Heat Therapy for Hematomas: Not Recommended in Acute Phase

Acute Phase Management (First 6-12 Hours)

The American Heart Association recommends localized cold therapy with or without pressure for hemostasis in closed bleeding and hematomas in extremities, as it is beneficial for reducing pain and potentially limiting hematoma size 1, 2
Cold compression significantly reduces femoral hematoma formation, decreasing hematoma size by approximately 20 cm² over 180 minutes, and reduces total body blood loss by 610 mL (95% CI, 415.6–804.4) and extravasation by 357 mL (95% CI, 184.6–529.3) in surgical settings 1
The primary mechanism of cold therapy is vasoconstriction, which limits ongoing bleeding and hematoma expansion 1

The European Society of Gastrointestinal Endoscopy notes that thermal hemostasis using heater probes or multipolar coagulation achieves primary hemostasis in up to 95% of patients with GI bleeding, although this is a different context from superficial hematoma management 3, 4, 5, 6, 7, 8
These devices apply 20-30 joules repeatedly until a blackened area forms, combining pressure (tamponade) and heat 3, 4, 5