Supraglottic Airway Devices

Dr. Tarun YadavDr. Vijay Chandak

Anatomy of Upper airway

LMA

• Dr. Archie Brain developed LMA in 1982 as a modification of Goldman dental mask.

• Standard of airway management , filling the niche between facemask and tracheal tubes.

• They sit outside the trachea and provide a handsfree means of gas tight airway.

• The first Supraglottic airway device was LMA-Classic(1989)

Indications Contraindications

Alternative Airway during GA Risk of aspiration

Essential part of difficult airway trolley Local pathology in pharynx , larynx or upper airway.

Cardiopulmonary resuscitaion : to secure airway

Trismus, facial or upper airway trauma

Relative indication in professional singers:To avoid trauma to vocal cords

Morbid obese, > 14 week pregnant, prior opiods medication, delayed gastric empting

Reduced lung compliance/increase work of breathing

LMA Classic

Mask Size Patient size /Body Weight Maximum CuffInflation Volume (Air)

1 Neonates/Infants up to 5 kg Up to 4 mL

1.5 Infants 5–10 kg Up to 7 mL

2 Infants/Children 10–20 kg Up to 10 mL

2.5 Children 20–30 kg Up to 14 mL

3 Children 30–50 kg Up to 20 mL

4 Adults 50–70 kg Up to 30 mL

5 Adults 70–100 kg Up to 40 mL

6 Large Adults over 100 kg Up to 50 mL

Preparation Prior to Insertion

• Examine surface for cuts, tears, or scratches.• Examine 15 mm connector.• Deflate pilot balloon untill cuff walls tightly flattened.

Ensure the remain flattened.• Over inflate: look for leak.• Deflate against flat surface: ensure spoon shape.• Lubricate post surface with water soluble lubricant.

Avoid Lignocane jelly for lubrication

Technique of LMA insertion

• Position: Neck flexed and head extended.• Use non-inserting hand to stabilize occiput.• Jaw should be pulled down by assistant.• LMA tube be grasped like a pen with index finger

pressing the point where tube joins mask.• Aperture facing forward, the tip pressed upwards

against the hard palate.• Middle finger may be used to push lower jaw

downward.

• Mask is advanced into pharynx to ensure that tip remains flattened and avoids the tounge

• Neck is kept flexed and head extended.

• By withdrawing the other fingers and with a slight pronation of the forearm, it is usually possible to push the mask fully into position in one fluid movement

• The laryngeal mask is grasped with the other hand and the index finger withdrawn.

• The hand that is holding the tube presses gently downward until resistance is encountered.

Part of LMA Position

Distal tip of silicone cuff

Upper esophageal sphinter

Sides of the cuff Pyriform fossa

Upper part of the cuff

Tounge base

Seal Pressure LMA

20 cm H2O Classic, Unique, Flexible

30 cm H2O ProSeal

Causes of LMA malposition

• Placement during inadequate depth and/ or suppression of airway reflexes(pharyngeal muscle, laryngeal spasm)

• Inappropriate size selection• Small mouth , large tongue, tonsils• Post. Larynx : it blocks the placement of the

tip into hypopharynx.

Intubating LMA(LMA Fastrach)

Body weight ILMA size Air volume

30-50kg 3 20ml

50-70kg 4 30ml

70-100kg 5 40ml

Technique

• ILMA insertion• Position: Neutral• Hold rigid handle parallel to patient’s chest.• Glide the mask along the palate till the straight

part of the rigid tube is parallel to the chin.• Thereafter rotate the rigid handle directing

towards patient’s nose till it can not be advanced.• Inflate the cuff.

Technique

• Fastrach endotracheal intubation(FETT)• FETT is straight reinforced cuffed ETT with a transverse black

line and 15 cm mark of it coincides with the epiglottic elevating bar.

• Introduce FETT with black line faceing rigid handle till 15 cm mark.

• Now grip ILMA handle firmly and lift it forward by few mms without levering.

• Advance the tube using clinical judgment.• Inflate the cuff and check for tracheal intubation.

• After confirmation of tracheal intubation deflate the ILMA cuff.• With the stabilizer rod measure the distance bw proximal end of FETT

and patients incisors.• Remove FETT connector• Gently displace the ILMA along the pharyngeal curvature till the FETT

machine end tip at the level of universal connector of ILMA.• Now insert the stabilizing rod in the FETT to keep it in place.• Remove the ILMA gently over the stabilizing rod until it is clear of the

oral cavity.• Stablize the FETT to prevent accidental extubation.• Remove ILMA and the stabilizing rod.• Reconnect FETT connector and the breathing circuit and • confirm position again

Chandy’s maneuver

• They increases the seal pressure and aligns the axes of trachea and FETT.

• First step : Rotating ILMA in coronal & sagittal plane in an attempt to find find least resistant ventilation position.

• Second step : is to grasp the handle and use it to draw LMA forward 2-5 mm in a lifting action without levering teeth.

LMA ProSeal

Components LMA ProSeal

Insertion Technique

• Cuff deflated into a wedge shape.• Position: Sniffing position• Tip of the metal introducer is inserted into the

strap, airway and drain tube folded into it.• Adequate lubrication• The tip is pressed against the hard palate and

maneuvered to spread the lube around hard palate.

• Cuff is slid inward ,keeping pressure against the palate.

• As LMA proseal is inserted , introducer is kept close to chin.

• Introducer is swung inward in a smooth circular motion.

• Jaw should be pulled downward by assistant untill the cuff has passed the teeth.

• Jaw should not be left widely open.

• LMA ProSeal is advanced until resistance is felt.• Use non dominant hand to stablize the airway

tube as introducer is removed by following the curvature backward out of the mouth.

• Bite block should be at teeth.• Other methods: Digital method , Guided

method, Drain tube guided insertion

Advantages over LMA Classic• A softer silicone cuff reducing the likelihood of throat irritation and stimulation.

• 50% higher seal pressure – up to 30 cm H2O providing a tighter seal against the glottic opening with no increase in mucosal pressure– Provides more airway security– Enables use of PPV in those cases where it may be required – transient or extended, planned or unplanned

• A built-in drain tube designed to channel fluid away from the airway and permit gastric access for patients with GERD or during extended cases where endotracheal intubation is not required.

• Ability to realize the benefits of spontaneous ventilation more often• Optional insertion tool

LMA Supreme

LMA Unique

• Disposable LMA(DLMA).• Dimentions are identical to

standard LMA• Tube is stiffer cuff is less

compliant.• Better choice for out-of-hospital

or ward use where sterilization is difficult.

• Re-usable version is LMA Classic Excel.

LMA Flexiable

• Flexible wire reinforced airway tube.

• Length of airway tube is longer and diameter is smaller as compared to Classic LMA.

• Length and the flexibility makes it easier to move away from surgical area.

• Suitable for head and neck surgeries.

• Available both in adult and pediatric sizes.

LMA Ctrach

• Similar to ILMA in construction.• Two built in fiberoptic channels

- one to convey light from- another to convey image to viewer.- they emerge under epiglottic elevating

bars which lift the epiglottis as tube passes.

• Fiberoptic system is sealed and it can be autoclaved.

• Monitor is attached via a Magnetic latch connector.

I Gel