In Macbeth, is Macduff irresponsible in leaving behind his family when he flees to Malcolm?
Lady Macduff certainly thinks so. In Act 4 Scene 2, Lady Macduff asks Rosse why her husband has fled the region. Rosse does not want to give away any information, so he tells her that she must trust Macduff's judgement. But Lady Macduff thinks that he is a coward for leaving his family behind unattended and without any apparent reason. After Rosse leaves, the murderers enter and slaughter Macduff's entire family and court.
Of course, Macduff had no way of predicting that murderers would enter his castle to kill his family; however, he is aware that Macbeth is on a killing spree and he does suspect that Macbeth is suspicious of him. These should have been clues to Macduff that Macbeth may have been plotting to do him harm.