A boy undergoes eye surgery under day care anesthesia with succinyl choline and propofol and after 8 hours he stas walking and develops muscle pain. What is the cause?

This is most probably postoperative myalgia associated with succinyl choline. Myalgia: Postoperative skeletal muscle pain, which is paicularly prominent in the skeletal muscles of the neck, side and abdomen can occur. Most possible cause unsynchronized contraction of skeletal muscle (fasciculation).