A comparison of the cuffed oropharyngeal airway (COPA) with the laryngeal mask airway (LMA) during manually controlled positive pressure ventilation

M Heringlake, V Doerges, H Ocker, P Schmucker
Journal of Clinical Anesthesia 1999, 11 (7): 590-5

STUDY OBJECTIVE: To examine the cuffed oropharyngeal airway (COPA) during positive pressure ventilation (PPV) and to compare its reliability and efficacy with the laryngeal mask airway (LMA).

DESIGN: Prospective, randomized, controlled trial.

SETTING: University Hospital.

PATIENTS: 60 adult ASA physical status I and II patients scheduled for urologic surgery.

INTERVENTIONS: Patients were randomly assigned to be ventilated with a COPA (n = 33) or a LMA (n = 27) during a standardized anesthetic procedure. Following preoxygenation and induction with alfentanil and propofol, the respective airways were inserted. Patients were ventilated manually with the reservoir bag of the anesthesia respirator. Inspiratory airway pressure was limited to 20 cm H2O, and the target tidal volume was 7 ml/kg. Respiratory rate was adjusted to achieve an end-tidal pressure of carbon dioxide of 35 mmHg. Anesthesia was maintained with propofol, nitrous oxide in oxygen, and alfentanil, as appropriate.

MEASUREMENTS AND MAIN RESULTS: We evaluated ease of insertion (nominal scale: easy, moderate, difficult, or impossible) and recorded the number of maneuvers performed during insertion until an airtight seal of the airway was achieved. Reliability for "hands free" ventilation--defined as ventilation without the need to further augment the position of the airway device manually--was determined (nominal scale: adequate ventilation, adequate ventilation with manual assistance, and inadequate ventilation leading to airway change). Ventilation and oxygenation parameters were derived from the anesthesia respirator and a capillary blood gas sample, respectively. The incidence of laryngopharyngeal discomfort and the amount of salivation were assessed by nominal scales. The COPA was easier to insert than the LMA (p < 0.001), but more positional maneuvers (p < 0.001) were necessary with this device. "Hands free" ventilation was achieved less often with the COPA (p < 0.02). Ventilation and oxygenation were comparable with both devices. The COPA was associated with less salivation (p < 0.01) and laryngopharyngeal discomfort (p < 0.05) than the LMA.

CONCLUSION: Although effective ventilation can be accomplished with both devices, the LMA is more reliable for "hands free" ventilation than the COPA. The lower incidence of laryngopharyngeal discomfort and salivation with the COPA may be beneficial for patients at risk for developing laryngospasm.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Available on the App Store

Available on the Play Store
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"