What is the current state of the law in relation to the due care presumption in medical malpractice cases?

Maertins v. Kaiser Foundation Hospitals (1958) 162 Cal.App.2d 661, 328 P.2d 494, 75 A.L.R.2d 807, involved a malpractice action. A doctor, at the time of the trial, was practicing medicine in Maine 'and there was testimony that it [203 Cal.App.2d 516] was 'impossible' for him to come to California for the trial.' (p. 664, 328 P.2d p. 496.) The court instructed that the doctor was entitled to the due care presumption. Concerning the giving of this instruction the reviewing court said (pp. 665, 666, 328 P.2d p. 496): 'It is ordinarily error to give such an instruction where evidence is produced by the defendant as to the circumstances of his conduct which is alleged to be negligent. * * * The exception has so far only been applied where the person whose negligence is in question is either dead or unable to testify because of loss of memory. * * *