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Background: Autologous platelet-rich plasma (PRP) can be used either to prevent platelets (PLTs) from lesions during extracorporeal circulation or for wound therapy, when processed into PLT gel. The aim of this study was to evaluate the PLT sequestration abilities of a new-generation autotransfusion device.Study Design and Methods: In this experimental study the discontinuous, new-generation autotransfusion device XTRA was evaluated using fresh donor blood. The blood was processed in four different size bowls (X55, X125, X175, X225 [bowls' size in mL]) using the device's built-in "PLT sequestration program." PLT functionality was tested using aggregometry; for PLT activation, β-thromboglobulin (β-TG) and soluble P-selectin levels were determined. Cell damage was assessed by a morphology score and hypotonic shock response. Additionally, PLTs were tested after 6 hours to identify storage lesions.Results: Platelet recovery in the PRP ranged from 39% to 64% and averaged 6.2-fold PLT enrichment as defined by the increase in PLT concentration. The preparation caused minimal cell damage and a decrease in cell function by only 10%, but a slight activation was observed amounting to 9% of the maximal β-TG release. The efficiency of the preparation, represented by the PLT recovery rate, increased in a linear fashion with the increasing bowl sizes being tested. After 6 hours of storage the prepared PLTs showed an additional 9% loss in function, but only 4% decrease in viability.Conclusion: The autotransfusion device XTRA was capable of high-quality perioperative PRP preparation, and the bowl size was found to have an influence on the efficiency of the preparation. [ABSTRACT FROM AUTHOR]

Background: Quantitative neuromuscular monitoring is the gold standard to detect postoperative residual curarization (PORC). Many anesthesiologists, however, use insensitive, qualitative neuromuscular monitoring or unreliable, clinical tests. Goal of this multicentre, prospective, double-blinded, assessor controlled study was to develop an algorithm of muscle function tests to identify PORC. Methods: After extubation a blinded anesthetist performed eight clinical tests in 165 patients. Test results were correlated to calibrated electromyography train-of-four (TOF) ratio and to a postoperatively applied uncalibrated acceleromyography. A classification and regression tree (CART) was calculated developing the algorithm to identify PORC. This was validated against uncalibrated acceleromyography and tactile judgement of TOF fading in separate 100 patients. Results: After eliminating three tests with poor correlation, a model with four tests (r = 0.844) and uncalibrated acceleromyography (r = 0.873) were correlated to electromyographical TOF-values without losing quality of prediction. CART analysis showed that three consecutively performed tests (arm lift, head lift and swallowing or eye opening) can predict electromyographical TOF. Prediction coefficients reveal an advantage of the uncalibrated acceleromyography in terms of specificity to identify the EMG measured train-of-four ratio < 0.7 (100% vs. 42.9%) and <0.9 (89.7% vs. 34.5%) compared to the algorithm. However, due to the high sensitivity of the algorithm (100% vs. 94.4%), the risk to overlook an awake patient with a train-of-four ratio < 0.7 was minimal. Tactile judgement of TOF fading showed poorest sensitivity and specifity at train of four ratio < 0.9 (33.7%, 0%) and <0.7 (18.8%, 16.7%). Conclusions: Residual neuromuscular blockade can be detected by uncalibrated acceleromyography and if not available by a pathway of four clinical muscle function tests in awake patients. The algorithm has a discriminative power comparable to uncalibrated AMG within TOF-values >0.7 and <0.3. Trial registration: Clinical Trials.gov (principal investigator's name: CU, and identifier: NCT03219138) on July 8, 2017. [ABSTRACT FROM AUTHOR]