Scalp laceration: an obvious 'occult' cause of shock.

Scalp lacerations are often present in patients requiring emergency care for blunt trauma. These injuries are most commonly seen in unrestrained drivers or occupants involved in motor vehicle crashes in which the victim is partially or totally ejected. Patients with scalp lacerations often have associated injuries that redirect the clinician's attention to other injury sites. Some scalp lacerations are severe enough to cause hypovolemic shock and acute anemia. If the patient arrives in shock, the perfusion pressure may be low, and there may be minimal active scalp bleeding. Under such circumstances, the scalp wound may be initially dismissed as trivial and attention appropriately turned to assuring an adequate airway, establishing intravenous lines, initiating volume resuscitation, and searching for more "occult" sources of blood loss. However, as the blood pressure returns toward normal, bleeding from the scalp wound becomes more profuse and presents a hemostatic challenge to the clinician. A case presentation illustrates some of these issues and confirms the effectiveness of an often overlooked but simple technique to control scalp hemorrhage--Raney clip application.