Background and objective: To compare the application of the cuffed oropharyngeal airway and the laryngeal mask airway on anaesthetized adult patients undergoing minor outpatient surgery.

Methods: One hundred patients received intravenous fentanyl, propofol and N2O for the induction and maintenance of anaesthesia. The patients were randomly divided into two groups: a cuffed oropharyngeal airway group (n = 50) and a laryngeal mask airway group (n = 50). After insertion of the device, fibreoptic laryngoscopy was attempted and the degree of success scored. We then compared the first application success rate of both procedures while judging airway intervention requirement, fibreoptic scores, adverse airway events and haemodynamic tolerance.

Results: Both devices had an almost similar first-time placement rate (cuffed oropharyngeal airway 84% versus laryngeal mask airway 96%). The cuffed oropharyngeal airway required a higher number of airway interventions (P < 0.001). The laryngeal mask airway had a significantly better fibreoptic view compared with the cuffed oropharyngeal airway (P < 0.001). However, the number of adverse airway events was lower in the cuffed oropharyngeal airway group; there were no significant differences in adverse events and haemodynamic variables between the said two groups.

Conclusions: The results suggest that the cuffed oropharyngeal airway was an effective alternative airway in spontaneously breathing patients during short procedures.

The cuffed oropharyngeal airway is a modified Guedel airway and is recommended for anaesthesia in spontaneously breathing patients. To our knowledge this is the first report of transient unilateral lingual nerve palsy after the use of a cuffed oropharyngeal airway to maintain anaesthesia during arthroscopy of an ankle. The aetiology of lingual nerve damage is multi-factorial. The possible mechanisms involved include anterior displacement of the mandible during insertion of the cuffed oropharyngeal airway (as in the jaw hrust manoeuvre), compression of the nerve against the mandible, or stretching of the nerve over the hyoglossus by the cuff of the cuffed oropharyngeal airway. We recommend gentle airway manipulation with the use of the cuffed oropharyngeal airway, avoidance of excessive cuff inflation and early recognition of such a complication if it occurs.

To evaluate arterial (PaCO2), end-tidal (PETCO2) and carbon dioxide tension difference during mechanical ventilation with extratracheal airways, 60 patients ASA physical status I-II, receiving general anaesthesia for minor extra-abdominal procedures were randomly allocated to receive either a cuffed oropharyngeal airway (group COPA, n=30) or a laryngeal mask (group LMA, n=30). The lungs were mechanically ventilated by IPPV using a 60% nitrous oxide and 1–1.5% isoflurane in oxygen mixture (VT8 mL kg−1; RR=12 b min−1; I/E=1/2). After PETCO2 had been stable for at least 10 min after airway placement, haemodynamic variables and PETCO2 were recorded and an arterial blood sample was obtained for measurement of PaCO2. No differences in anthropometric parameters, smoking habit, haemodynamic variables and incidence of untoward events were observed between the two groups. Airway manipulation, to maintain adequate ventilation, was required in only nine patients in the cuffed oropharyngeal airway group (30%)(P < 0.0005); however,in no case was it necessary to remove the designated extratracheal airway due to unsuccessful mechanical ventilation. The mean difference between arterial and end-tidal carbon dioxide partial pressure was 0.4±0.3 KPa in the laryngeal mask group (95% confidence intervals: 0.3–0.5 KPa) and 0.3±0.26 KPa in the cuffed oropharyngeal airway group (95% confidence intervals: 0.24–0.4 KPa) (P =NS). We conclude that in healthy adults who are mechanically ventilated via the cuffed oropharyngeal airway, the end-tidal carbon dioxide determination is as accurate an indicator of PaCO2 as that measured via the laryngeal mask, allowing capnometry to be reliably used to evaluate the adequacy of ventilation.