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Knee: Y. Kalairajah, D. Simpson, A. J. Cossey, G. M. Verrall, and A. J. Spriggins Blood loss after total knee replacement: EFFECTS OF COMPUTER-ASSISTED SURGERY J Bone Joint Surg Br 2005; 87-B: 1480-1482 [Abstract] [Full text] [PDF]

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Blood loss after total knee replacement: effects of computer-assisted surgery

Shashank D Chitgopkar, Simon W Sturdee, Nicholas J London   (17 February 2006)

Blood loss after total knee replacement: effects of computer-assisted surgery

Winston Y Kim   (17 November 2005)

Blood loss after total knee replacement: effects of computer-assisted surgery 17 February 2006
Shashank D Chitgopkar, Senior House Officer Harrogate district hospital, Harrogate, North Yorkshire., Simon W Sturdee, Nicholas J London Send letter to journal: Re: Blood loss after total knee replacement: effects of computer-assisted surgery shashankdc{at}hotmail.com Shashank D Chitgopkar, et al.	Sir, We read this article with great interest. This is the only paper we have seen where blood loss after computer-assisted total knee replacement has been studied. The study is well-organised with a single surgeon carrying out the procedures in one institution, using a uniform approach. The authors mention that all patients were routinely transfused with between one and two units of blood, but there is no mention of the average amount of blood transfused per patient, and whether all the pre-donated blood was utilised. Did any of these patients require allogenic blood transfusion in addition to the pre-donated blood? How much blood was pre-donated by each patient? We find the mean drainage of 1351 ml in the computer-navigated group and 1747 ml in the conventional group to be extremely high compared to our practice of cemented knee replacement. We use one gram of tranexamic acid intravenously at the time of closure and an audit has shown that our average blood drainage is 419 ml, and 684 ml when no tranexamic acid is used. This is similar to other studies in the literature.1,2 The mean drainage in this study is huge in comparison to our experience, and whilst computer-assisted surgery in this study does reduce the blood loss, there are many other proven ways of reducing the transfusion rate in knee replacement surgery.3 S.D. Chitgopkar, D.Orth DNB (Orth) MRCSEd, Senior House Officer, S.W. Sturdee, MRCS MRCSEd FRCS (Tr & Orth), Knee Fellow, N.J. London, MA MD FRCS (Tr & Orth), Consultant Orthopaedic Surgeon, Harrogate District Hospital, Harrogate, UK. 1. Senthil Kumar G, Von Arx OA, Pozo JL. Rate of blood loss over 48 hours following total knee replacement. Knee 2005;12:307-9. 3. Esler CNA, Blakeway C, Fiddian NJ. The use of closed-suction drain in total knee arthroplasty. A prospective randomised study. J Bone Joint Surg [Br] 2003;85-B:215-7. 3. Blood conservation in elective orthopaedic surgery. British Orthopaedic Association. April 2005.
Blood loss after total knee replacement: effects of computer-assisted surgery 17 November 2005
Winston Y Kim, Orthopaedic SpR Hope Hospital, Manchester Send letter to journal: Re: Blood loss after total knee replacement: effects of computer-assisted surgery wjykim{at}hotmail.com Winston Y Kim	Sir, I read this article with great interest. It highlights a potential benefit of computer-assisted total knee replacement, i.e. reduction in total blood loss after routine knee arthroplasty. However, it is difficult to ascertain the potential sources of reduction of blood loss in the computer-assisted group. Surgical operating time was significantly longer in this group, a minimally invasive technique was not used, and additional 4mm bicortical drill holes were required for the placement of tracker pins. Furthermore, a bone plug was used to seal the defect created by the intramedullary rod in the femur in the control group. It is possible that computer-assisted knee replacements used in conjunction with minimally invasive techniques may reduce blood loss after knee replacements but further controlled studies would be required to confirm this hypothesis. W.Y.KIM, Orthopaedic SpR, Hope Hospital, Manchester, UK.