Final answer:
The next step for a 46-year-old female with signs and symptoms of SBO and free air in the peritoneal cavity is immediate surgery.
Step-by-step explanation:
The next step for a 46-year-old female in the emergency department (ED) with signs and symptoms of small bowel obstruction (SBO), crampy abdominal pain, and free air in the peritoneal cavity on radiograph is immediate surgery. Free air in the peritoneal cavity is a sign of a perforated bowel, which is an emergency that requires surgical intervention. Surgery will be necessary to repair the perforation and resolve the obstruction.