British Journal of Anaesthesia, Vol 80, Issue 4 470-474, Copyright © 1998 by The Board of Management and Trustees of the British Journal of Anaesthesia
T. Asai, T. K. Howell, K. Koga and S. Morris
We have compared size 3 and size 4 laryngeal masks in 30 females and size 4
and size 5 in 30 males for success rate of insertion, incidence of airleak
and pressure exerted on the pharynx. First, the ex vivo volume-pressure
relationship of the mask was obtained. Second, after insertion of a mask,
the cuff was inflated with the recommended maximum volume of air and
intracuff pressure measured. Third, the incidence of airleak during a
steady airway pressure of 18 cm H2O was noted. Fourth, the cuff was
deflated until it just prevented airleak, and cuff pressure was measured.
The mask was removed, the other size was inserted and the same procedure
repeated. At the end of operation, final in vivo and ex vivo pressures were
measured. The pressure exerted on the pharynx was calculated as the
difference between ex vivo and in vivo intracuff pressures. It was always
possible to insert both sizes in both sexes. In females, airleak occurred
in 15 patients with the size 3 and in five patients with the size 4
(difference: P = 0.005) and in males, 21 patients with the size 4 and in
four patients with the size 5 (P < 0.001). Removal of air to the minimum
effective volume significantly decreased intracuff pressure and pressure on
the pharynx; on removal of the mask, pressures were similar to, or lower
than, initial pressures. Therefore, a larger mask (size 4 in females and
size 5 in males) provided a better seal than a smaller size without
producing higher pressures on the pharynx.
CLINICAL INVESTIGATIONS
Appropriate size and inflation of the laryngeal mask airway
Department of Anaesthesiology, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi City, Osaka 570, Japan; Department of Anaesthetics and Intensive Care Medicine, University Hospital of Wales, Heath Park, Cardiff CF4 4XN; Llandough Hospital NHS Trust, Penlan Road, Penarth, South Glamorgan CF64 2XX
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  S. Kihara and J. Brimacombe Sex-Based ProSealTM Laryngeal Mask Airway Size Selection: A Randomized Crossover Study of Anesthetized, Paralyzed Male and Female Adult Patients Anesth. Analg., July 1, 2003; 97(1): 280 - 284. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. A. Gaitini, S. J. Vaida, M. Somri, V. Kaplan, B. Yanovski, R. Markovits, and C. A. Hagberg An Evaluation of the Laryngeal Tube(R) During General Anesthesia Using Mechanical Ventilation Anesth. Analg., June 1, 2003; 96(6): 1750 - 1755. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Kihara, Y. Yaguchi, J. Brimacombe, S. Watanabe, N. Taguchi, and N. Hosoya Intubating Laryngeal Mask Airway Size Selection: A Randomized Triple Crossover Study in Paralyzed, Anesthetized Male and Female Adult Patients Anesth. Analg., April 1, 2002; 94(4): 1023 - 1027. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Asai, K. Murao, and K. Shingu Cricoid pressure applied after placement of laryngeal mask impedes subsequent fibreoptic tracheal intubation through mask{dagger} Br. J. Anaesth., August 1, 2000; 85(2): 256 - 261. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Keller and J. Brimacombe Mucosal pressure and oropharyngeal leak pressure with the ProSeal versus laryngeal mask airway in anaesthetized paralysed patients Br. J. Anaesth., July 1, 2000; 85(2): 262 - 266. [Abstract] [Full Text] [PDF]
|
|