There are multiple documented advantages of undertaking total knee arthroplasty (TKA) without tourniquet, however, increased rates of blood loss and transfusion are often cited as contraindications to this approach. The aim of this study was to examine the effect of intra-operative TA administration on blood loss and transfusion rates in TKA without pneumatic tourniquet, using Rivaroxaban as thrombo-embolic prophylaxis. 120 patients split into two continuous data sets, (A+B), underwent TKA without application of above knee tourniquet, receiving a post operative dose of oral Rivaroxaban within 8 hours. Group B patients received an intra-operative dose of 1 gram of Tranexamic Acid intravenously before the first cut, whilst those in group A did not. Haemoglobin and haematocrit levels were recorded peri-operatively. A revised Gross formula was used to calculate blood loss. Four patients were excluded from the study for incomplete data.Background
Method
Blood tests including liver function tests (LFTs), C-reactive protein (CRP), coagulation screens and international normalising ratios (INR) are frequently requested investigations that complement the surgical and anaesthetic pre-operative assessment of patients. The paucity of guidance available for blood requesting in acute trauma and orthopaedic admissions can lead to inappropriate requesting practices and over investigation. Unnecessary tests place an economic burden on a hospital and repeated venepuncture is unpleasant for patients. We audited blood requesting practices and with multidisciplinary input developed guidelines to improve practice which were subsequently implemented. Admissions over a period of one month to Ninewells Hospital and Perth Royal Infirmary were audited retrospectively. The frequency and clinical indications for LFTs, coagulation screens/INR and CRP for the duration of the patient's admission were recorded. Re-audit was carried out for one month after the introduction of the guidelines. 216 patients were included in January and 236 patients in September 2014. Total no. of LFTs requested: January 895, September 336 (−62.5%). Total no of coagulation screens/INR requested: January 307, September 210 (−31.6%). Total number of CRPs requested: January 894, September 317 (−64.5%). No. of blood requests per patient: January (M=4.81, SD 4.75), September (M=3.60, SD = 4.70). A significant decrease was observed in admission requesting and subsequent monitoring (p<0.01) for LFTs, coagulation screens/INR, CRP when the guidance was introduced. The implementation of the bloods guidance resulted in a large reduction in admission requesting and subsequent monitoring without incident. The cost of investigation was significantly reduced, as were venepuncture rates.
