Final answer:
The most common preventable complication of abdominal surgery is peritonitis, which is inflammation of the peritoneum. It can occur when the wall of the alimentary canal is breached, and it requires emergency surgery and antibiotic therapy.
Step-by-step explanation:
The most common preventable complication of abdominal surgery is peritonitis, which is inflammation of the peritoneum. Peritonitis can occur when the wall of the alimentary canal is breached, allowing the contents to enter the peritoneal cavity. This can happen in cases such as perforated ulcers or bacterial infections associated with appendicitis. Peritonitis is a life-threatening condition that often requires emergency surgery and intensive antibiotic therapy.