Background: A growing body of evidence has shown Tranexamic Acid (TXA) is effective in decreasing perioperative blood loss and transfusion requirements in both primary and revision joint arthroplasty. TXA is a synthetic drug which limits blood loss through inhibition of fibrinolysis and clot degradation. It helps reduce requirement of colloids and crystalloids and hence provides better haemodynamic stability. The aim of this study was to detect the effect of tranexamic acid on coagulation parameters and effect on bleeding in knee replacement surgeries performed under tourniquet.Methods: Patients undergone surgeries of Total Knee Replacement (TKR) performed under tourniquet were included in the study. A single dosage of 20 mg/kg per body weight of tranexamic acid was administered after application of a tourniquet. Three times blood sample was collected, and coagulation parameters were recorded and compared. The first sample was collected at the time of TXA injection and application of a tourniquet, second after 4 hours and third after 24 hours post TXA injection. Coagulation parameters noted were analyzed using Statistical analysis by SPSS software. All parameters were compared in relation to baseline i.e. at the time of TXA injection.Results: On comparison of demographic profile, morbidity, sofa score and hemodynamic parameters there was the insignificant difference (P > 0.05). Repeated measures of ANOVA at 95% Confidential Interval P value was 0.000 which is less than the significant level that is 0.05 so that value of Platelet Function (PF), Activated Coagulation Time (ACT) and Clot Rate (CR) at 0 hrs, 04 hrs and 24 hrs was statistically significant. Correlation between blood loss and difference of the value of ACT at 0 hrs and 04 hrs is a small negative correlation but statistically nonsignificant (P value is 0.359).Conclusions: After TXA administration there is a change in coagulation parameters like an Activated Coagulation Time (ACT), Platelet Function (PF), and Clot Rate (CR) measured at three intervals, hence it can be a guide to detect early derangement in the coagulation profile in a patient undergoing knee replace surgery. TXA correlation between blood loss with changes in parameters of coagulation i.e. ACT, PF and CR were noted but not significant.

Background: In critically ill patients in the intensive care unit (ICU), early aggressive fluid replacement is the cornerstone of resuscitation. Traditionally employed static measures of fluid responsiveness have a poor predictive value. It is therefore imperative to employ dynamic measures of fluid responsiveness that take into account the heart lung interactions in the mechanically ventilated patients. The main objective of this study was to evaluate the reliability of one such non-invasive dynamic index: Plethysmographic variability index (PVI) compared to the widely employed Inferior vena cava distensibility index (dIVC).Methods: Seventy-six adult patients admitted at a tertiary care mixed ICU, who developed hypotension (MAP<65mmHg), were included in the study. PVI was recorded using the MASIMO-7 monitor and dIVC measurements done using Terason ultrasound. Based on the dIVC measurement threshold of 18%, the patients were classified into volume responders and non-responders. The hemodynamic, PVI and dIVC measurements were recorded at pre specified time points following a fluid challenge of 20 ml/kg crystalloid infusion.Results: Baseline PVI values were significantly higher in the responders (22.3±8.2) compared to non-responders (10.1±2.9) (p<0.001) and showed a declining trend at all time points in the responders. Similar declining trend was observed in the dIVC measurements. Overall, the Pearson correlation graph showed strong correlation between dIVC and PVI values at all time points (r=0.678, p=0.001). The ROC curve between the dIVC and PVI values revealed that Baseline PVI (Pre PVI) >15.5% discriminated between responders and non-responders with a 90.2% sensitivity and 75% specificity with an AUC of 0.84 (0.72-0.96) (p<0.001).Conclusions: There is good correlation between PVI values and measured dIVC values at baseline and following a fluid challenge. Thus, PVI may be an acceptable, real time, continuous, surrogate measure of fluid responsiveness in critically ill patients.