Section 6C. Except as otherwise provided in chapter one hundred and fifty-two, if a cause of action exists against an employer under section one of chapter one hundred and fifty-three, or because of the negligence of the employer himself, for an injury resulting in death which is not instantaneous or is preceded by conscious suffering, if there is any person who would have been entitled to bring an action under section two B, the legal representatives of the deceased may, in the action under said section one, recover damages both for the injury and for the death, and, if the employer is also liable at common law, may in a separate count in the same action recover damages for conscious suffering resulting from the same injury.