What should you do upon noticing an open knee fracture in an unconscious 52-year-old male?

When faced with an open knee fracture in an unconscious patient, the priority is to address any immediate life threats and manage the injury effectively. In this case, assessing distal pulses and applying sterile dressings is crucial.

Applying sterile dressings serves two main purposes: it helps to control bleeding and reduces the risk of infection by covering the open wound. Since the injury is an open fracture, there is potential for significant blood loss and contamination. By assessing distal pulses, you ensure that there is adequate blood flow beyond the injury site, which is essential for limb viability. If circulation is compromised, it may require further interventions to restore it.

The other options, while they have their merits, do not prioritize the immediate management required for an open fracture. Splinting the fracture without first controlling bleeding and protecting the wound can lead to further complications. Watching for changes in vital signs is important but does not address the existing condition directly. A head-to-toe assessment, although necessary for an overall evaluation of the unconscious patient, should be conducted after life-threatening conditions have been stabilized. Thus, focusing on the management of the fracture and ensuring effective circulation is the correct approach in this scenario.