Background: Hyperosmolar therapy, using either hypertonic saline (HTS) or mannitol (MT), is considered the treatment of choice for intracranial hypertension, a disorder characterized by high intracranial pressure (ICP). However, hyperosmolar agents have been postulated to impair coagulation and platelet function. The aim of this study was to identify whether HTS and MT could affect coagulation in moderate traumatic brain injury (TBI) patients. Methods: In this prospective and randomized double-blind study, we included adult patients withmoderate TBI. Patients were divided into two groups according to the type of hypertonic solution administered. Group A patients received 20% MT and group B patients received 3% HTS. Rotational thromboelastometry (ROTEM) parameters were used to assess coagulation and platelet function. Results: ROTEM parameters included CT (clotting time), CFT (clot formation time), maximum clot firmness (MCF) measured byMCF (EXTEM and INTEM), MCF (FIBTEM) and standard coagulation tests (p > 0.05). No significant differenceswere found between the two groups. Moreover, ROTEM parameters did not show significant changes at different timepoints after administration of the hyperosmolar solutions (p > 0.05). Conclusions Overall, use of 3% HTS and 20% MT for the control of ICP did not significantly affect patients' coagulation function. Therefore, hyperosmotic solution is safe and does not increase the risk of intracranial rebleeding. (C) 2017 Elsevier Inc. All rights reserved.