A deontological normative theory holds that moral worth is an intrinsic feature of human actions, determined by formal rules of conduct. Thus, deontologists like Kant suppose that moral obligation rests solely upon duty, without requiring any reference to the practical consequences that dutiful actions may happen have.
I think you’d be hard-pressed to argue that considering the possible consequences of your actions shouldn’t be a part of your moral reasoning. In fact, it seems irresponsible not to take such consequences into consideration. But this seems to have been Kant’s view.