*3.3.3 Particle-associated aspiration*

If particulate matter is present in the aspirate it can lead to variable degrees of airway obstruction. The severity of airway obstruction depends upon the size of the particle and the caliber of the airways. Aspiration of a larger particle can even lead to complete airway obstruction with subsequent sudden respiratory distress, cyanosis, and aphonia that may lead to sudden death if the obstruction is not immediately relieved. Smaller particles in the distal airways cause less severe obstruction and gradual course of respiratory symptoms as irritative cough, wheezing, dyspnea and superimposed bacterial pneumonia if the distal obstruction persists for more than 1 week. Chest X-Ray could show atelectasis or obstructive emphysema with a mediastinal shift and elevated diaphragm as shown in **Figure 2** below.

#### **Figure 2.**

*A chest radiograph (on the left) for a patient with a witnessed aspiration of food particles after neurointervention procedure under sedation, showing right upper lobe atelectasis and bilateral pulmonary edema and infiltrates. (On the right), the resolution of collapse and infiltrates after 2 days of respiratory support with invasive ventilation and Tazocin antibiotics in ICU. Picture courtesy of Dr. El Sayed E lKarta with his permission, Hamad Medical Corporation, Doha, Qatar.*
