Laryngeal mask anesthesia is a general anesthetic that dispenses with endotracheal intubation and instead uses a laryngeal mask or laryngeal mask. Unlike a tube, which is often used to secure the airway during anesthesia, the so-called laryngeal mask is not inserted behind the vocal cords in the trachea, but remains in the throat before the larynx and is there inflated and secures the ventilation.
Basically, the laryngeal mask offers in most cases an alternative to classic endotracheal intubation to ensure ventilation during general anesthesia. However, there are also a number of contraindications that prohibit the use of the laryngeal mask. In all operations on the face, mouth and ear, nose and throat area, airway protection must be provided by endotracheal intubation, as a laryngeal mask may easily slip during movement and traction in the pharynx, as a result of its proximity to the surgical site, thus jeopardizing ventilation.
Even in patients who are not sober or pregnant, the laryngeal mask can not be used. In this group of patients there is always the risk of reflux of gastric contents into the esophagus and thus the risk of carry-over into the trachea. Since the laryngeal mask, in contrast to the tube, does not seal the trachea securely, it is clearly contraindicated here. For the same reason, there is also the indication for endotracheal intubation in patients suffering from heartburn or frequent regurgitation. Even for complex operations over several hours, the laryngeal mask is not suitable, here the tube also provides more security for the complication-free ventilation. For short surgeries in patients without pre-existing diseases of the stomach or the pharynx, the laryngeal mask is a gentle and safe alternative to endotracheal intubation.
Laryngeal ventilation provides many benefits during anesthesia. On the one hand, the mask is easier to use compared to the tube, moreover one does not need any further aids for inserting the mask, as in the case of the tube, the laryngoscope. This always brings with it the risk of injury to the surrounding tissue. Also, during anesthesia with a larynx mask, it is often possible to dispense with a muscle-relaxing medication and generally less anesthetic is used. This greatly shortens the wake-up period after surgery and is often described by patients as a gentle wake-up.
Another advantage of the laryngeal mask during the recovery phase after anesthesia is the lower irritation of the airways. Patients are less likely to wake up when they wake up and start to breathe spontaneously more relaxed. Many patients also find the laryngeal mask to be more comfortable than a tube because the vocal folds do not have to be passed and therefore no irritation can occur here. Sore throat therefore occurs less frequently after laryngeal mask anesthesia and hoarseness almost never.
The biggest problem with laryngeal mask anesthesia is that it is not a safe airway for laryngeal mask ventilation. This means that the mask can easily slip despite optimal storage and blocking of the cuff and endangers the oxygen supply. In particular, in operations in which the patient must be moved or relocated during the operation, there is a risk of slipping. Although the mask can be corrected in most cases by a simple measure, but this must be done during the operation under difficult conditions and is in rare cases no longer possible.
If this happens, emergency endotracheal intubation is required, which is associated with increased risk under severe conditions. Also, the laryngeal mask offers no protection against aspiration. If, after all, the gastric contents or gastric acid flow back into the neck area, it can pass through the laryngeal mask and enter the lungs via the trachea. This can lead to life-threatening pneumonia and damage.
Compared to endotracheal intubation, narcosis with a laryngeal mask is associated with some risks. Since the laryngeal mask is located behind the vocal folds due to its position in front of the larynx and not in the trachea, there is always the risk of slipping. Often, there is only a slight change in the situation, which only creates a leak in the oxygen supply. However, minimal correction to the mask usually makes it easy to close this leak again. However, if the mask is completely displaced or, in the worst case, the mask is withdrawn, an emergency intubation via the endotracheal tube is usually necessary.
The movement of the mask can lead to severe injury and swelling in the pharynx, which can ultimately lead to life-threatening airflow. Another serious complication of laryngeal mask anesthesia is aspiration. If gastric acid refluxes back into the esophagus, it can flow past the laryngeal mask and into the trachea and then into the lungs. In the lungs, gastric acid can cause serious damage and life-threatening pneumonia.
The risks and complications result in contraindications to the use of laryngeal masks. In all operations in which a rearrangement or the frequent movement of the patient is foreseeable, should be dispensed with a laryngeal mask. Here the endotracheal intubation is standard and takes place to secure the ventilation. Also, operations that take a long time or where you are working with strong pressure changes in the body, for example, in a Laperoskopie (abdominal wall) represent contraindications for the laryngeal mask.
In addition to the circumstances of the operation, patients may also give rise to a contraindication of a laryngeal mask. Due to the risk of aspiration, laryngeal masks should not be used in patients with known reflux disease or a tendency to frequent regurgitation. Also illnesses and infections in the area of the throat and the larynx forbid a Larynxmaske. Another contraindication for the use of laryngeal masks is an existing pregnancy or severe obesity. There is also a risk of aspiration here, as the high body weight in a lying position exerts strong pressure on the stomach, possibly producing a backflow of gastric acid into the esophagus.
Although the laryngeal mask is much gentler compared to the tube, in some cases it still causes sore throat after surgery. These sore throats are usually based on irritation of the mucous membranes in the throat and larynx area, which are caused by the insertion and removal of the mask. In most cases, the sore throat will persist only briefly and do not require further therapy. However, if breathing problems and shortness of breath occur in addition, medical supervision must be taken immediately to rule out life-threatening swelling and injury.