Some of the current drawbacks in patient diagnosis and following treatment result from the need to perform lab tests only by centralized laboratories. Due to overcrowded healthcare system there is need for rapidly decentralizing diagnostics as providers seek to improve clinical outcomes and allow for more efficiently use of hospital resources. The implementation of new technologies designed for the point of care (POC), can potentially improve clinical diagnosis, accelerates the initiation of treatment and improve clinical outcome.
The main goal of POC testing, defined as testing at or near the site of patient care, is to improve medical and economic outcomes by promoting rapid response and faster turnaround time (TAT) of test results (1). When utilized effectively this decrease in TAT can help in expediting medical decision-making and translate into measurable improvements in clinical care and throughput, benefiting both the patient and the health care institution. Additionally, decreased sample sizes can be advantageous in patient groups where obtaining substantial amounts of blood might be difficult or potentially harmful, for example in children, elderly people, or those in intensive care (2).
It has been established in previous studies which compared the use of POC platforms with central lab traditional analyzers, that the latter delayed physician’s treatment decisions, required larger blood volumes for testing and raised the probability for complications during blood sampling. It was also demonstrated that the implementation of POC clinical diagnostics in patient vicinity can speed up the process from assessment to treatment leading to an improvement of healthcare quality and better clinical outcomes.
Increasing numbers of Emergency Departments (ED's), surgical and inpatient wards, as well as oncology and community clinics are incorporating POCT in clinical settings to expedite the preanalytical testing phase, which translates to shorter waiting times, increased workflow efficiency and improved timeliness of patient management without need for highly trained operators.
At present, a multi-parametric Complete Blood Count (CBC) analysis, with or without leukocyte differentiation, is generally restricted to the clinical laboratory relying on highly automated and complexed hematology analyzers. A true POC hematology platform has been widely recognized as an unmet need.
A hematology analyzer at the poor-resource settings such as primary care or prehospital emergency care could aid in identifying and monitoring a variety of acute and chronic conditions such as anemia, sepsis and dehydration (3)-(5). A CBC with differential may also help clinicians to distinguish between viral and bacterial source of infection, therefore serving as a decision factor in prescribing antibiotics (6).
On a similar note a CBC test at the emergency room or at the operating theatre, where time factor is critical, may play an important role in determining whether an expensive stay is required at all, and if rapid transfusion is required.
To address the clinical and economical requirement for a cell-based POC analyzer, PixCell Medical has developed the HemoScreen, a POC system integrating flow cytometry and digital imaging in a single platform. Using capillary or venous whole blood the HemoScreen is capable of performing a multi-parametric CBC testing, including measurement of RBC and its indices, HGB content, PLT enumeration, and WBC count with 5-part differential, as well as morphological abnormalities flagging. The system solution is based on the HemoScreen digital image analyzer and a disposable ready for use sample cartridge. Sample acquisition and manipulation are automatically performed within the cartridge, facilitating its simple operation and preempting pre-analytical errors. By employing a novel method called viscoelastic focusing, cells are precisely focused in a single plane, enabling their digital imaging and subsequent analysis. With direct imaging, it is possible to make sources of analytical and post-analytical error harmless or occur at negligible rates.
References
1. Principles and practice of point-of-care testing. Kost GJ et al, 2002.
2. The state of point-of-care testing: a European perspective. Larsson A et al, 2015.
3. Current and future use of point-of-care tests in primary care: an international survey in Australia, Belgium, The Netherlands, the UK and the USA.Howick J, et al 2014.
4. A Niche for Microfluidics in Portable Hematology Analyzers. Heikali D, Di Carlo D, 2010.
5. Utility of the white blood cell count to predict the need for admission in adults presenting to the emergency department with undifferentiated abdominal pain. Bacus S et al, 2004.
6. A comparison of 2 white blood cell count devices to aid judicious antibiotic prescribing. Casey JR, Pichichero ME, 2009.
7. Rapid testing of red blood cells, white blood cells and platelets in intensive care patients using the HemoScreen™ point-of-care analyzer. Larsson A et al, 2018.
8. The HemoScreen, a novel haematology analyser for the point of care. Ben-Yosef et al, 2015.
9. Rapid testing of red blood cell parameters in primary care patients using HemoScreen™ point of care instrument. Karawajczyk M et al 2019 (In press).
