Laboratory and clinical comparisons of the Streamlined Liner of the Pharynx Airway (SLIPA) with the laryngeal mask airway

Abstract

The Streamlined Liner of the Pharynx Airway (SLIPA) is a new inexpensive disposable supraglottic airway designed to seal without the use of an inflatable cuff. It comprises a hollow blow-moulded soft plastic airway shaped to form a seal in the pharynx. Being hollow, liquid entrapment is possible and this may provide effective protection against aspiration. A model silicone rubber pharynx with an 'oesophageal' tube for injecting volumes of regurgitant liquid was designed to evaluate the SLIPA and the standard and ProSeal laryngeal mask airways during positive-pressure ventilation. A linear relationship between the volume 'regurgitated' and the volume 'aspirated' was found with the laryngeal mask airway and the ProSeal laryngeal mask airway with the drainage tube clamped. Both the ProSeal laryngeal mask airway with an open drainage tube and the SLIPA, but not the standard laryngeal mask airway, provided effective protection against 'aspiration' during positive-pressure ventilation using the model. In a clinical study, 120 patients were randomly allocated to receive controlled ventilation of the lungs via the standard laryngeal mask airway or the SLIPA. Both devices were equally easy to insert and satisfactory for airway management.