Prophylactic use of heparin for deep vein thrombosis in restrained psychiatric patients: a chart review.

OBJECTIVE: Physical restraint sometimes causes deep vein thrombosis (DVT) and pulmonary embolism. Although unfractionated heparin (UFH) is used for the prophylaxis of DVT, its effectiveness remained unknown for restrained patients.

METHOD: We conducted a chart review of restrained inpatients at Sakuragaoka Memorial Hospital in Japan. Restrained patients received subcutaneous injection of UFH 5000 IU bid from December 2008 to September 2010 [heparin (+) period] while UFH was not used from December 2010 to September 2012 [heparin (-) period]. A Doppler ultrasound scanning was performed to examine the presence of DVT. The incidence of DVT was compared between the two periods by chi-square test. A multiple logistic regression model was used to examine effects of demographic and clinical characteristics on the incidence of DVT.

RESULTS: No significant difference was found in the incidence of DVT between the heparin (+) and (-) periods [11.8% (11/93) vs. 11.1% (13/117)]. Sedation [odds ratio (OR) = 3.78], physical comorbidities (OR = 6.29) and a longer duration of restraint (OR = 1.22) were associated with the incidence of DVT.

CONCLUSION: The use of UFH was not associated with any reduction in the incidence of DVT in restrained psychiatric patients.