Diagnostics: Swallow Evaluation

Swallowing is a complex reflex with profound impact on one’s health. Swallowing abnormalities can threaten not only the sociability of eating but also poor nutrition, dehydration, and aspiration pneumonia. Various techniques of evaluating the safety and effectiveness of one’s swallow function are described below. Each technique has its advantages and disadvantages, and no technique perfectly demonstrates all causes of swallowing dysfunction. A physician therefore chooses which swallow evaluation technique based on currently available information.

Bedside Swallow Evaluation

A bedside swallow evaluation, also known as a clinical swallow assessment, is a crucial procedure conducted to determine a patient's ability to safely swallow food and liquids. Here is an overview of the key components of this evaluation:

1. Patient History Review: Clinicians begin by gathering information regarding the patient's medical history, including any previous swallowing difficulties, neurological conditions, head and neck surgeries, and current medications that may affect swallowing.

2. Observation of Oral Structures: The clinician assesses the oral cavity, including the lips, tongue, and throat, to identify any anatomical abnormalities, weakness, or asymmetries that may influence swallowing.

3. Cognitive and Sensory Evaluation: The patient's awareness, attention, and ability to follow commands are evaluated. This includes assessing sensory perception in the oral cavity, which is vital for safe swallowing.

4. Swallowing Trials: The patient is given varying consistencies of food and liquids to swallow, often starting with ice chips and progressing to thicker liquids and solid foods. The clinician observes for signs of difficulty, such as coughing, throat clearing, or changes in breathing patterns.

5. Assessment of Swallowing Mechanics: The clinician evaluates the timing and coordination of the swallowing process. This includes assessing the oral phase, pharyngeal phase, and esophageal phase of swallowing.

6. Monitoring for Aspiration: A crucial aspect of the evaluation is to identify any signs of aspiration, where food or liquids enter the airway instead of the esophagus. This is often monitored through clinical signs, as well as using stethoscopes or other tools if needed.

7. Recommendations and Referral: Based on the findings, the clinician provides recommendations regarding dietary modifications, the need for further diagnostic testing (such as a videofluoroscopic swallow study), and referrals to other specialists, like a speech-language pathologist or dietitian.

The results of a bedside swallow evaluation help to create an individualized care plan to ensure safe swallowing and prevent complications such as aspiration pneumonia or nutritional deficiencies. A bedside swallow evaluation is an inexpensive and quick estimation of swallow function, but it may not adequately assess swallow function across various food consistencies or identify underlying anatomical and physiological issues. As such, it is commonly used as an initial screening technique.

Modified Barium Swallow (also known as speech swallow or cookie swallow)

The procedure typically involves the use of fluoroscopy, a real-time imaging technique, along with the oral intake of barium-containing substances that can be visualized on X-ray.

The evaluation begins with the patient positioned comfortably in front of a fluoroscopy machine. A speech-language pathologist or a trained healthcare professional prepares a series of barium-infused food items and liquids, typically varying in texture and consistency (e.g., thick liquids, puree, solid food).

During the procedure, the patient is instructed to swallow the barium preparations while a continuous X-ray is taken. The healthcare professional closely observes the movement of the barium through the oral cavity, pharynx, and esophagus. Key aspects examined include bolus formation, the timing and coordination of swallowing, the potential for aspiration (the entry of food or liquid into the airway), and the effectiveness of the swallow response.

As the fluoroscopy captures real-time images, the evaluator may modify the consistencies or techniques used to optimize swallowing for the patient. Observations made during the study help identify any abnormalities in the swallowing mechanism, such as delayed swallow reflex, incomplete clearance, or structural issues.

After the examination, the imaging is reviewed, and a report is generated detailing the findings. Recommendations may be provided regarding dietary modifications, swallowing strategies, or further evaluations if needed. The results from this evaluation may be helpful in developing an appropriate treatment plan for individuals with swallowing disorders related to the mouth and throat. A modified barium swallow study may have limitations in evaluating dysphagia due to its reliance on real-time imaging, which may not capture intermittent or subtle swallowing abnormalities that occur infrequently, its lack of direct visualization of the lining of the throat, and that it does not evaluate the esophagus.

Barium Swallow (also known as barium esophogram)

A barium swallow study, also known as a fluoroscopic esophogram, is an imaging test used to evaluate the esophagus (but not the throat or oral cavity) and any abnormalities within it. The procedure involves the patient swallowing a barium contrast material, which is a radiopaque substance that enhances the visibility of the esophagus on X-ray images.

