The difference between a bloated stomach and ascites lies in the presence of shifting dullness during physical examination, as well as symptoms such as abdominal distension and difficulty breathing. Here are the key points for distinction:

1. Presence of Shifting Dullness During Physical Examination

Ascites medically refers to an excessive accumulation of free fluid in the abdominal cavity. A bloated stomach, on the other hand, typically indicates obesity, relatively high blood lipids, and thickening of subcutaneous fat leading to abdominal protrusion. These conditions can generally be distinguished through physical examination. In patients with ascites, the doctor will detect a positive shifting dullness. In patients without ascites, the abdominal fat layer is thicker, and during the examination, the doctor can palpate the thickening of the abdominal fat layer with poor palpation of abdominal organs.

2. Presence of Abdominal Distension and Difficulty Breathing

Small amounts of ascites (less than 1000ml) may be asymptomatic. Moderate to large amounts of ascites often cause abdominal distension, and in severe cases, difficulty breathing may occur. In obese individuals with a bloated stomach, apart from the spherical expansion of the abdominal wall due to fat accumulation, there is also fat deposition in other parts of the body. However, they generally do not experience symptoms such as abdominal distension or difficulty breathing.

Ultrasonography (B-ultrasound) is a sensitive and convenient method for diagnosing ascites. It can distinguish between free and compartmentalized ascites and also detect and differentiate other liquid-containing structures such as ovarian cysts, abdominal cysts, abscesses, or hematomas.