Final answer:
The first step after a 39-year-old male sustains a leg laceration with signs of shock is to apply direct pressure to the wound. Type O negative blood is transfused in emergencies without known blood type. Mark's case illustrates how serious infections can require immediate and aggressive treatment.
Step-by-step explanation:
When a 39-year-old male sustained a large laceration to his leg and is experiencing signs of shock, the first step you should take is to apply direct pressure to the wound. This is to control bleeding, which is a priority in this situation. Only after bleeding is controlled and standard precautions are applied should the patient be placed on high-flow oxygen and a rapid head-to-toe assessment be conducted.
Following a motor vehicle accident, when a patient is rushed to the emergency department with severe bleeding, and their blood type cannot be immediately determined, the type of blood transfused is Type O negative because it is considered the universal donor and can be safely given to patients of any blood type. As for the individual with a knife cut, the layer of skin that had to be breached to cause bleeding is the dermis, which contains blood vessels. In Mark's case, he was quickly administered a broad-spectrum antibiotic to combat the infection, but even with this treatment, he experienced a rapid decline in his health, which is an example of how serious infections can turn critical and unresponsive to initial interventions.