The Miller tracheal cuff pressure control valve

Abstract

SummaryA constant pressure differential valve for the control of tracheal tube cuff pressure was tested under clinical conditions. Fifty-one patients underwent controlled ventilation and 20 patients were allowed to breathe spontaneously. Nitrous oxide 66% with oxygen 33% and halothane were used via a circle system. With controlled respiration at afresh gas flow of 3-10 Imin -', the expiratory cuff pressures of 10.1-16 cmH20 and the inspiratory cuffpressures of 23.4-32.4 cmH,O were below venous and arterial mucosal capillary perfusion pressures respectively. Cuff pressures were unaltered with time. Methylene blue instilled into the larynx did not appear in the trachea. Fifty-two control patients had the same incidence of sore throat (40%) and hoarseness (30%) at 24 h. With spontaneous ventilation, fresh g a s j o w s of 5-15 Imin-' maintained the cuff pressure above 10 cmH20. We conclude that this valve prevents excessive tracheal cuff pressure while maintaining the airway seal.

Pediatric airway anatomy may not be what we thought: implications for clinical practice and the use of cuffed endotracheal tubes

“…Numerous methods and devices have been employed to measure, monitor, and regulate the intracuff pressure . In some of the devices, a detachable device is attached to the pilot balloon which not only monitors the intracuff pressure, but also acts as a ‘pop‐off’ valve to regulate pressure at or below a preset value .…”

A technique to measure the intracuff pressure continuously: an in vivo demonstration of its accuracy

“…Numerous methods and devices have been employed to measure, monitor, and regulate the intracuff pressure. In many of these, a detachable device is attached to the pilot balloon to monitor and/or regulate the intracuff pressure (15)(16)(17)(18)(19)(20)(21)(22)(23)(24). Other attempts to improve the safety margin have included modifications of the design of the cuff, the ETT, and inflation of the cuff with agents other than air (25)(26)(27)(28)(29)(30)(31)(32).…”

Cuffdruckmessung und Regelung im Erwachsenenalter

“…Häufig erfolgt im klinischen Alltag auch gar keine Druckregulierung [22].Daneben sind diverse selbstkonstruierte oder kommerziell vertriebene Instrumente zur automatischen Cuffdruckmessung und -begrenzung vorgestellt worden [21,29].Die Eigenbauten besitzen nicht das Zertifikat der "Communauté Européenne" (CE) und entsprechen nicht den Vorschriften des Medizinproduktegesetzes oder der Medizingeräteverord-nung. Somit sind sie aus rein rechtlichen Gründen heute nicht mehr zulässig.…”

“…Sonst resultiert je nach N 2 O-Anteil ein Anstieg oder ein Abfall des Cuffdrucks [20]. Es existieren zahlreiche weitere Ansätze,die jedoch bisher zu keiner befriedigenden Lösung des Problems geführt haben [18,21,23]. Nach Cobley et al führen bereits geringe Volumenänderungen des initialen Blocks zu relativ großen Änderungen des Ausgangscuffdrucks.…”