Related Experiment Video
Updated: Apr 19, 2026

Laryngeal Mask Airway LMA Placement in a Neonatal Patient Simulator Using a Non-Inflatable Supraglottic Airway SGA
Published on: July 14, 2023
Optimal Size AMBU® Laryngeal Mask Airway Among Asian Adult Population
M Y Tang1, I P Tang2, C Y Wang3
1University Malaysia Sarawak, Faculty of Medicine and Health Sciences, Department of Surgery, Jalan Tun Ahmad Zaidi Adruce, 93150 Kuching, Malaysia. ingptang@yahoo.com.
Aim:
This was a randomized single blinded study to determine optimal size for Ambu®LMA (ALMA) among Malaysian adult population.
Methods:
One hundred and twenty six non-paralyzed anaesthetized adult patients were block randomized into size 3, 4 and 5 Ambu®LMA. Optimal size is defined primarily by oropharyngeal pressure (OLP). Pharyngeal injury and ease of insertion are also taken into consideration.
Results:
Mean OLP was significantly higher for Size 4 and 5 compared to size 3 (p<0.001) but similar between size 4 and 5. Number of insertion attempts and insertion time were similar between sizes. Size 5 required more manipulations during insertion (p<0.005) and had higher pharyngeal injury (p=0.001) compared to size 3 and 4.
Discussion:
We recommend size 4 ALMA as the optimal size for Malaysian adults in view of the higher OLP compared to size 3, yet less pharyngeal injury than size 5 in spontaneously breathing patients.
Related Concept Videos
Cardiopulmonary Resuscitation II: ACLS Airway Management
Cardiopulmonary Resuscitation V: Advanced Airway Management Techniques
Oxygen Delivering System I: Nasal Cannula and Face Mask
Nasal Cannula
A nasal cannula is a lightweight tube split at one end into two prongs and placed in the nostrils. It is typically used to deliver low to medium levels of oxygen.
Suggested flow rate: The suggested flow rate for a nasal cannula typically ranges between 1 and 6 L/min.
Oxygen percentage setting:...
Assessment of Airway, Skin Color, and Use of Accessory Muscles
Introduction
The initial evaluation of a patient's respiratory system...
Suctioning the Oropharyngeal Airway
After assembling the equipment, the nurse should practice hand hygiene and don appropriate PPE according to infection control guidelines to avoid the...
Oxygen Delivering System II: Venturi Mask and Transtracheal Oxygen
Venturi Mask
The Venturi mask, named after the Venturi effect, is designed to deliver precise oxygen concentrations. It consists of a large tube with an oxygen inlet that narrows down, causing a pressure drop that pulls air in through adjustable side ports. The mask is a lightweight,...

