Final answer:
The most appropriate action for a patient with extreme difficulty breathing and bilateral wheezing is to Call for Advanced Life Support backup to provide immediate, life-saving interventions.
Step-by-step explanation:
In the scenario presented, the patient is showing severe respiratory distress with bilateral wheezing and lethargy, which may suggest an acute medical emergency such as an asthma attack or other forms of airway obstruction. The most appropriate immediate action would be b) Call for Advanced Life Support backup, as advanced support can provide immediate, life-saving interventions, such as drug therapy, advanced airway management, and possibly intubation if necessary. While administering oxygen via a nonrebreather or providing positive pressure ventilation are sensible steps, securing advanced life support is critical given the patient's severe condition.
Medical advances in respiratory distress syndrome (RDS), like the administration of pulmonary surfactant, have drastically reduced the mortality rates by about 50 percent. However, this question pertains to an acute emergency in a non-neonatal patient, signaling that advanced support and clinical interventions are urgently needed.