Diagnosis of acute serious illness: the role of point-of-care technologies

Detecting Stroke at the Emergency Department by a Point of Care Device: A Multicenter Feasibility Study

Purpose

To evaluate if the Strokefinder MD 100 by Medfield Diagnostics AB can be used as a point of care device in overcrowded Emergency Departments (ED).

Patients and Methods

We used the strokefinder MD 100 by Medfield Diagnostics AB in two Greek National Health System (NHS) Hospitals Emergency Departments. Our research protocol was approved by local scientific and ethics committees. We prospectively enrolled 71 adult patients from two NHS emergency departments in whom stroke was included as a differential diagnosis after triage. The feasibility of using the Strokefinder MD 100 by Medfield Diagnostics AB in various emergency department settings was evaluated through a structured questionnaire.

Results

The strokefinder MD 100 was used on 71 patients in various settings in the Emergency Department. In every case, the test was completed at the patient bedside without interfering with other ongoing and diagnostic and resuscitation procedures. There was no additional delay to patient care caused by performing the test when compared with current local Emergency Department practice and protocol. In almost 90% of the cases, a clear result was produced by the device.

Conclusion

The Strokefinder MD 100 can be safely used as a point of care device by all trained healthcare professionals, in the most overcrowded emergency department, in various ED locations.

MeSH terms

Point of Care Systems, Cerebrovascular Stroke, Proof of Concept Study.

The Role of Point-of-Care Testing to Improve Acute Care and Health Care Services

Health care is one of the most important services that need to be provided to any community. Many challenges exist in delivering proper and effective health services, including ensuring timely delivery, providing adequate care through effective management and achieving good outcomes. Point-of-care testing (POCT) plays a crucial role in delivering urgent and appropriate health services, especially in peripheral communities, emergency situations, disaster areas and overcrowded areas. We collected and reviewed secondary data about point-of-care testing from PubMed, Scopus and Google Scholar. Our findings emphasize that POCT provides fast care with minimal waiting time, avoids unnecessary investigations, aids in triage, and provides decision-makers with a clear understanding of the patient's condition to make informed decisions. We recommend point-of-care testing as a frontline investigation in emergency departments, intensive care units, peripheral hospitals, primary health care centers, disaster areas and field hospitals. Point-of-care testing can improve the quality of health services and ensure the provision of necessary health care.

Deep learning on lateral flow immunoassay for the analysis of detection data

Lateral flow immunoassay (LFIA) is an important detection method in vitro diagnosis, which has been widely used in medical industry. It is difficult to analyze all peak shapes through classical methods due to the complexity of LFIA. Classical methods are generally some peak-finding methods, which cannot distinguish the difference between normal peak and interference or noise peak, and it is also difficult for them to find the weak peak. Here, a novel method based on deep learning was proposed, which can effectively solve these problems. The method had two steps. The first was to classify the data by a classification model and screen out double-peaks data, and second was to realize segmentation of the integral regions through an improved U-Net segmentation model. After training, the accuracy of the classification model for validation set was 99.59%, and using combined loss function (WBCE + DSC), intersection over union (IoU) value of segmentation model for validation set was 0.9680. This method was used in a hand-held fluorescence immunochromatography analyzer designed independently by our team. A Ferritin standard curve was created, and the T/C value correlated well with standard concentrations in the range of 0-500 ng/ml (R ² = 0.9986). The coefficients of variation (CVs) were ≤ 1.37%. The recovery rate ranged from 96.37 to 105.07%. Interference or noise peaks are the biggest obstacle in the use of hand-held instruments, and often lead to peak-finding errors. Due to the changeable and flexible use environment of hand-held devices, it is not convenient to provide any technical support. This method greatly reduced the failure rate of peak finding, which can reduce the customer's need for instrument technical support. This study provided a new direction for the data-processing of point-of-care testing (POCT) instruments based on LFIA.

Thoracic, Peripheral, and Cerebral Volume, Circulatory and Pressure Responses To PEEP During Simulated Hemorrhage in a Pig Model: a Case Study

Positive end-expiratory pressure (PEEP) is a respiratory/ventilation procedure that is used to maintain or improve breathing in clinical and experimental cases that exhibit impaired lung function. Body fluid shift movement is not monitored during PEEP application in intensive care units (ICU), which would be interesting specifically in hypotensive patients. Brain injured and hypotensive patients are known to have compromised cerebral blood flow (CBF) autoregulation (AR) but currently, there is no non-invasive way to assess the risk of implementing a hypotensive resuscitation strategy and PEEP use in these patients. The advantage of electrical bioimpedance measurement is that it is noninvasive, continuous, and convenient. Since it has good time resolution, it is ideal for monitoring in intensive care units (ICU). The basis of its future use is to establish physiological correlates. In this study, we demonstrate the use of electrical bioimpedance measurement during bleeding and the use of PEEP in pig measurement. In an anesthetized pig, we performed multimodal recording on the torso and head involving electrical bioimpedance spectroscopy (EIS), fixed frequency impedance plethysmography (IPG), and bipolar (rheoencephalography - REG) measurements and processed data offline. Challenges (n=16) were PEEP, bleeding, change of SAP, and CO2 inhalation. The total measurement time was 4.12 hours. Systemic circulatory results: Bleeding caused a continuous decrease of SAP, cardiac output (CO), and increase of heart rate, temperature, shock index (SI), vegetative - Kerdo index (KI). Pulse pressure (PP) decreased only after second bleeding which coincided with loss of CBF AR. Pulmonary arterial pressure (PAP) increased during PEEP challenges as a function of time and bleeding. EIS/IPG results: Body fluid shift change was characterized by EIS-related variables. Electrical Impedance Spectroscopy was used to quantify the intravascular, interstitial, and intracellular volume changes during the application of PEEP and simulated hemorrhage. The intravascular fluid compartment was the primary source of blood during hemorrhage. PEEP produced a large fluid shift out of the intravascular compartment during the first bleeding period and continued to lose more blood following the second and third bleeding. Fixed frequency IPG was used to quantify the circulatory responses of the calf during PEEP and simulated hemorrhage. PEEP reduced the arterial blood flow into the calf and venous outflow from the calf. Head results: CBF AR was evaluated as a function of SAP change. Before bleeding, and after moderate bleeding, intracranial pressure (ICP), REG, and carotid flow pulse amplitudes (CFa) increased. This change reflected vasodilatation and active CBF AR. After additional hemorrhaging during PEEP, SAP, ICP, REG, CFa signal amplitudes decreased, indicating passive CBF AR. 1) The indicators of active AR status by modalities was the following: REG (n=9, 56 %), CFa (n=7, 44 %), and ICP (n=6, 38 %); 2) CBF reactivity was better for REG than ICP; 3) REG and ICP correlation coefficient were high (R2 = 0.81) during CBF AR active status; 4) PRx and REGx reflected active CBF AR status. CBF AR monitoring with REG offers safety for patients by preventing decreased CBF and secondary brain injury. We used different types of bioimpedance instrumentation to identify physiologic responses in the different parts of the body (that have not been discussed before) and how the peripheral responses ultimately lead to decreased cardiac output and changes in the head. These bioimpedance methods can improve ICU monitoring, increase the adequacy of therapy, and decrease mortality and morbidity.