Psychiatric inpatients subjected to physical restraint have a higher risk of deep vein thrombosis and aspiration pneumonia.

Physical restraint in clinical settings can lead to potentially lethal complications. Although this is a life-and-death issue, no comprehensive large-scale study relating medical complications to physical restraint has yet been performed. The 1308 psychiatric inpatients in our retrospective cohort study were categorized into two groups: a physical restraint group (those who had been subjected to physical restraint while hospitalized; n = 110) and a non-physical restraint group (those never subjected to physical restraint; n = 1198). We assessed differences between the two groups with respect to the occurrence of medical complications subsequent to restraint. To control for potentially confounding factors, linear discriminant regression analysis was used to identify whether physical restraint itself affected the occurrence of medical complications. The physical restraint group had a higher risk for deep vein thrombosis (P < .01, OR = 6.0, 95%CI: 2.4-13.9) and aspiration pneumonia (P < .01, OR = 4.1, 95%CI: 2.1-7.6) when compared with the non-physical restraint group. Even after controlling for potentially confounding factors, physical restraint substantially raised the risk of deep vein thrombosis and aspiration pneumonia (P < .01, P = .01, respectively). Although this study population was derived from a single psychiatric unit, physical restraint may lead to serious medical conditions. To avoid this unwanted consequence, the use of physical restraint should be minimized and physical therapy is highly recommended.