title: Comparison of Cobra perilaryngeal airway (CobraPLA™) with flexible laryngeal mask airway in terms of device stability and ventilation characteristics in pediatric ophthalmic surgery.
abstract: BACKGROUND
  Supraglottic airway devices play an important role in ophthalmic surgery. The flexible laryngeal mask airway (LMA™) is generally the preferred airway device. However, there are no studies comparing it with the Cobra perilaryngeal airway (CobraPLA™) in pediatric ophthalmic procedures.
  
  
  OBJECTIVE
  To analyze the intraoperative device stability and ability to maintain normocarbia of CobraPLA™ and compare it to that with flexible LMA™.
  
  
  METHODS
  Ninety children of American Society for Anesthesiologists physical status 1 and 2, aged 3-15 years scheduled for elective ophthalmic surgeries were randomly assigned to either the CobraPLA™ or the flexible LMA™ group. After placement of each airway device, oropharyngeal leak pressure (OLP) was noted. Adequate seal of the devices was confirmed at an inspired pressure of 15 cm H(2)O and pressure-controlled ventilation was initiated. Device displacement was diagnosed if there was a change in capnograph waveform, audible or palpable gas leak, change in expired tidal volume to <8 ml/kg, end-tidal carbon-dioxide persistently >6 kPa, or need to increase inspired pressure to >18 cm H(2)O to maintain normocarbia.
  
  
  RESULTS
  Demographic data, duration, and type of surgery in both the groups were similar. A higher incidence of intraoperative device displacement was noted with the CobraPLA™ in comparison to flexible LMA™ (P < 0.001). Incidence of displacement was higher in strabismus surgery (7/12). Insertion characteristics and ventilation parameters were comparable. The OLP was significantly higher in CobraPLA™ group (28 ± 6.8 cm H(2)O) compared to the flexible LMA™ group (19.9 ± 4.5 cm H(2)O) (P < 0.001). Higher surgeon dissatisfaction (65.9%) was seen in the CobraPLA™ group.
  
  
  CONCLUSIONS
  The high incidence of device displacement and surgeon dissatisfaction make CobraPLA™ a less favorable option than flexible LMA™ in ophthalmic surgery.
authors.affiliation: Department of Anaesthesiology and Intensive Care, Rajendra Prasad Institute of Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Rani A
authors.initials: RA
authors.lastname: Sunder
authors.forename: Renu
authors.initials: R
authors.lastname: Sinha
authors.forename: Anil
authors.initials: A
authors.lastname: Agarwal
authors.forename: Bala Chandran Sundara
authors.initials: BC
authors.lastname: Perumal
authors.forename: Sakthi Rajan
authors.initials: SR
authors.lastname: Paneerselvam