What criteria are considered for massive pulmonary embolism?

In the context of massive pulmonary embolism, the criteria that define this condition primarily focus on hemodynamic instability. The presence of sustained hypotension, persistent bradycardia, or pulselessness indicates a significant compromise in cardiac output and perfusion due to obstruction in the pulmonary circulation. This obstruction results from the embolism, which effectively reduces blood flow to the lungs and can critically affect right ventricular function.

Sustained hypotension is defined as a drop in systolic blood pressure to less than 90 mmHg or a decrease of at least 40 mmHg in a previously normotensive individual. This level of hypotension signifies a state of shock that necessitates immediate intervention. Persistent bradycardia or pulselessness further suggests the heart is unable to maintain adequate circulation, indicating a dire situation often associated with massive pulmonary embolism.

Other options do not align with the critical features that define a massive pulmonary embolism. Moderate hypoxemia and tachycardia may occur in various scenarios and could indicate other forms of respiratory or cardiac compromise. Elevation of pulmonary capillary wedge pressure is more characteristic of left heart failure or fluid overload rather than a specific indicator of massive pulmonary embolism. Normal blood pressure with respiratory distress indicates