, and management centers on desmopressin for type 1, vWF concentrate for severe or desmopressin-unresponsive disease, and antifibrinolytics for mucosal bleeding.

Hereditary hemorrhagic telangiectasia is an autosomal dominant vascular dysplasia, most often from ENG or ACVRL1 mutations, causing mucocutaneous telangiectasias and visceral arteriovenous malformations diagnosed by the Curacao criteria. Management combines iron repletion and epistaxis control with lifelong screening and embolization of pulmonary arteriovenous malformations to prevent paradoxical stroke and brain abscess.