2. -HOW TO MAINTAIN THE PATIENTS
AIRWAY
DURING GENERAL ANESTHESIA
USING
DIFFERENT TOOLS AND METHODS
3. -Airway devices that lie outside the trachea and attempt to provide a leak – Free seal
for spontaneous ventilation and an adequate seal for positive pressure ventilation
-SUPRAGLOTTIC
(OR EXTRAGLOTTIC)
AIRWAY DEVICES
ADVANTAGES
--1-The ability to be placed without direct visualization of the Larynx
--2-Increased speed and ease of placement when compared with tracheal intubation
--3-Increased cardiovascular stability on insertion and emergence.
--4-During emergence, improved oxygen saturation and lower frequency of coughing
--5-Minimal rise in intraocular pressure on insertion
--6-When the device is properly placed, It can act as a conduit for oral tracheal intubation
due to the anatomical alignment of its aperture with the glottic opening.
--7-In the “Cant Intubate, Cant Ventilate” scenario, the decision to use such devices should
be made early to gain time while attempts are made to secure a definite airway
--8-These devices are increasingly used in a variety of settings, including routine anesthesia
emergency airway management and as an aid to intubation
4. --9-Such devices normally provide little or no protection against aspiration
of refluxed gastric contents, and are therefore contraindicated in patients
with full stomachs or prone to reflux However second - generation devices
offer many improvements such as high cuff seal second seal, gastric access
and drain tube. These allow for rapid drainage of gastric fluids or secretions
and reduce the risk of gastric gas insufflation during ventilation
--10-Extraglottic airways would normally elicit airway reflexes such as the gag
reflex, and therefore require depression of pharyngeal reflexes by General
or Topical Anesthesia
-SUPRAGLOTTIC
(OR EXTRAGLOTTIC)
AIRWAY DEVICES contd.
5. It was developed by Archie Brain (1988-A British)
-This is very useful Device it is frequently used as an alternative to either the
face-Mask or tracheal tube during Anesthesia
DESIGN
--1-It is reusable made of silicone rubber (i.e Latex free) and autoclavable. It consists
of a wide-bore tube whose proximal end is connected to a breathing circuit with
a slandered 15 – mm connector and whose distal end is attached to an elliptical
cuff which is inflated by a pilot tube
--2-The cuff resembles a small face Mask to form an air tight seal around the
posterior perimeter of the larynx
--3-The original design (Classic LMA) had two slits or bars at the junction between the
tube and the cuff to prevent the Epiglottis from obstructing the lumen of the
Laryngeal Mask
-LARYNGEAL MASK AIRWAY (LMA)
7. --a-Instead of the face Mask in minor procedures, thus no need for the
Anesthesiologist’s hand to support the Mask
--b-Instead of the endotracheal tube (for spontaneous ventilation) with
the following advantages
--1-Pressor response of intubation is avoided, therefore, it is preferred
in patients with Ischemic heart disease or Hypertension
--2-Smooth induction and recovery are allowed
This decreases the risk of increased intraocular pressure, so it is
used in intra – ocular procedures
--3-LMA is less invasive then intubation. It is preferred specially in
out – patient Anesthesia
--4-Diagnostic Fiberoptic Laryngoscopy and Bronchoscopy can be done
via the Laryngeal Mask allowing supplying patients with Oxygen
N.B:-It can be used for mechanical ventilation with keeping airway
pressure between 15 to 20 cm H2O to avoid gastric insufflation and
oropharyngeal leak
-INDICATIONS
8. --1-It is used as an airway in case of “Cannot intubate, Cannot ventilate” because of its ease of use
(Its success rate upto 99%)
--2-In 1996 it entered the American Society of Anesthesiologists difficult airway algorithm, both as
a ventilatory device (airway) and a conduit for endotracheal intubation
--3-Cardiopulmonary resuscitation
--4-It is used as a conduit for an intubating stylet, bougie, ventilating jet stylet, flexible fiberoptic
Bronchoscope
--5-It is used in patients with cervical spine injury because it can be applied in neutral position
----In Pulmonary medicine and Thoracic surgery: LMA is used.
