Medical Assistance in Dying (MAID) is a legal option in Canada that allows an eligible person to receive medical intervention to intentionally end their life. This procedure is performed by a physician or nurse practitioner who directly administers a substance. Successfully achieving a peaceful and predictable death requires a specific, controlled pharmacological protocol. The medications used are chosen for their rapid, reliable action and are administered in a precise sequence to ensure patient comfort and certainty of outcome.
The Standard MAID Drug Protocol
The process of clinician-administered MAID follows a standardized pharmacological approach. While specific drug agents may vary slightly across different regions or based on drug availability, the overall protocol generally involves two or three distinct, sequential stages.
The first stage often includes an optional pre-medication to alleviate anxiety and discomfort before the main procedure begins. The second, and most substantial, stage involves the rapid induction of a deep, irreversible comatose state. The final stage introduces agents that actively stop the body’s essential functions, leading to death. The entire process is typically completed quickly, with death often occurring within ten minutes of the first injection of the main protocol drugs.
Drugs for Sedation and Coma Induction
The swift induction of deep unconsciousness is achieved using powerful central nervous system (CNS) depressants, most commonly an anesthetic agent called propofol, or a high-dose barbiturate. Before the coma-inducing agent, an anxiolytic like midazolam, a benzodiazepine, is often administered intravenously to reduce anxiety and promote relaxation. This step prevents any awareness during the final stages.
Propofol is a rapid-acting anesthetic that is frequently used in operating rooms to induce general anesthesia. In the context of MAID, it is administered at a dose far exceeding that used for surgery, typically around 1000 milligrams, to ensure a swift and profound coma. Propofol works by enhancing the inhibitory effects of the neurotransmitter gamma-aminobutyric acid (GABA). This widespread inhibition of CNS activity results in a loss of consciousness within seconds to a minute of administration.
Alternatively, some protocols utilize high-dose barbiturates, such as pentobarbital or thiopental, for coma induction. These drugs, like propofol, also act on the GABA-A receptor in the brain, but pentobarbital can also directly activate the receptor at high concentrations. The dosage of pentobarbital used for MAID is lethal on its own, often over 50 times the dose used for a typical hospital sedative, ensuring the resulting coma is deep and irreversible.
The high concentration of these agents can sometimes cause irritation and pain at the injection site, so protocols frequently include a local anesthetic, such as lidocaine, mixed with the propofol. Providers are trained to confirm the absence of response before proceeding to the final medications. The respiratory depression caused by the sheer dose of the anesthetic agent can sometimes lead to breathing stopping even before the final drug is administered.
Medications Ensuring Cardiopulmonary Arrest
The final medications are administered to ensure the cessation of breathing and heartbeat. The most common agents used in Canadian protocols for this purpose are neuromuscular blocking agents. These drugs, such as rocuronium or cisatracurium, are muscle relaxants that block the signals between nerves and muscles.
Rocuronium, administered in a high dose, competitively blocks the nicotinic acetylcholine receptors at the neuromuscular junction. This action results in the paralysis of all voluntary muscles, including the diaphragm and intercostal muscles necessary for breathing. The resulting respiratory arrest is rapid, typically occurring within minutes.
Some protocols may also include a cardiotoxic agent to directly and immediately stop the heart, though this is less common than the use of neuromuscular blockers. High-dose potassium chloride (KCl) is one such agent used in some variations of the protocol. When administered intravenously, the sudden surge of potassium ions disrupts the heart’s electrical conduction system.
This disruption causes an immediate and sustained depolarization of the cardiac cells, leading to asystole. Another cardiotoxic agent, bupivacaine, a local anesthetic, is also used in some protocols to induce cardiac arrest.