The goal of this project is to develop and validate a hand-held sensor for the rapid and comprehensive assessment of coagulation status in patients. Impaired blood coagulation or coagulopathy, results from several conditions associated with severe trauma, surgery or illness, and can cause life-threatening bleeding or thrombotic disorders. Deficient coagulation can lead to 'hypocoagulable' states resulting in uncontrolled bleeding, which may cause severe anemia, shock and multiple organ failure. In other cases, coagulation defects may manifest as 'hypercoagulable' states, causing increased clotting that can result in potentially fatal complications such as deep vein thrombosis and pulmonary embolism. During surgery, trauma care and chronic disease management, clinicians often encounter the challenging task of maintaining a precarious balance between bleeding and coagulation. In order to achieve optimal outcome, the early detection of coagulation defects and coagulation monitoring during therapy is therefore essential. Unfortunately, the diagnosis and treatment monitoring of impaired coagulation is currently problematic because of the long turn-around time of standard laboratory tests. Our proposal directly addresses the unmet clinical need to develop and translate a hand-held, portable coagulation sensor, termed Optical Thromboelastography (OTEG) for point of care use. The technique involves placing a few drops of blood in a small cartridge. A laser source illuminates the blood sample and a CMOS camera images laser speckle patterns reflected from the sample over time. By analyzing laser speckle intensity fluctuations in real-time, we can measure blood viscoelastic properties during coagulation and recover information about multiple coagulation metrics. The OTEG device will also provide the capability to measure platelet aggregation in real- time to diagnose impaired platelet function in patients. As a result, using a single portable device with a few drops of blood, OTEG can achieve the comprehensive assessment of multiple parameters: clotting time, clot viscoelasticity and formation rate, fibrinogen, fibrinolysis and platelet function, within a few minutes. To validate the device, we wil perform studies to test the accuracy of OTEG via comparison with standard thromboelastography and laboratory tests. In the final phase of our work, we will conduct a clinical study to evaluate the utility of OTEG for coagulation monitoring in patients at the point f care.
Impaired blood coagulation is a leading cause of preventable death following acute trauma and major surgery. The clinical management of coagulation defects is often problematic due to the long turn-around time for laboratory-based coagulation testing. By permitting the quantification of blood coagulation status in real-time at the point-of-care, the OTEG device developed in this proposal will advance clinical capability for the timely detection and treatment of coagulation defects, ultimately improving patient outcome.
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| Hajjarian, Zeinab; Tripathi, Markandey M; Nadkarni, Seemantini K (2015) Optical Thromboelastography to evaluate whole blood coagulation. J Biophotonics 8:372-81 |
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| Hajjarian, Zeinab; Nadkarni, Seemantini K (2014) Correction of optical absorption and scattering variations in Laser Speckle Rheology measurements. Opt Express 22:6349-61 |
| Hajjarian, Zeinab; Nadkarni, Seemantini K (2013) Evaluation and correction for optical scattering variations in laser speckle rheology of biological fluids. PLoS One 8:e65014 |
