Microbial colonization of the Groningen speaking valve and its relationship to valve failure.

Abstract

Speaking valve failure may be related to biofilm development. An inter-observer validated method of assessing microbial overgrowth in defective prostheses was developed. Two independent observers recorded colonisation of the valves on a 100 mm linear analogue scale in several defined areas. Inter-observer agreement was high in all areas. In vitro opening pressure and derived forward resistances were measured. The relationship between colonization of the valves and the in vitro measurements was investigated. Significant correlations for a two-tailed Spearman's test were recorded between the resistance and microbial colonization of the hinge and oesophageal areas (rs 0.22: P < 0.05, rs 0.25: P < 0.05, n = 80). There was no significant association for resistance and colonization of the tracheal surface, and no significant association between the opening pressure and the colonization. This work suggests that microbial colonization of the prosthesis in the oesophageal and hinge areas is associated with valve failure.