Tranexamic acid (TEA), an antifibrinolytic agent, is routinely used for reduction of blood loss in total hip arthroplasty (THA). However, use of intravenous (IV) TEA has been questioned due to safety concerns and a lack of biochemical data in the arthroplasty literature. Tranexamic acid given topically as a periarticular solution is a promising alternative route of administration. The purpose of this study is to identify differences in systemic absorption for intravenous and topical TEA administered during primary THA. In a blinded randomised controlled trial of patients undergoing primary cementless total hip arthroplasty, 29 participants received a weight-based bolus infusion of intravenous TEA (20 mg/kg) 10 minutes prior to skin incision. Conversely, 15 participants received a 1.5 g bolus dose of TEA administered topically into the periarticular region of the operative hip at the time of arthrotomy closure. A blood sample was drawn one hour post-administration for measurement of serum TEA concentration (µg/mL) by tandem mass spectrometry. In addition to comparing mean concentration levels for both treatment arms, each sample concentration was referenced to a pre-determined TEA concentration threshold of 10 µg/mL, a value known to represent 80% tissue plasminogen activator (tPA) inhibition Those participants receiving topical TEA had four-fold lower TEA levels at one hour postoperatively (mean 12.44 ± 17.59 versus 52.54 ± 23.94 µg/mL, p<0.05). These results demonstrate significantly lower circulating TEA at one hour after topical administration. Intravenous TEA must travel through the intravascular compartment in order to reach the operative hip. Topical administration of TEA targets bleeding tissues within the surgical field without necessitating parenteral administration. This results in less inhibition of tPA away from the operative site, potentially decreasing the risk of developing a pro-thrombotic state postoperatively. Correlating these results with outcomes from clinical efficacy trials comparing intravenous and topical TEA use in THA will further clarify optimal dosing strategies.
Total joint arthroplasty is commonly associated with post-operative anemia. Blood conservation programs have been developed to optimise patients prior to surgery. Epoetin Alfa (Eprex) or intravenous (IV) iron transfusions are two modalities that can be used pre-operatively to optimise hemoglobin and ferritin levels. There are, however, potential complications and increased costs associated with their use. Oral iron is a less costly option for those undergoing surgery but requires more time to take effect. There are no studies to date that examine the effects of an early screening program utilising oral iron supplementation prior to total joint arthroplasty. The purpose of this study is to evaluate the effect of implementing early pre-operative oral iron supplementation on patients prior total joint arthroplasty. A retrospective review of patients undergoing total joint arthroplasty was performed using our institution clinical informatics database. We identified all patients seen in pre-admission clinic (PAC) between Jan 1, 2009 and March 31, 2010 representing our control group. We then identified all patients seen in PAC between October 1, 2012 and December 31, 2013. Patients in this cohort received screening blood work when booked for surgery, and oral iron supplementation was given to patients with hemoglobin of less than 135g/L or ferritin less than 100ug/L, thus representing our treatment group. Patients undergoing revision, uni-compartment knee arthroplasty and bilateral arthroplasties were excluded from the study. Pearson Chi-Square tests were used to calculate significance between groups with main outcomes including pre-admission hemoglobin, and pre-operative requirements for Eprex or IV iron. In our control group, we identified 354 patients (25.6%) with hemoglobin less than 130 g/L at time of pre-admission clinic. In our treatment group, this number dropped significantly to only 16.4% of patients (p<0.005). Implementation of an early screening program using oral iron supplementation resulted in a decrease in the number of patients with hemoglobin lower than 130 g/L at the time of pre-admission clinic. There was also a significant decrease in the use of Eprex and IV iron pre-operatively in the patients in the early screening program. These results encourage the use of early oral iron supplementation for patients with hemoglobin less than 135 g/L or ferritin less than 100ug/L in order to optimise patients prior to total joint arthroplasty.
