Performance characteristics of a new arterial line filter

Abstract

A new 40 micron polyester screen arterial line filter with integral automatic blood gas separator has been designed with the potential for improved removal characteristics for gas microbubbles and massive air. A simple in vitro evaluation has been carried out comparing the new filter (Pall EC+) against a standard widely-used reference arterial line filter (Pall EC 3840). The filters have been compared in terms of their haemodynamic performance, specifically pressure drop at incremental flow rates and haemolysis characteristics measuring generated plasma free haemoglobin. In addition, the relative abilities of the test and reference filters to remove gaseous microbubbles, and also to vent massive air introduced into the test circuits have been assessed using an ultrasound based microbubble detection system. The results of the studies indicate that the test and reference filters are identical in terms of haemodynamics, with maximal pressure drops of 30 mmHg at 4-5 litres mean flow rate. Neither filter is associated with significant haemolysis in bovine blood test circuits flowing at 4 I/min for 60 minutes. However, the EC+ filter has significantly superior performance over the reference EC 3840 filter in both microbubble removal and in removal of nitrogen gas introduced directly into the test circuit at up to 5 litres gas/min (p < 0.01). The new EC+ filter appears to offer safety in terms of haemodynamics and haemolysis, while providing maximal protection against massive arterial gas embolism.

Get full access to this article

View all access options for this article.

References

Kurusz M. , Scheidner B. , Brown JP , Conti VR Filtration during open-heart surgery: devices, techniques, opinions and complications . Proc Am Acad Cardiovasc Perf 1983; 4: 123-29.

Loop FD , Szabo J. , Rowlinson RD , Urbanek K. Events related to microembolism during extracorporeal perfusion in man: effectiveness of in-line filtration recorded by ultrasound. Ann Thorac Surg 1976; 21(5): 412-20.

Guidoin R. , Taylor KM , Bain WH Blood filter evaluation. Biomat Med Dev Art Org 1977; 5(4): 317-36.

Taylor KM , Devlin BJ , Mittra SM , Wright G. , Brannan JJ Assessment of cerebral damage during open-heart surgery: a new experimental model. Scand J Thorac Cardiovasc Surg 1980 ; 14: 197-203.

Gourlay T. , Taylor KM , Beckett J. Fluid dynamic properties of various arterial line filters. Presented at the Annual Meeting of the Society of Perfusionists of Great Britain and Ireland, 1984.