Lift the lip to check mucous membrane colour. Wet, bubblegum pink is healthy. Gums that look pale pink, dull, porcelain white, or ash-grey indicate extreme, life-threatening anaemia or severe cardiovascular shock. Tissues are not receiving the oxygen required to maintain organ viability.

When red blood cells are destroyed rapidly, the massive release of free haemoglobin is processed by the liver into bilirubin. This pigment floods the tissue spaces, staining the skin, ear flaps, gums, and whites of the eyes (sclera) a prominent yellow. Severe pre-hepatic icterus indicates an acute, high-risk haemolytic crisis.

When autoantibodies trigger intravascular lysis (RBC destruction directly inside the blood vessels), free haemoglobin is filtered by the kidneys. This causes severe haemoglobinuria, changing the urine colour from straw-yellow to dark tea, cola-brown, or dark red. Intravascular haemolysis represents a critical emergency.

Count the breathing rate when the animal is resting or deeply asleep. A healthy resting rate is under 30 breaths per minute. A rate consistently exceeding 35, or open-mouthed gasping, abdominal "pumping", or panicking when lying down, is a major warning of severe oxygen starvation or a pulmonary thromboembolism.

Inspect the inner ears, belly skin, and oral gums for small, pinpoint red or purple spots. These dots (petechiae) indicate spontaneous microvascular bleeding caused by severe, acute platelet loss. This signals either concurrent thrombocytopenia (Evans Syndrome) or Disseminated Intravascular Coagulation (DIC).