[Variables influencing bleeding during total hip arthroplasty].

PURPOSE OF THE STUDY: The purpose of this retrospective analysis was to study the parameters having an effect on blood loss during or after total hip arthroplasty. We examined a series of 350 procedures for primary degenerative hip disease with a normal course (n = 100), rapidly destructive degenerative disease (n = 100), and secondary joint degeneration due to atraumatic osteonecrosis of the femoral head (n = 100) or rheumatoid disease (n = 50).

MATERIAL AND

METHODS

All arthroplasties were performed via the transtrochanteric approach using Charnley-Kerboull implants. The volume of blood loss was calculated by noting compensated blood loss (transfusion during the procedure and shortly thereafter), and estimated non-compensated loss using the Nadler and Mercuriali and Inghilleri formula. We examined the influence of age, gender, obesity, and surgeon experience. Data were analyzed with the Student-Fisher reduced deviation method was used for quantitative and qualitative variables and the coefficient of correlation for quantitative variables.

RESULTS

Blood loss, calculated in ml packed red blood cells (hematocrit 100%), was 573 ml for arthroplasties with a normal course, 713 for arthroplasties secondary to osteonecrosis of the femoral head, and 950 ml for rapidly destructive degenerative disease and finally 609 ml for patients with rheumatoid arthritis. Considering 35% as normal for hematocrit, total estimated blood loss was 1,640, 2,040, 2,710, and 1,740 ml respectively in the different groups. Compared with the group of patients who had a normal course, total blood loss was significantly higher when arthroplasty was performed for osteonecrosis and rapidly destructive degenerative disease (p < 0.001). Age, obesity, and duration of the intervention had no effect on blood loss. Female gender and operator experience had a favorable influence in the group of patients who underwent hip surgery for primary degenerative disease. Blood loss occurring during or shortly after total hip arthroplasty was greater in men, when the procedure was performed for osteonecrosis, and most importantly for rapidly destructive diseases.

DISCUSSION: In clinical practice, the influence of gender is not significant enough to require specific preoperative transfusion plans. Conversely, certain etiologies of the joint disease impose transfusion in all such patients, using a blood volume which usually exceeds the possibilities of auto-transfusions.