The role of suction drainage in the management of peri-operative bleeding in Total and Unicomcompartmental knee arthroplasty : a retrospective comparative study

Background: Suction drainage is commonly applied after total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) to reduce hematoma, swelling and to favor surgical wound healing. However, its efficacy remains controversial; thus, the purpose of this study is to evaluate drainage efficiency in the management of postoperative bleeding in TKA and UKA. Methods: The cohort comprised 134 clinical records of patients affected by knee osteoarthritis (OA) who underwent either TKA or UKA. All the patients were subdivided into 2 groups: the first one with drainage and the second one without drainage (respectively 61 and 73 patients). For each group, hemoglobin levels in the preoperative, first, second and third postoperative day were collected. Postoperative complications such as swelling, bleeding from the surgical wound or the need for blood transfusion, were also recorded. Results: Our results did not show any significant difference of hemoglobin levels in the first (p = 0.715), second (p = 0.203) and third post-operative day (p = 0.467) between the two groups. Moreover, no significant correlation between knee swelling or transfusion rate and the drainage was observed (p = 0.703 and p = 0.662 respectively). Besides, a significant correlation was found between bleeding from the surgical wound and the absence of drainage (p = 0.006). Conclusions: The study demonstrates how the routine use of suction drainage does not provide substantial benefits in the postoperative blood loss management after TKA or UKA.