Comparison of the i-gel with the cuffed tracheal tube during pressure-controlled ventilation.
BACKGROUND
The i-gel (Intersurgical Ltd) is a novel device that differs from other supraglottic airway devices in that it has a softer and a non-inflatable cuff. Our study was designed to assess whether the i-gel is suitable to provide pressure-controlled ventilation (PCV) during anaesthesia by measuring the gas leaks and comparing these values with that of the tracheal tube.


METHODS
Twenty-five patients, ASA I-II, were recruited to the study. Patients received a standard anaesthetic technique followed by an initial placement of the i-gel. The lungs were then ventilated at three different pressures (15, 20, 25 cm H(2)O) using PCV. The difference between the inspired and expired tidal volumes was used to calculate the leak volume. The leak fraction was defined as the leak volume divided by the inspired tidal volume. Following these observations, the i-gel was removed and replaced with the conventional tracheal tube and the recordings repeated.


RESULTS
There was no significant difference between the leak fractions of the i-gel and the tracheal tube at 15 and 20 cm H(2)O PCV. At 25 cm H(2)O, the median difference in leak fraction was 0.02 (P=0.014) and the median difference in leak volume was 26.5 ml (P=0.006). There was no evidence of gastric insufflations with any of the pressures used during PCV.


CONCLUSIONS
We suggest that the i-gel can be used as a reasonable alternative to tracheal tube during PCV with moderate airway pressures.
Uppal
V
V
Section of Anaesthesia, Pain and Critical Care, Faculty of Medicine, University of Glasgow, Glasgow, UK. drvishal76@rediffmail.com
Fletcher
G
G
Kinsella
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D000399:Air Pressure; D000768:Anesthesia, General / Q000379:methods; D004867:Equipment Design; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D017214:Laryngeal Masks / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000379:methods*; D013990:Tidal Volume; D055815:Young Adult