Intubation is the routine medical procedure of placing a flexible plastic tube (endotracheal tube or ETT) through the mouth or nose into the windpipe (trachea) to assist breathing. Dysphagia is the medical term for difficulty swallowing food, liquids, or saliva. Intubation is a recognized risk factor for developing temporary or persistent swallowing problems following the tube’s removal (extubation). This post-extubation dysphagia (PED) can affect a significant portion of patients requiring mechanical ventilation, with reported rates ranging from 3% to over 60%. The mechanical presence of the ETT and the critical illness requiring its use disrupt the delicate coordination of the swallowing mechanism.
How Intubation Affects the Swallowing Mechanism
The physical presence of the endotracheal tube directly irritates the sensitive tissues of the throat and voice box, which are crucial for swallowing. The tube passes directly between the vocal cords and through the larynx, causing mucosal inflammation and swelling (edema). This mechanical trauma can lead to diminished sensation in the throat, impairing the protective reflexes needed to prevent food or liquid from entering the airway.
The cuff at the end of the ETT, which is inflated to seal the airway, exerts pressure on the surrounding pharyngeal and laryngeal walls for the duration of the intubation. Prolonged pressure can cause injury, potentially leading to paresis or paralysis of the vocal cords by compressing the recurrent laryngeal nerve. When the vocal cords cannot close properly, the airway is left unprotected during the act of swallowing.
Beyond the direct mechanical effects, patients requiring intubation are often critically ill, leading to generalized muscle weakness and deconditioning. The muscles of the tongue, throat, and voice box can weaken from disuse during the period of mechanical ventilation and deep sedation, contributing to swallowing dysfunction.
This overall weakness, combined with the lack of practice, can disrupt the complex, coordinated timing between breathing and swallowing, further increasing the risk of material entering the airway. The risk of developing dysphagia is associated with the duration of intubation, with a higher likelihood seen in patients intubated for longer periods, particularly beyond seven days.
Recognizing Symptoms of Post-Intubation Dysphagia
Identifying post-intubation dysphagia begins with observing specific behaviors immediately after the breathing tube is removed and during initial attempts to eat or drink. One of the most noticeable symptoms is a wet, gurgly, or hoarse voice quality after speaking or swallowing, indicating that secretions or food residue may be pooling near the vocal cords. Patients may also experience a weak or ineffective cough, which is the body’s primary defense mechanism for clearing the airway.
During mealtimes, an individual with post-intubation dysphagia might cough, choke, or gasp for breath while eating or drinking, a clear sign that the swallowing reflex is impaired. Some people report the sensation of food or liquid getting stuck in their throat, often requiring repeated attempts to swallow or excessive throat clearing. A feeling of breathlessness or a change in breathing pattern during or immediately after a meal can signal difficulty coordinating the breath and swallow.
Other signs may be more subtle or emerge later, such as unexplained fever or recurrent chest infections. These can result from silent aspiration—when food, liquid, or saliva enters the lungs without triggering a cough reflex. The patient might also start eating slower than usual, refuse certain textures of food, or have difficulty managing their own saliva, leading to drooling or the need for frequent spitting. Early recognition of any of these symptoms is important for preventing complications like aspiration pneumonia.
Recovery and Management of Swallowing Difficulties
Post-intubation dysphagia is often a temporary condition, and most patients experience a spontaneous improvement in their swallowing function over time. For many, the swelling and irritation resolve within days or a few weeks after extubation, allowing them to resume a normal diet. However, a significant number of patients, particularly those with prolonged intensive care unit (ICU) stays, may have symptoms that persist longer, sometimes for months after hospital discharge.
Management begins with a formal swallow screening, often performed by nursing staff or a Speech-Language Pathologist (SLP) within 24 to 72 hours of tube removal. If swallowing difficulty is suspected or confirmed, an individualized treatment plan is developed, often involving instrumental assessments like a Fiberoptic Endoscopic Evaluation of Swallowing (FEES). These objective tests help precisely diagnose the nature of the impairment, determine if aspiration is occurring, and guide therapeutic decisions.
A primary management step involves modifying the diet texture to ensure safe consumption, which may mean using thickened liquids or pureed foods temporarily to prevent aspiration. The SLP also prescribes specific swallowing therapy exercises and maneuvers, such as postural changes like a chin-down tuck or effortful swallows, to strengthen the weak muscles and improve airway protection. While most survivors fully recover, those with a longer ICU stay may require ongoing monitoring and rehabilitation.