What is the standard of care required of a medical practitioner?

In a 1992 decision of this court, Philp J. adopted the words of Lord Heward, C.J. in Rex v. Bateman[26] as one of the clearest statements of the standard of care required of a medical practitioner[27]: If a person holds himself out as possessing special skill and knowledge and he is consulted, as possessing such skill and knowledge, by or on behalf of a patient, he owes a duty to a patient to use due caution in undertaking the treatment. If he accepts the responsibility and undertakes the treatment and the patient submits to his direction and treatment accordingly, he owes a duty to the patient to use diligence, care, knowledge, skill and caution in administering the treatment.... The law requires a fair and reasonable standard of care and competence.