With the dyspneic cat, chest radiographs should be avoided until the patient is more stable. When in doubt, a diagnostic/therapeutic thoracocentesis should be performed first. If pleural effusion is detected on initial T-FAST ultrasound, the patient should be clipped, scrubbed and prepared for a life-saving thoracocentesis immediately. A thoracocentesis should be performed between the 7-9th intercostal spaces (ICS) to avoid the heart (3-5th ICS) or liver (caudal to the 9th ICS). A short cut approach to this rib space is to trace your finger up from the end of the sternum at the xyphoid, which is approximately at the 8th ICS. A thoracocentesis should be performed cranial to the rib, as the blood vessels and nerves lie caudal to the rib (e.g., “hiding” behind the rib). An appropriately sized needle (1.5” 22-gauge needle, depending on the size of the cat), a 3-way stopcock, and a 12-20 ml syringe should be used. In this cat, approximately 200 mls of pleural effusion was removed; further diagnostics including chest radiographs and thoracic ultrasound revealed a mediastinal mass. Check out our other VETgirl videos to learn more!