Zu Entstehungsmechanismen von Plasma Leakage in mikroporösen Kapillarmembranoxygenatoren

Plasma leakage (PL) is a particular problem of microporous membrane oxygenators. It is described as the migration of blood plasma through the micropores into the gas compartment. In this dissertation, in-vitro-studies, wettability measurements, and electron microscope photos of microporous hollow fibres were used to gain a deeper understanding of the conditions necessary for the occurrence of a PL. These investigations were substantiated by studies during extracorporeal long-term perfusion in sheep and in the clinical use of oxygenators. Neither in the in-vitro circuits with miniaturized oxygenator modules, nor in the sheep studies, a significant PL was monitored. In some cases, amino acids were detected in the transferred liquid (the condensate that was collected at the gas outlet). The composition of the amino acids indicated the transition of albumin or albumin fragments. This malfunction of oxygenators was called leakage-similar-event. In the clinical use of oxygenators, the transferred liquid was examined with urine test stripes. The amount of detected proteins was much higher than in the in-vitro or animal studies. In addition, glucose and haemoglobin were detected. In this case, the oxygenator malfunction was called preleakage, because it was irreversible and terminated in a manifest PL. The electron microscope photos of unused hollow fibres revealed defects and disruptions as a possible reason for PL and leakage-similar events. In laboratory examinations the surface energy of different types of microporous hollow fibres prior to and after human blood contact was determined. The results indicated that the surface energy of all fibres was increased after the blood contact. From the increased wettability of the fibres an increased risk for PL can be deduced. An analysis of oxygenator fibres after long-term perfusion with the electron microscope revealed a high amount of blood compounds on the microporous fibre surface. The results of the presented investigations show that the interaction of blood compounds with the microporous fibre surface and the associated alteration of wettability of very high importance for the occurrence of PL.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2004

Author dc:creator

• Wien, Sabine Maria

Contributors dc:contributor

• Mottaghy, Khosrow

• info:eu-repo/classification/ddc/610
• Medizin
• Plasma Leakage
• mikroporöse Membranen
• Kapillarmembranoxygenatoren
• Prä-Leakage
• Oberflächenenergie
• Oberflächenspannung
• Aminosäuren

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-121309%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:59530