Locoregional anesthesia and coagulation.

The introduction of low molecolar weith heparin (LMWE) and the strong antithromboembolic prophylaxis protocols used in the USA, underlined the risk of spinal hemorrhage in patients receveing a neuraxial blockade. On the other side, the efficacy of these techniques over general anesthesia doesn't allow the anesthesist to miss this pratice, where possible. So it's necessary to quantify the spinal hematoma risk in patients assuming these drugs. Unfortunately, routine investigations on coagulation factors and platelets count are not reliable if patients are receiving LMWE. Waiting for dynamic tests concerning the coagulative status such as thromboelastography (TEG), many hospitals follow many different guidelines. For these reasons peripherical nerve block techniques are a good alternative, since they are not influenced by the efficacy of the coagulation system.