Mechanical restraint

Managing a patient with acute behavioural disturbance is a detailed flowchart for managing a patient with acute behavioural disturbance. Use the least restrictive intervention necessary to ensure the safety of the patient, staff and others.

Mechanical restraint (a type of physical restraint) is a restrictive practice, referring to the use of specifically designed physical devices (eg four-point restraints) to immobilise a patient to prevent them from injuring themselves or others. Mechanical restraint should only be applied in extreme circumstances, as a ‘last resort’, after all other evidence-based, person-centred and proactive strategies have failed, and only when the potential benefits outweigh the potential harms.

Restrictive practices are discouraged in all people, particularly children and older people, and people with developmental disability or cognitive impairment. If mechanical restraint is required for an adult, it must be proportionate to the risk of harm, and only be employed for the minimum duration that ensures the safety of the patient or others. Legal authorisation, documentation, monitoring, and nursing care must be undertaken in accordance with the relevant legislation and local policies. If mechanical restraint is required, document the rationale for its use, the type of restraint used, the patient’s response, monitoring undertaken, the duration of restraint, and any adverse events. For more information, see:

• Principles of care for a patient with acute behavioural disturbance
• Restrictive practices, the law, and the responsibility of the doctor.

Mechanical restraint has been associated with severe adverse events, including:

• asphyxia and death—if restrained in the prone position, or if the patient has unrecognised oversedation
• severe agitation, local pressure injuries, nerve injuries and, rarely, death if the patient is insufficiently sedated.

If mechanical restraint is required, do not use prone restraint. Observe the patient continuously to ensure their airway, breathing and circulation are not obstructed, and the restraint devices are not causing injury.

If a patient in police custody presents with mechanical restraint in place, employ verbal de-escalation and psychological intervention techniques and release the restraint as soon as it is safe to do so, or when the desired level of sedation is achieved—see the specific approach to Pharmacological management for acute behavioural disturbance in adults. Ensure documentation is completed each time a patient is physically restrained using mechanical restraint devices.