In Cobbs v. Grant (1972) 8 Cal. 3d 229, the California Supreme Court held that where "a doctor obtains consent of the patient to perform one type of treatment and subsequently performs a substantially different treatment for which consent was not obtained, there is a clear case of battery. . When an undisclosed potential complication results, the occurrence of which was not an integral part of the treatment procedure but merely a known risk, the courts are divided on the issue of whether this should be deemed to be a battery or negligence. . . . California authorities have favored a negligence theory. . . .Dean Prosser surveyed the decisions in this area and concluded, 'The earliest cases treated this as a matter of vitiating the consent, so that there was liability for battery. Beginning with a decision in Kansas in 1960 . . ., it began to be recognized that this was really a matter of the standard of professional conduct . . . . The prevailing view now is that the action . . . is in reality one for negligence in failing to conform to the proper standard . . . .' . . . "Although this is a close question, either prong of which is supportable by authority, the trend appears to be towards categorizing failure to obtain informed consent as negligence. That this result now appears with growing frequency is of more than academic interest; it reflects an appreciation of the several significant consequences of favoring negligence over a battery theory. . . . Most jurisdictions have permitted a doctor in an informed consent action to interpose a defense that the disclosure he omitted to make was not required within his medical community. However, expert opinion as to community standard is not required in a battery count, in which the patient must merely prove failure to give informed consent and a mere touching absent consent. Moreover a doctor could be held liable for punitive damages under a battery count, and if held liable for the intentional tort of battery he might not be covered by his malpractice insurance. . . . "We agree with the majority trend. The battery theory should be reserved for those circumstances when a doctor performs an operation to which the patient has not consented. When the patient gives permission to perform one type of treatment and the doctor performs another, the requisite element of deliberate intent to deviate from the consent given is present. However, when the patient consents to certain treatment and the doctor performs that treatment but an undisclosed inherent complication with a low probability occurs, no intentional deviation from the consent given appears; rather, the doctor in obtaining consent may have failed to meet his due care duty to disclose pertinent information. In that situation the action should be pleaded in negligence." (Cobbs v. Grant, supra, 8 Cal. 3d at pp. 239-241; see also Prosser & Keeton, The Law of Torts (5th ed. 1984) 18, p. 119 "With the patient unconscious under an anaesthetic, and unable to be consulted, the mere desirability of the operation does not protect the surgeon, who becomes liable for battery--which . . . renders quite immaterial any question of whether he has complied with good professional practice".) In Cobbs v. Grant (1972) the California Supreme Court explained that the doctrine is based on four "postulates." These postulates incorporate the concept that patients generally do not have medical knowledge and rely upon their doctors for information. The doctrine also acknowledges that "a person of adult years and in sound mind has the right, in the exercise of control over his own body, to determine whether or not to submit to lawful medical treatment." (Ibid.) To be effective, a patient's consent to treatment must be an informed consent. (Ibid.) The California Supreme Court held that a physician has a duty to disclose to a patient 'the available choices with respect to proposed therapy and . . . the dangers inherently and potentially involved in each.' (Id., at p. 243.) Under Cobbs, the scope of a physician's duty to disclose is measured by the amount of knowledge a patient needs in order to make an informed choice. (Id., at p. 245.) At minimum, a physician must disclose 'the potential of death or serious harm' known to be inherent in a given procedure and an explanation in lay terms of the complications that might occur. (Id., at p. 244) See also Arato v. Avedon (1993) 5 Cal. 4th 1172, 1190 23 Cal. Rptr. 2d 131, 858 P.2d 598.) In addition to these 'minimal' disclosures, the physician must also reveal to the patient 'such additional information as a skilled practitioner of good standing would provide under similar circumstances.' (Cobbs v. Grant, supra, 8 Cal. 3d at pp. 244-245).