A laryngeal tube is a medical device designed to maintain an open airway, allowing a patient to receive oxygen. It functions as a supraglottic airway device, positioned above the voice box (larynx) without passing through it. This device provides a pathway for air to reach the lungs, particularly when a patient is unconscious or unable to breathe effectively. Its design also allows for mechanical ventilation during various medical interventions.
Purpose of a Laryngeal Tube
Laryngeal tubes are used in emergency medicine and anesthesia settings, especially when managing a “difficult airway.” Their straightforward placement makes them suitable for a range of medical providers, including emergency medical technicians and paramedics, who may not have extensive training in more complex airway procedures. This device serves as an alternative to other airway management techniques, such as mask ventilation or tracheal intubation.
The laryngeal tube is particularly useful in scenarios like cardiac arrest or when traditional endotracheal intubation has proven difficult or is not feasible. It can swiftly establish a secure airway without interrupting chest compressions during resuscitation efforts. The device also provides ventilation support for critically ill patients who are unconscious or unable to breathe. It is often used as a temporary measure or a bridge to more definitive airway control.
The Insertion Process
Placing a laryngeal tube involves a “blind insertion” technique, meaning the medical provider does not need a direct view of the vocal cords. The procedure begins with lubricating the device, then gently inserting the tube into the patient’s mouth and guiding it downwards along the curve of the palate. The tube is advanced until it meets definitive resistance, indicating its tip has reached the upper part of the esophagus.
Once in the correct position, two inflatable cuffs are inflated through a single pilot balloon and lumen. A larger oropharyngeal cuff expands in the middle section, sealing the area above the larynx and preventing air escape. A smaller esophageal cuff inflates at the tip, blocking the esophagus to prevent air from entering the stomach and reduce the risk of gastric contents entering the lungs. After cuff inflation, ventilation is initiated, and proper lung inflation is confirmed by observing chest rise and listening for breath sounds.
Comparison to Other Airway Devices
The laryngeal tube is one of several supraglottic airway devices, distinguishing itself from tools like the endotracheal (ET) tube and the laryngeal mask airway (LMA). A primary difference lies in their placement: laryngeal tubes and LMAs are supraglottic, sitting above the larynx, while an ET tube passes directly through the vocal cords into the trachea, or windpipe. This distinction impacts both the insertion technique and the level of airway security provided.
Laryngeal tubes and LMAs are generally easier and faster to place than ET tubes. Their blind insertion technique means providers do not need to visualize the vocal cords, unlike ET tube insertion, which often requires a laryngoscope to guide the tube. This makes supraglottic devices suitable for a broader range of medical personnel, including those with basic life support training.
While laryngeal tubes and LMAs offer efficient ventilation, an ET tube provides a more secure airway and enhanced protection against aspiration, which is the entry of stomach contents into the lungs. The ET tube’s placement directly in the trachea creates a more definitive seal, making it the preferred choice for patients requiring prolonged mechanical ventilation or those at high risk of aspiration. Although the esophageal cuff of a laryngeal tube helps reduce aspiration risk, it does not offer the same level of definitive protection as an ET tube.
Potential Complications
While considered safe when used by trained professionals, laryngeal tubes carry potential risks. Minor complications are common and may include a sore throat or hoarseness lasting for a few days after removal. Minor oral or pharyngeal trauma, such as mucosal injury, can also occur during insertion. These less severe issues are often transient and resolve without specific intervention.
More significant, though less common, complications can arise from improper placement or device malfunction. If the esophageal cuff does not adequately block the food pipe, air can enter the stomach, leading to gastric inflation, which may hinder effective ventilation. Inadequate ventilation can also occur if the seal around the larynx is insufficient or if the tube is dislodged.
Aspiration of gastric contents, while less likely than with mask ventilation due to the esophageal cuff, remains a concern. Other rare complications can include nerve palsies or pressure-induced lesions, though the overall incidence of serious complications is low.