--6-To place tracheal and bronchial stents
--7-To perform diagnostic fiberoptic Laryngoscopy via LMA.
----Anesthesia outside the operating room.
Such as radiation therapy, diagnostic and interventional radiology, endoscopy, or cardioversion.
--N.B:-It is recommended for operations 2 to 3 hours. If Prolonged surgery is expected, Intra – cuff
pressure should be monitored and should not exceed 60 cm H2O to avoid pressure injury of
pharyngeal mucosa
-PROCEDURE
IN DIFFICULT INTUBATION
9. --1-Pharyngeal (Glottis or Subglottic) pathology as abscess,
surgery spasm, massive edema, Tumor, Hematoma, or
any other cause of obstruction
--2-Full stomach or causes of delayed Gastric emptying
e.g Obstetrics Hiatus Hernia or Oesophagus reflux
--3-High airway resistance e.g Bronchospasm
--4-Low pulmonary compliance e.g Obesity
N.B:-Both 3 and 4 require peak inspiratory pressure > 20
cm H2O which could increase gastric distension
--5-One lung ventilation
-CONTRAINDICATIONS
10. --1-Inflation of the stomach especially when – peak inspiratory pressure
exceeds 20 cm H2O or the esophagus lies within the Rim of the cuff,
both increases the risk of regurgitation
a-The incidence of regurgitation with LMA is 2 in 10,000 cases
b-The incidence of regurgitation with E.T.T is 1.7 in 10,000 cases
i.e nearly the same
--2-Sore throat would be present in 4 to 12% of patients
--3-Coughing and Laryngospasm (as oropharyngeal airways)
--4-Risk of airway obstruction in 25 to 50% of pediatrics and 10% of
adults due to
a- Down – folding of epiglottis or
b-Distal end of the cuff
--5-Trauma to the airway
-COMPLICATIONS
11. EQUIPMENT’S
--1-Appropriate size LMA
--2-Syringe with appropriate volume
for LMA cuff inflation
--3-Water soluble lubricant
--4-Ventilation equipment
--5-Stethoscope
--6-Tape or other device (s) to secure LMA
--7-Capnography
-LMA INSERTION
12. --1-Select the size of the LMA which is suitable for the patient
RECOMMENDED SIZE GUIDELINES
-LMA INSERTION TECHNIQUE
--SIZE---1 UNDER 5 KG
--SIZE---1.5 5 TO 10 KG
--SIZE---2 10 TO 20 KG
--SIZE---2.5 20 TO 30 KG
--SIZE---3 30 KG TO SMALL ADULT
--SIZE---4 ADULT
--SIZE---5 LARGE ADULT
--2-Inspect the LMA cuff for tears or other abnormalities
--3-Slowly deflate the cuff to form a smooth flat wedge
shape which will pass easily around the back of
the tongue and behind the Epiglottis
--4-Use the water soluble lubricant to lubricate the back of LMA
--5-Extend the Head and Flex the neck (SNIFFING POSITION)
13. --6-Grasp the LMA by the tube, holding it like a pen as near as possible to the mask end
--7-Place the Tip of the LMA against the inner surface of the patient’s upper teeth
--8-Under direct vision, Press the Mask Tip upwards against the hard palate to flatten it
out using the index finger, keep pressing upwards as you advance the Mask into the
pharynx to ensure the Tip remains flattened and avoids the tongue
--9-Keep the neck Flexed and Head extended (SNIFFING POSITION) the longitudinal black
line should always be pointing directly Cephalad (i.e Facing the patient’s upper Lip)
-10-Press the Mask into the posterior pharyngeal wall using the index finger and continue
pushing with your index finger and guide the Mask downwards into position
-11-Grasp the tube firmly with the other hand and then withdraw your index finger from
the pharynx and press gently downwards with your other hand to ensure the Mask is
fully inserted
-LMA INSERTION TECHNIQUE contd.
15. -12-Inflate the Mask with recommended volume of air
-LMA INSERTION TECHNIQUE contd.
