Grade III (severe)

Acute cholecystitis associated with dysfunction of any of the following organs/systems:

1. Cardiovascular dysfunction: hypotension requiring treatment with dopamine ≥ 5 μg/kg per minute or epinephrine at any dose

2. Neurological dysfunction: alteration of consciousness

3. Respiratory dysfunction: PaO2/FiO2 ratio < 300

4. Renal dysfunction: oliguria, creatinine > 2.0 mg/dl

5. Hepatic dysfunction: PT-INR > 1.5

6. Hematologic dysfunction: platelet count < 100,000/mm3

Grade II (moderate)

Acute cholecystitis associated with any of the following conditions:

1. Leukocytosis > 18,000/mm3

2. Palpable mass in the right upper quadrant

3. Duration of symptoms > 72 h

4. Marked local inflammation (gangrene, peri-vesicular or hepatic abscess, emphysema, empyema, mucocele, etc.)

Grade I (mild)

Acute cholecystitis that does not meet criteria for grade III or II. It can also be defined as acute cholecystitis in a previously healthy patient, without organ dysfunction or moderate inflammatory changes in the gallbladder, and whose cholecystectomy is performed safely and with low operative risk