Written and maintained by CASRAI Editorial Board
Last updated
General product information only, not medical advice. This page does not describe how to place or use any airway device, and it does not tell anyone which size to use on a patient. Always follow the manufacturer’s instructions for use and your own facility’s clinical protocols.
A laryngeal mask airway sizes chart lets a reader match a device size to the manufacturer’s weight guide. The chart below covers one product family, the Intersurgical i-gel, because its size names and weight guides are published in the manufacturer’s own information sheet. Sizes are specific to each product and brand, so a chart for one device cannot be applied to another.
What is a laryngeal mask airway?
A laryngeal mask airway is a supraglottic airway device: it sits above the vocal cords rather than passing through them, unlike an endotracheal tube. The i-gel is described by its manufacturer as a single-use, sterile supraglottic airway with a non-inflatable cuff made of a soft gel-like material, so no cuff inflation is required.
Laryngeal mask airway size chart (i-gel, by weight)
| Size | Manufacturer’s name | Weight guide |
|---|---|---|
| 1 | Neonate | 2-5 kg |
| 1.5 | Infant | 5-12 kg |
| 2 | Small paediatric | 10-25 kg |
| 2.5 | Large paediatric | 25-35 kg |
| 3 | Small adult | 30-60 kg |
| 4 | Medium adult | 50-90 kg |
| 5 | Large adult | 90+ kg |
Source: Intersurgical, i-gel Information Sheet, Issue 17 (06.24), code IS6.3, checked 30 October 2026. Check your product’s labelling and instructions for use before relying on any size figure.
How to read the chart
The manufacturer states that i-gel comes in four paediatric and three adult sizes, covering patients from 2 kg to 90+ kg. Each row pairs a size number with a name and a weight guide. Two things stand out when you read the rows together:
- The weight guides overlap. Size 3 (30-60 kg) and size 4 (50-90 kg) share 50-60 kg, and size 2 (10-25 kg) overlaps size 1.5 (5-12 kg) at 10-12 kg. The manufacturer labels these figures a weight guide.
- There is no cuff-volume column. Because the i-gel cuff is non-inflatable and the manufacturer states that no cuff inflation is required, a cuff-volume column does not apply to it.
How sizes are chosen: weight and anatomy
Manufacturer guidance for supraglottic airways is traditionally weight-based. A 2026 randomised study in the Indian Journal of Anaesthesia (Yadav et al.) looked at the ProSeal laryngeal mask, a different device, in 116 adults (ASA I-II). It noted that body weight alone does not reliably reflect individual differences in upper airway anatomy, and compared weight-based selection with selection by ultrasound-measured hyomental distance.
Weight-based selection chose size 3 in 25.9% and size 4 in 74.1% of patients; the hyomental-distance method chose size 3 in 60.3% and size 4 in 39.7% (P<0.001). First-attempt success was 93.1% versus 96.6% (P=0.67), not a significant difference. This is a single-centre study of one device and is not clinical guidance.
Common mix-ups
- Applying one brand’s chart to another. Size numbers, names and weight guides are product-specific. Use the chart and labelling for the exact device in hand.
- Looking for a cuff volume. It applies to inflatable-cuff designs, not to the non-inflatable i-gel cuff.
- Treating overlapping weights as an error. The manufacturer’s published table itself shows overlapping ranges.
Frequently asked questions
What is a laryngeal mask airway?
It is a supraglottic airway device that sits above the vocal cords for airway management. The i-gel is a single-use, sterile example with a non-inflatable cuff, per its manufacturer.
How many sizes does the i-gel come in?
Seven: 1, 1.5, 2, 2.5, 3, 4 and 5, from neonate (2-5 kg) to large adult (90+ kg) weight guides.
Can I use this chart for another brand?
No. Sizing is specific to each product; read that product’s labelling and instructions for use.
Related product categories are listed under emergency and trauma supplies. For related equipment, see the guides to the laryngoscope, capnography and the ambulatory surgery center supply checklist.
Sources
- Intersurgical. i-gel Information Sheet – Airway Management, Issue 17 (06.24), IS6.3. https://www.intersurgical.com/info/igel. Checked 30 October 2026.
- Yadav S, Rani R, Verma D, et al. Ultrasound-guided hyomental distance versus weight-based method for ProSeal LMA size selection: a randomised controlled study. Indian J Anaesth 2026. doi 10.4103/ija.ija_76_26 (PMC13626511). https://pmc.ncbi.nlm.nih.gov/articles/PMC13626511/. Checked 30 October 2026.