--SIZE 1- 4 ML
--SIZE 1.5- 7 ML
--SIZE 2 10 ML
--SIZE 2.5- 14 ML
--SIZE 3- 20 ML
--SIZE 4- 30 ML
--SIZE 5- 40 ML
-Do not over inflate the LMA
- Do not touch the LMA tube while it being inflated unless the position is obviously
unstable
-Normally the Mask should be allowed to rise up slightly out of the Hypopharynx as
it is inflated to find its correct position
--13-Connect the LMA to a Bag – Valve – Mask device or low pressure ventilator
--Ventilate the patient while confirming equal breath sounds over both Lungs in all fields and the
absence of ventilatory sounds over the Epigastrium
-14-Insert a bite – block or a Roll of gauze to prevent occlusion of the tube
-15-Now the LMA can be secured utilizing the same technique as those employed in the securing
of an endotracheal tube
16. --N.B:- Obstruction after insertion is usually due to – a downfolded
Epiglottis or distal cuff or transient Laryngospasm
-LMA INSERTION COMPLICATIONS
17. -1-It should be either when the patient is deeply anesthetized or after
awakening and regaining of airway reflexes. Pharyngeal suction of
secretions is usually not necessary before removing LMA.
If suctioning is to be performed, it is important to ensure that an
adequate level of anesthesia is present to avoid unnecessary
airway manipulation.
-2-The cuff of the LMA may be either deflated before removal or left fully
inflated to scoop out the secretions above the mask as it is withdrawn.
-3- At the end, the reusable LMA should be deflated evenly by a special
deflator to avoid attaining an abnormal shape during the re-sterilization
and reuse
-REMOVAL OF LMA
18. --1- Classic (standard) LMA.
--2- Flexible LMA: It is armored, wire-reinforced LMA.
--3- Disposable (unique) LMA
--4- LMA-Fastrach (Intubating LMA) (ILMA):
--The two bars at the aperture of the regular LMA have been replaced
by a single, movable epiglottic elevating bar that allows a smooth and
unobstructed passage of an endotracheal tube as it emerges from the
rigid metal shaft of the LMA-Fastrach. The shaft is shorter in length,
thus eliminating the need for a longer endotracheal tube.
--5-It has three sizes: -
a-Size 3 for a small adult or a large child.
b- Size 4 for a normal adult.
c-Size 5 for a large adult.
The three sizes will accept a tube of up to 8 mm internal diameter.
-TYPES OF LMA
21. -- 5- Gastric (Proseal) LMA (PLMA)
--It has a modified posterior cuff that extends onto the back of the mask to
improve the laryngeal seal therefore, allowing high positive pressure application.
--There is also a 2nd channel for gastric tube placement or passage of regurgitated
fluid. This protects airway against aspiration .
--It is reusable but a disposable single use device is also available
--Gastric (Proseal) LMA (PLMA): is available in sizes 2, 3, 4, and 5.
--6- LMA C-Trach:
--It is a modified ILMA. It has the same anatomically curved stainless steel tube
and is available in 3 mask sizes (3, 4, and 5).
--The epiglottic elevating bar has been modified to allow visualization of the
larynx by means of fiberoptic bundles located within the bowl of the mask.
--A lightweight viewer is magnetically attached after the device has been inserted
-TYPES OF LMA contd.
23. -7- I GEL AIRWAY
-TYPES OF LMA contd.
--The i-gel airway is a single-use extra glottic airway that uses an anatomically designed
mask to fit the peri laryngeal and hypopharyngeal structures without the use of an
inflatable cuff
--The soft, gel-like plastic from which the i-gel is manufactured is intended to mould into
place without the use of an inflatable cuff.
--It also incorporates a second drain tube.
--It is available in adult, paediatric and neonatal sizes (1, 1.5, 2, 2.5, 3, 4, and 5).
24. --A single-use version, is available which combines the best features of previous LMA versions,
and contains an elliptical and anatomically shaped curve, which facilitates insertion success
and provides a double seal.
--A first seal is important for adequacy of gas exchange, better known as the oropharyngeal seal.
--8- SUPREME LMA
-TYPES OF LMA contd.