A 38-year-old woman with a history of migraine undergoes an elective laparoscopic cholecystectomy under general anaesthesia. The anaesthetist, after obtaining verbal consent from the patient the evening before surgery, does not document the consent in the medical record. The patient wakes up with postoperative nausea and vomiting (PONV) and later files a complaint stating she was not informed about the risk of PONV and that her consent was not valid. The hospital's legal team argues that consent was obtained, though not documented. Which statement BEST reflects the legal and ethical position regarding consent in this case?