In this study we have established normal values, reliability, and clinical applicability of CHEPs in SFN.

Assays based on the formation of thrombin and fibrin are frequently used, and results are considered exchangeable in research/clinical settings. However, thrombin generation and fibrin formation do not always go hand in hand and flow profoundly influences thrombus formation. We describe the technical/clinical evaluation of an assay to simultaneously measure thrombin generation and fibrin formation under conditions of flow. Introduction of a fluorometer into a 'cone and base principle'-based rheometer allowed the measurement of thrombin generation (using a thrombin-sensitive substrate) and fibrin formation (changes in viscosity), while applying a linear shear flow. Increasing shear rates inversely related with thrombin generation and fibrin formation. Increasing fibrinogen concentrations in defibrinated plasma resulted in increased thrombin generation and fibrin formation. In pre-operative samples of 70 patients undergoing cardiothoracic surgery, fibrin formation and thrombin generation parameters correlated with fibrinogen content, rotational thromboelastometry (ROTEM) and whole blood Calibrated Automated Thrombinography (CAT) parameters, respectively. Upon dividing patients into two groups based on the median clot strength, a significant difference in perioperative/total blood loss was established. In conclusion, we clinically evaluated a method capable of simultaneously measuring thrombin generation and fibrin formation in plasma/whole blood under continuous flow, rendering our method one step closer to physiology. Importantly, our test proved to be indicative for the amount of blood loss during/after cardiothoracic surgery.

Background: Measuring thrombin generation (TG) in plasma increasingly gained attention as a diagnostic tool in the field of thrombosis and hemostasis. To include the contribution of all blood cells, recently, the whole blood TG method was developed. Methods: We changed the calculation method of the standard calibrated automated thrombography (CAT) to a method only taking into account the data until the peak of TG, thereby considerably reducing the time from blood draw to result. By redesigning the method, the blood volume per test was reduced to 15 μL. Results: For all TG parameters, the interassay variation proved to be below 15%. The interindividual variation of all parameters was comparable to the CAT method. Thirty-three patients undergoing cardiothoracic surgery were included to investigate whether our assay correlates with postoperative blood loss. On dividing patients into severe and mild bleeders, significant differences between both groups were found for the peak endogenous thrombin potential (peakETP) and peak values determined by our near-patient device. Importantly, patients with a peakETP below the median experienced significantly more blood loss compared to those with a peakETP above the median. A similar division based on the peak as well as the body mass index of the patient yielded similar significant differences. A combination of the peakETP, the body mass index, and the lag time even resulted in a better predictor of blood loss compared to each parameter separately. Conclusions: Our adapted whole blood TG assay can be used near patients and is indicative for the amount of blood loss post cardiothoracic surgery.

Objective Objective of this case report is to draw attention to a less known thrombotic complication associated with COVID-19, i.e., thrombosis of both radial arteries, with possible (long-term) consequences. The Case In our COVID-19 ICU a 49-year-old male patient was admitted, with past medical history of obesity, smoking and diabetes, but no reported atherosclerotic complications. The patient had been admitted with severe hypoxemia and multiple pulmonary emboli were CT-confirmed. ICU-treatment included mechanical ventilation and therapeutic anticoagulation. Preparing the insertion of a new radial artery catheter for invasive blood pressure measurement and blood sampling, we detected that both radial arteries were non-pulsating and occluded: (a) Sonography showed the typical anatomical localization of both radial and ulnar arteries. However, Doppler-derived flow-signals could only be obtained from the ulnar arteries. (b) To test collateral arterial supply of the hand, a pulse-oximeter was placed on the index finger. Thereafter, the ulnar artery at the wrist was compressed. This compression caused an immediate loss of the finger's pulse-oximetry perfusion signal. The effect was reversible upon release of the ulnar artery. (c) To test for collateral perfusion undetectable by pulse-oximetry, we measured regional oxygen saturation (rSO 2) of the thenar muscle by near-infrared spectroscopy (NIRS). Confirming our findings above, ulnar arterial compression demonstrated that thenar rSO 2 was dependent on ulnar artery flow. The described development of bilateral radial artery occlusion in a relatively young and therapeutically anticoagulated patient with no history of atherosclerosis was unexpected. Conclusions Since COVID-19 patients are at increased risk for arterial occlusion, it appears advisable to meticulously check for adequacy of collateral (hand-) perfusion, avoiding the harm of hand ischemia if interventions (e.g., catheterizations) at the radial or ulnar artery are intended.

Background Frailty is a multidimensional condition characterized by loss of functional reserve, which results in increased vulnerability to adverse outcomes following surgery. Anesthesiologists can reduce adverse outcomes when risk factors are recognized early and dedicated care pathways are operational. As the frail elderly population is growing, we investigated the perspective on the aging population, familiarity with the frailty syndrome and current organization of perioperative care for elderly patients among Dutch anesthesiologists. Methods A fifteen-item survey was distributed among anesthesiologists and residents during the annual meeting of the Dutch Society of Anesthesiology. The first section included questions on self-reported competence on identification of frailty, acquaintance with local protocols and attitude towards the increasing amounts of elderly patients presenting for surgery. The second part included questions on demographic features of the participant such as job position, experience and type of hospital. Answers are presented as percentages, using the total number of replies for the question per group as a denominator. Results A sample of 132 surveys was obtained. The increasing number of elderly patients was primarily perceived as challenging by 76% of respondents. Ninety-nine percent agreed that frailty should influence anesthetic management, while 85% of respondents claimed to feel competent to recognize frailty. Thirty-four percent of respondents reported the use of a dedicated pathway in the preoperative approach of frail elderly patients. However, only 30% of respondents reported to know where to find the frailty screening in the patient file and appointed that frailty is not consistently documented. Interestingly, only 43% of respondents reported adequate collaboration with geriatricians. This could include for example a standardized preoperative multidisciplinary approach or dedicated pathway for the elderly patient. Conclusions This survey demonstrated that the increasing number of frail elderly patients is perceived as important and relevant for anesthetic management. Opportunities lie in improving the organization and effectuation of perioperative care by more consistent involvement of anesthesiologists.