The LMA ® Protector TM in anaesthetised, non-paralysed patients: a multicentre prospective observational study

Abstract

We evaluated the LMA ® Protector TM in 280 ASA physical status 1–3 patients aged 18–75 years by assessing the ease of insertion, insertion time, oropharyngeal leak pressure, ease of gastric tube passage and complications. First-attempt and overall insertion success was 234/280 (84; 95%CI 79–88%) and 274/280 (98; 95–99%). Median (IQR [range]) insertion time was 17 (12–25 [5–44]) s, and manoeuvres to facilitate insertion were required in 56 (50–63)% of patients. Median oropharyngeal leak pressure was 31 (26–36 [14–40]) cmH 2 O. Multivariate analysis identified two risk factors for oropharyngeal leak pressure < 25 cmH 2 O: male sex (OR 2.44; 1.01–5.91, p = 0.048) and the insertion of a LMA size different to that recommended by weight (OR 1.98; 0.97–4.03, p = 0.06). Gastric tube insertion was possible in 256 out of 274 patients (93%). On fibreoptic view, vocal cords were visible in 86% of patients. During maintenance, 14 patients (5%) required airway manipulation. There were no episodes of regurgitation or aspiration. Blood staining on LMA removal was present in 70 out of 280 patients (25%). Use of the LMA Protector appears safe and is associated with a high success rate, provision of a highly effective seal and low rates of clinical complications. These attributes would suggest considerable potential for use during anaesthesia.