You are transporting a male patient with a deep stab wound to the groin, with damage to the genitalia following an assault by his girlfriend. The patient is AAOx4, albeit restless. Vital signs on scene are P, 128 beats/min; R, 20 breaths/min; BP, 108/64 mmHg; and SpO2, 92%. Oxygen is being administered via nasal cannula. On reassessment, which sign would be most concerning to the EMT?