In this VETgirl online veterinary continuing education blog, we demonstrate how to perform a "Hawaiian Punch" 2-needle, open abdominocentesis. Abdominocentesis is an important procedure that every veterinarian must be able to perform, as it helps us diagnose acute abdomen (e.g., uroabdomen, septic peritonitis, etc.), neoplasia (e.g., hemoabdomen), and metabolic disease (e.g., ascites secondary to heart disease versus hypoproteinemia, etc.). Using sterile technique, we use two 22-gauge sterile needles to tap the abdomen. Fluid should be collected into sterile containers (e.g., purple top, red top) and evaluated immediately. Learn more in this VETgirl video! NOTE: This was performed post-mortem in a patient.