[Use of post-operative drainage and auto-transfusion sets in total knee arthroplasty].
OBJECTIVE
The aim of the study was to show advantages of post-operative collection of shed blood and its return to the patient's circulation, using blood-reinfusion sets, in terms of requirements for homologous blood, transmission of infections and posttransfusion reactions in total knee arthroplasty.


METHODS
Two groups of patients were studied. In group 1, comprising 88 patients, shed blood was collected by means of sets for post-operative wound drainage and subsequent autotransfusion. In group 2, with 44 patients, the standard Redon drainage system was used and blood losses were compensated for by homologous blood. Osteoarthrosis of the knee joint was the indication for total knee arthroplasty. Patients with a hemoglobin level lower than 110 g/l, rheumatoid arthropathy, hemophilic arthropathy, coagulopathy, infectious or cancer diseases, or liver or kidney failure were not included, as well as patients who were treated with non-steroid anti-rheumatic drugs, steroids or anticoagulation drugs.


METHODS
Post-operative blood losses within 6 h of surgery, by 24:00 hours on the day of operation and on the 1st and 2nd postoperative days were recorded. The amount of returned blood and requirements for homologous blood transfusion were also recorded. None of the patients had donated autologous blood. The patients were examined for blood pressure and heart rate; their body temperature was taken, blood samples were collected for blood cell counts and ion (Na(+), K(+), C1(-)) assessment, and urine samples were collected for laboratory tests. All side-effects and complications during hospitalization were recorded as well as all late consequences. The drainage systems used included Redyrob CAT, Retrans and Bellovac ABT.


RESULTS
In group 1, the median value for total post-operative blood loss was 1065 ml, with the median reinfusion value of 500 ml; 31 % of the patients required homologous blood transfusion. In 36 % of the patients, body temperature increased by more than 1 degrees C, as compared with the value before reinfusion, by 24:00 hours on the operative day, and in 2 % it was higher than 38.5 degrees C. No infection occurred in the early post-operative period, but late infectious complications resulted in reimplantation in one patient (1 %). In group 2, the median value of post-operative blood loss was 1045 ml and all patients received homologous blood transfusion. Post-operative complications directly related to blood reinfusion, such as febrile reaction, shivering, pruritus, blood pressure or heart rate fluctuation, renal failure or coagulopathy, were not recorded in either group.


CONCLUSIONS
The use of drainage system allowed us to reduce the need for homologous blood transfusion by 63 %. Blood salvage reported in the relevant literature varies between 8 and 80 %, which reflects differences in views on lost blood compensation. The total blood loss in both our groups was in agreement with the data reported by other authors, and the same held true for the reinfusion volume; most of the authors recommend to use a maximum of 800 ml. A higher blood volume carries risks due to a high level of free hemoglobin. The recommended period of 6 h for blood reinfusion was respected (to eliminate potential complement activation). We assume that the temperature higher than 38.5 degrees C found in 2 % of our patients was caused by a changed environment and post-operation reactions. The slightly higher losses recorded by 24:00 hours in group 1 were caused, in our opinion, by the resetting of suction pressure after reinfusion had finished. This difference in shed blood was eliminated during the following day and the total losses were comparable in both groups.


CONCLUSIONS
Our results showed that, in total knee arthroplasty, post-operative collection of shed blood and its reinfusion in the circulation can lower the need for homologous blood transfusion and reduce associated risks. If all conditions are observed, i. e., blood reinfusion within 6 h of surgery and the maximum of returned blood not exceeding 800 ml, the method is a safe way of compensating for blood losses in elective knee surgery.
Hendrych
J
J
Ortopedické Oddelení, Krajská Nemocnice Liberec.
D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D016063:Blood Loss, Surgical; D001804:Blood Transfusion, Autologous; D004322:Drainage; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D011184:Postoperative Period