Fatal thromboembolic disease: a risk in physically restrained psychiatric patients

Physical restraint is used in circumstances where patients exhibit behavior deemed threatening to their health and/or those around them. This practice has been associated with morbidity and mortality in the context of police custody, hospitals and long-term care facilities. While most of these events relate to short-term immobilization, the risks associated with prolonged physical restraint of psychiatric patients are largely unknown.

A retrospective review was performed at the Provincial Forensic Pathology Unit for cases of death occurring in physically restrained psychiatric patients.

We identified three patients who were immobilized by 4 point, 3-to-5 point and waist physical restraints. The immobilization periods ranged from 3 to 5 days. On autopsy, occlusive pulmonary thromboemboli were identified in each patient. None of the patients had previously recognized coagulopathies or significant risk factors for deep vein thrombosis. Postmortem genetic studies for Factor V and prothrombin mutations were negative.

Deep vein thrombosis is likely an under recognized occurrence in physically restrained patients under psychiatric care. We propose that deep vein thrombosis and pulmonary embolism be recognized as a risk factor for prolonged physical restraint. As a result, prospective studies examining the incidence and prevention of this adverse outcome is indicated.