Analytical accuracy and precision of two novel Point-of-Care systems for INR determination

Microfluidics in Haemostasis: A Review

Haemostatic disorders are both complex and costly in relation to both their treatment and subsequent management. As leading causes of mortality worldwide, there is an ever-increasing drive to improve the diagnosis and prevention of haemostatic disorders. The field of microfluidic and Lab on a Chip (LOC) technologies is rapidly advancing and the important role of miniaturised diagnostics is becoming more evident in the healthcare system, with particular importance in near patient testing (NPT) and point of care (POC) settings. Microfluidic technologies present innovative solutions to diagnostic and clinical challenges which have the knock-on effect of improving health care and quality of life. In this review, both advanced microfluidic devices (R&D) and commercially available devices for the diagnosis and monitoring of haemostasis-related disorders and antithrombotic therapies, respectively, are discussed. Innovative design specifications, fabrication techniques, and modes of detection in addition to the materials used in developing micro-channels are reviewed in the context of application to the field of haemostasis.

Development of Multidisciplinary Anticoagulation Management Guidelines for Patients Receiving Durable Mechanical Circulatory Support

Patients receiving durable mechanical circulatory support (MCS) require life-long anticoagulation with a vitamin K antagonist (VKA). Due to alternations in hemostasis, concomitant therapy with antiplatelet agents and critical illness, they are at increased risk of thromboembolic and bleeding complications compared with the general population managed on VKAs. To prevent thrombotic events, current guidelines recommend that patients with MCS receive long-term anticoagulation with a VKA to maintain a target international normalized ratio (INR) as specified by device manufacturers, but limited data exist regarding specific routine management of anticoagulation therapy and its potential complications. To optimize anticoagulation management and minimize risk in these patients, we have centralized anticoagulation management in a collaborative approach between the inpatient hemostatic and antithrombotic (HAT) stewardship service and between ambulatory anticoagulation management service (AMS) and the advanced heart disease team. Patients are followed by these three services beginning when the device is implanted and extending the duration that patients have the device. The teams include multiple clinicians from cardiac surgery, cardiology, hematology, pharmacy, nursing, case management, nutrition, and psychiatry, therefore, in order to standardize practice among clinicians without compromising patient centered decision making, we assembled an interdisciplinary team to create multiple treatment guidelines. In addition to a centralized and collaborative approach, our guidelines ensure seamless transitions of care between the inpatient and outpatient settings. We believe our approach has demontrated a positive improvement in the care of these challenging patients. In this article, we present our comprehensive centralized anticoagulation management approach for patients with left ventricular assist systems (LVAS).

Coagulation measurement from whole blood using vibrating optical fiber in a disposable cartridge

In clinics, blood coagulation time measurements are performed using mechanical measurements with blood plasma. Such measurements are challenging to do in a lab-on-a-chip (LoC) system using a small volume of whole blood. Existing LoC systems use indirect measurement principles employing optical or electrochemical methods. We developed an LoC system using mechanical measurements with a small volume of whole blood without requiring sample preparation. The measurement is performed in a microfluidic channel where two fibers are placed inline with a small gap in between. The first fiber operates near its mechanical resonance using remote magnetic actuation and immersed in the sample. The second fiber is a pick-up fiber acting as an optical sensor. The microfluidic channel is engineered innovatively such that the blood does not block the gap between the vibrating fiber and the pick-up fiber, resulting in high signal-to-noise ratio optical output. The control plasma test results matched well with the plasma manufacturer's datasheet. Activated-partial-thromboplastin-time tests were successfully performed also with human whole blood samples, and the method is proven to be effective. Simplicity of the cartridge design and cost of readily available materials enable a low-cost point-of-care device for blood coagulation measurements.