Utility of gas inlet pressure monitoring in extracorporeal membrane oxygenation.

PURPOSE: Purpose: Condensation that clogs the hollow fibers of the oxygenation and accumulation of plasma leaks reduces oxygenated lung capacity. In this study, artificial We evaluated whether monitoring changes in lung gas inlet pressure was a way to predict these complications. METHODS: Changes in gas inlet pressure and oxygenation capacity of three different prostheses (BIOCUBE6000, EXCELUNG PRIME, and Capiox-LX) Evaluated the relationship. When simulating plasma leakage using BIOCUBE6000, sodium dodecyl sulfate (SDS) (1%, 0.1%, A solution of 0.01%, and RO water) reduced surface tension. During 120 minutes of circulation, changes in gas inlet pressure and leakage from the membrane into the gas flow path The amount of fluid was measured. RESULTS: There was a significant negative correlation between the gas inlet pressure changes and the oxygenation capacity of all three oxygenators (BIOCUBE6000: R2 = 0.957, EXCELUNG PRIME: R2 = 0.946, Capiox-LX: R2 = 0.878). After 120 min of SDS solution circulation using the BIOCUBE6000, both the gas inlet pressure and the volume of fluid leaking from the membrane into the gas flow path increased in proportion to the SDS solution concentration: RO water (0.56 ± 0.11 mmHg and 16.67 mL ± 0.94 mL), 0.01% SDS (0.98 ± 0.11 mmHg and 23.3 ± 0.47 mL,) 0.1% SDS (1.64 ± 0.21 mmHg and 29.0 ± 1.63 mL), and 1%SDS (14.3 ± 0.27 mmHg and 36.7 ± 0.47 mL) (n = 3). CONCLUSION: This study confirmed that monitoring the gas inlet pressure changes of an oxygenator during ECMO is clinically useful.

Real-Time Measurement of Polyvinylpyrrolidone Eluted from Polysulfone Membrane Dialyzers Based on the Ultraviolet Spectrum.

The objective of this study was to develop a new method for measuring polyvinylpyrrolidone (PVP) eluted from polysulfone (PSu) membrane dialyzers. The Müller method is generally used for the measurement of PVP, in which the PVP concentration is determined by measuring the absorbance after a red color is generated by the formation of PVP-iodine complexes when iodine is added to a sample. In contrast, our method does not require any reagents and allows real-time measurement of PVP by the ultraviolet absorption spectrum (UV-s method). In this study, the UV-s method and the Müller method were used to measure PVP eluted from two types of PSu membrane dialyzer (PS-1.6UW sterilized by autoclaving [n = 10] and APS-15SA sterilized by gamma radiation [n = 10]). Polyvinylpyrrolidone concentrations measured by the two methods showed a significant positive correlation (rs = 0.99, p = 0.0006). The PVP concentration (median [25th-75th percentiles]) in PS-1.6UW dialyzer washings obtained by rinsing with physiologic saline was 2.0 (1.18-4.85) mg/L with the Müller method and 3.35 (2.38-4.23) mg/L with the UV-s method, showing no significant difference. However, the PVP concentration in APS-15SA dialyzer washings was 0 (0-0.35) mg/L by the Müller method and 0.95 (0.45-2.58) mg/L by the UV-s method, and there was a significant difference between the two methods. In conclusion, the low concentration of PVP eluted from a PSu dialyzer sterilized by gamma radiation was hardly detected by the Müller method but could be clearly detected by the new UV-s method. These findings suggest that the UV-s method could be used for real-time measurement of PVP eluted from PSu membrane dialyzers.

Influence of Sterilization and Storage Period on Elution of Polyvinylpyrrolidone from Wet-Type Polysulfone Membrane Dialyzers.

The objectives of this study were to investigate the influence of the sterilization and storage period on elution of polyvinylpyrrolidone (PVP) from wet-type polysulfone (PSu) membrane dialyzers. APS-15SA (APS) dialyzers sterilized by gamma-radiation and RENAK PS-1.6 (RENAK) dialyzers sterilized by autoclaving were compared in this study. Each dialyzer was washed with physiological saline and the amount of PVP eluted from the PSu membrane was measured. Then, experimental use of each dialyzer was performed by circulating physiological saline for 4 hours, after which the PVP eluted from the PSu membrane was measured. As the results, the amount of PVP eluted by washing was positively correlated with the storage period for both dialyzers (APS: rs = 0.958; RENAK: rs = 0.952). In the experimental circuit, the amount of PVP eluted from the RENAK dialyzer was positively correlated with the storage period (rs = 0.810), whereas the amount of PVP eluted from the APS dialyzer was negatively correlated with the storage period (rs = -0.833). We found that the amount of PVP eluted from PSu membrane is quite different by the sterilization and storage period of dialyzers.

A case of Wegener's granulomatosis with pulmonary bleeding successfully treated with double filtration plasmapheresis (DFPP).

We report a case of a 41-year-old Japanese man who presented with rapidly progressive glomerulonephritis, chronic sinusitis, and positive cytoplasmic-antineutrophil cytoplasmic antibody (c-ANCA). Renal biopsy showed crescentic glomerulonephritis, and he was diagnosed as having Wegener's granulomatosis. During the clinical course, he suffered from pulmonary bleeding, and combination therapy of steroid, immunosuppressant, and double filtration plasmapheresis (DFPP) was started. He rapidly entered remission after assistance through DFPP, suggesting the potential efficacy of DFPP for Wegener's granulomatosis, especially with pulmonary bleeding.