Hemoptysis

Hemoptysis is the expectoration of blood arising from the lower respiratory tract. It is a finding, not a diagnosis. Infection, airway inflammation, bronchiectasis, malignancy, pulmonary embolism, cardiac disease, trauma, procedures, and antithrombotic therapy can all be part of the clinical picture. Hemoptysis is commonly described as non-massive when the volume is 100 mL or less over 24 hours and massive when it is at least 100 mL in 24 hours, at least 100 mL in one hour, or any amount that causes airway obstruction, respiratory failure, impaired gas exchange, or hemodynamic instability. These measurements are estimates, not precise boundaries. A patient can deteriorate from a smaller amount if blood or clot blocks the airway. The immediate danger is often asphyxia rather than blood loss alone. Blood can obstruct the tracheobronchial tree, while blood entering the alveoli displaces air and reduces oxygen transfer. That is why the first question is not “What disease caused this?” It is “Can this patient keep the airway open and oxygenate?”