What is the difference between professional malpractice and ordinary negligence?

While recognizing that "the dividing line between 'ordinary negligence' and 'professional malpractice' may at times be difficult to place" (38 Cal.App.3d at p. 1007, 113 Cal.Rptr. 811), the Gopaul court found no difficulty with the facts before it and affirmed the judgment of nonsuit. "The need to strap plaintiff to the gurney while she was ill and unattended would have been obvious to all. The situation required no professional 'skill, prudence and diligence.' It simply called for the exercise of ordinary care." (Gopaul v. Herrick Memorial Hosp., supra, 38 Cal.App.3d at p. 1007, 113 Cal.Rptr. 811.) "The test reasonably must be whether the negligence occurred within the scope of the 'skill, prudence, and diligence commonly exercised by practitioners of his profession.' [Citation.]" (Ibid.)