Final answer:
Decreased bowel sound in all quadrants of the abdomen is the correct answer as it could indicate a serious post-surgical complication such as ileus or bowel obstruction.
Step-by-step explanation:
The nurse should identify decreased bowel sound in all quadrants of the abdomen as an indication of a complication of the lumbar laminectomy surgery. While an oral temperature slightly above normal and clear drainage on the dressings can be typical post-operative findings, decreased bowel sounds might suggest a complication such as an ileus or bowel obstruction, which can be serious and require further assessment. Although drain output should also be monitored, 75 mL in 4 hours does not typically indicate a complication.