RESUMEN
Lumbar interbody fusion is one of the most commonly used surgical treatment of lumbar disease at present, but the hidden blood loss after surgery is large, accounting for 1/3 or even more than 1/2 of total blood loss. If not monitored and treated for the hidden blood, it can result in anemia and prolong bed time, thereby increasing the chance of infection. This paper summarizes the mechanism, influencing factors, calculation and treatment of hidden blood loss after lumbar fusion, so that the surgeon can have a correct understanding and evaluation of the hidden blood loss for the patients undergoing lumbar intervertebral fusion, and so as to reduce the occurrence of complications. This is very important for helping patients to pass perioperative period smoothly.