[Serialization] Experience of Xiaowu Xue Laryngeal Mask (5) Correct Insertion Method of Laryngeal Mask

Proper laryngeal mask placement techniques — To avoid the patient's coughing, gagging, laryngospasm, breath-holding, or exertion, adequate depth of anesthesia with intravenous (IV) anaesthetic or inhalation anaesthetic is usually obtained before SGA placement
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Successful placement of SGA in awake patients with adequate oropharyngeal topical anesthesia has also been reported [9]
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In general, SGA placement is less irritating than endotracheal intubation
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Several methods of placing the SGA have been reported, and we generally follow the LMA Classic placement instructions provided by the manufacturer before trying other methods
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The techniques are summarized as follows (figure): • Lubricate the LMA cuff with a water-based lubricant
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• The device is then held in the dominant hand with the index finger at the junction of the cuff and airway tube
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●Press the cuff up against the hard palate with the index finger, then move it smoothly back and down along the hard palate until resistance is encountered
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When the index finger is removed, immediately push down on the LMA with the non-dominant hand to prevent dislodgement
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●The cuff is then inflated to a target pressure of around 44mmHg or the minimum pressure required for an adequate seal [10]
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When properly inserted, the LMA covers the glottis and the epiglottis is located in the vent hole of the laryngeal mask
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The correct position of the LMA can be confirmed clinically by the following methods: It is easier to achieve positive pressure ventilation (PPV), and the required ventilation pressure is low.
The thorax is properly lifted with each breath.
The capnography is normal.
The peak pressure of 20mmHg When the LMA is properly placed, the inflation of the cuff may dislodge the catheter outward, and there may be a slight bulge in the neck
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However, some malpositions may not be clinically apparent and may not be recognized unless FIS is used
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Common causes of misplacement include sub-epiglottis or inversion of the LMA cuff, which may require reinsertion
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After insertion of the LMA, the cuff pressure can be checked with a dedicated pressure gauge unless the LMA being used has a built-in pressure gauge
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 Other SGAs are placed similarly to the LMA Classic, with the exception of the LMA Supreme (also known as a dual-chamber LMA), which incorporates a retaining plate, which allows it to be placed without inserting the index finger into the patient's mouth
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 An example of a perfect laryngeal mask implantation selection: suitable laryngeal mask model to check the air tightness of the laryngeal mask Shape: V-shaped hand shape, fully evacuated the mask body, synchronous pumping and pressing Depth: Raise the mandible (adult)/pinch the trapezius muscle (infant and young children) Manipulation: The two-man operation assistants stand in a good position and support the mandible during insertion.
Pay attention to the lips and protect the operator's index finger during the insertion.
Oral cavity, place it against the hard palate ③ Advance along the velopharyngeal curve, hold the index finger against it, and push it in place by rotating it counterclockwise 90° ④ Adequate deflation is the key The maximum size of the type of laryngeal mask ⑨ Confirm the cuff pressure < 60cmH2O ⑩ Check the parameters of the anesthesia machine, check the ventilation effect Fixed: the tape is crossed, the ventilation mask is not forced, the ventilation tube is not forced Single operation: open the airway with scissors, non-operating hands Support the pillow, or lift the jaw.
Link to the experience of the laryngeal mask in Xiaowu school (1) The status and history of the laryngeal mask in Xiaowu school.
The experience of laryngeal mask (3) those laryngeal masks in textbooks ~ the experience of Xiaowuxue laryngeal mask (4) model selection and indications, contraindications