During the study, the patient is typically positioned upright in front of a fluoroscopy (x-ray) machine. The radiologist or technologist will instruct the patient to drink the barium solution, which may have a chalky texture. As the barium passes through the esophagus, several real-time X-ray images are captured to make a video, allowing the healthcare provider to observe the esophagus's structure and function.

The procedure allows for the assessment of various conditions related to swallowing difficulties (dysphagia), including esophageal strictures, abnormal motility of a bolus through the esophagus, tumors, or other anatomical abnormalities. When reflux of stomach contents up the esophagus is demonstrated during a barium swallow study, the patient is shown to have reflux. The absence of reflux during the study, however, does not guarantee that the patient does not have reflux at other times. The barium swallow study can highlight issues such as abnormal motility of a bolus through the esophagus, the presence of blockages, or anatomical abnormalities.

Patients may be instructed to avoid food and drink for several hours before the test to ensure optimal imaging. After the procedure, it is common for patients to be advised to drink plenty of fluids to help clear the barium from their system. Side effects are generally minimal but may include temporary constipation or white stool until the barium is fully eliminated.

A fluoroscopic esophogram study has limitations and disadvantages, including radiation exposure, the inability to visualize esophageal motility disorders directly, and the possibility of false negative results if the imaging techniques are not performed correctly or if the patient’s problem is not active at the time of the study.

Modified Barium Swallow Study vs. Barium Swallow Study

Variants of contrast media

In some cases, there may be reason not to use barium as the contrast agent in a modified barium swallow study or a barium swallow study. One example is when there is concern for possible leakage from the pharynx or esophagus to the space outside of the lungs, the mediastinum, since barium is highly inflammatory to these tissues. Gastrograffin is a water soluble contrast material that does not have the same reaction in the mediastinum, but it does cause an intense and potentially fatal reaction within the lungs, so it is not used when there is concern for aspiration. Omnipaque is a contrast medium typically used in IV form for a CT scan with contrast, but sometimes a small amount of omnipaque is given by mouth as a modification of the modified barium swallow study or the barium swallow study to make a swallowing assessment without the same risks as with barium and gastrograffin.

FEES (Fluoroscopic Endoscopic Evaluation of Swallowing)

Flexible endoscopic evaluation of swallowing (FEES), is a diagnostic procedure used to assess swallowing function. This evaluation provides direct visualization of the anatomy and physiological processes involved in swallowing and helps identify any abnormalities that may lead to dysphagia, or difficulty swallowing.

During the procedure, a flexible endoscope, which is a thin, flexible tube with a camera and light source, is inserted through the nasal passage and passes down the throat. This positioning allows the speech and language pathologist to observe the pharyngeal and laryngeal structures in real-time. Patients may be asked to swallow various food and liquid consistencies while the endoscope captures video footage of the swallowing process.

Flexible endoscopic evaluation of swallowing is advantageous as it is safe, may be performed by a speech pathologist without x-ray machines or a radiologist, and provides real-time observation capability. A flexible endoscopic evaluation of swallowing may, however, be limited by patient tolerance and the subjective interpretation of findings by the clinician.

Esophagogastruduodenoscopy (EGD, or “Upper Endoscopy”)

An esophagogastroduodenoscopy (EGD) is a medical procedure that allows a gastroenterologist physician to visualize and examine the upper digestive tract, which includes the esophagus, stomach, and the duodenum (the first section of the small intestine). During the procedure, a flexible tube known as an endoscope, equipped with a camera and light, is inserted through the mouth and gently advanced through the esophagus into the stomach and duodenum.

Before the EGD, the patient is usually given instructions to fast for several hours to ensure that the stomach is empty. The procedure is typically performed in a clinic or hospital setting and may be done under sedation to ensure comfort. Patients are monitored throughout the process.

Once the endoscope is in place, the physician can visually assess the lining of the upper gastrointestinal tract for any abnormalities such as inflammation, ulcers, tumors, or bleeding. Balloon dilation of a stricture (narrow area) may be undertaken as part of the EGD. Additionally, small tissue samples (biopsies) can be taken for further analysis if necessary.

The entire procedure generally lasts between 15 to 30 minutes. After the EGD, patients may experience a sore throat or mild discomfort, but these symptoms usually resolve quickly. It is common for patients to be advised to rest for a short duration following the procedure until the sedation wears off. The patient may not drive, operate machinery such as power tools, or make important decisions for the remainder of the day after the procedure.

Esophagogastroduodenoscopy can be limited in evaluating dysphagia due to its inability to assess functional disorders of swallowing, which may not be directly observable through endoscopic visualization and that EGD does not evaluate the mouth or throat during swallowing..