Informed consent, implied consent, and who is legally required to obtain it

Consent questions look like communication questions and are graded like law questions. The exam puts you alone in the room with a form and a patient who does not understand the procedure, or with a relative who says she can sign, and the answer turns on one fact: informed consent belongs to the provider, and everything the medical assistant does around it is witnessing, verifying and documenting.

Who must obtain it	The provider performing the procedure. The MA may witness the signature and confirm the form is complete — never supply the disclosure that makes it informed
What makes it informed	Nature of the procedure, risks, benefits, alternatives, and what happens if the patient declines — with a real chance to ask questions before signing
Implied consent	Inferred from the patient's conduct for routine, low-risk care: rolling up a sleeve for a blood pressure, holding out an arm for a routine venipuncture, tilting the head for an ear check
Express / written consent	Anything carrying material risk — excisions, surgery, anesthesia, sedation, and whatever the practice's policy lists
Emergency implied consent	A separate doctrine, and narrow: it applies only when the patient cannot consent and delay would cause harm. It does not cover routine care
Minors	Parent, legal guardian, or an adult holding documented authority such as a court order or a signed caregiver authorization. A grandparent, a stepparent, or "the adult who brought him" is not enough, and relayed telephone permission from a third party is not consent
Refusal	A competent adult may refuse anything, including a test his employer wants. Treating anyway is battery — intentional contact without consent. Document the refusal and notify the provider
Vaccine Information Statement	Federal law (42 U.S.C. 300aa-26) requires the current VIS before the dose is given, every single time, even for a patient who has had that vaccine and that VIS before
Living will vs proxy vs POLST/MOLST	A living will states the patient's wishes; a durable power of attorney for health care names the decision-maker; a POLST or MOLST is a signed medical order EMS can act on immediately and it travels with the patient
Notice of Privacy Practices acknowledgment	A receipt, not a consent. Refusing to sign does not block treatment — document the good-faith effort and the refusal (45 CFR 164.520(c)(2))

Where the point is lost: Two swaps decide most of these items. First, battery is the completed touch, assault is putting someone in apprehension of a touch, and negligence needs a breached standard of care plus harm — injecting a patient who has refused is battery every time, no matter how it was justified. Second, a signature is not consent if the conversation never happened: when the patient says "I still don't know what they're going to do," the answer is always to stop and get the provider, never to explain it yourself and never to have him sign now and ask later.