Assessment of Dysphagia

Original Editor - Ewa Jaraczewska based on the course by Srishti Banerjee

Top Contributors - Ewa Jaraczewska and Jess Bell  

Introduction

A thorough dysphagia assessment can help with the early identification, management, prevention and mitigation of complications related to swallowing difficulties. It facilitates optimal nutritional support and can enhance overall patient health outcomes.

However, according to Freeman-Sanderson et al., less than one-third of health professionals using dysphagia protocols in intensive care units (ICU) complete formal dysphagia training. Yet competency training in dysphagia screening for healthcare practitioners can benefit patients with neurological, cardiopulmonary and gastrointestinal conditions, and patients post-endotracheal intubation or tracheostomy who are affected by oropharyngeal dysphagia. Donovan et al. advocate for dysphagia screenings to be performed by a range of healthcare professionals to accelerate the screening process of patients with acute stroke. They state that the "absence of consensus on the best screening instrument does not mean no screening should be performed." This article discusses the most common non-instrumental and instrumental dysphagia assessments.

Dysphagia Screening

Two general types of dysphagia screening and assessments are currently available: non-instrumental and instrumental. Non-instrumental tests include the dry swallowing test, the water swallowing test, the 3-ounce water swallow test, the cough reflex test, and bedside swallowing evaluation. Instrumental examinations include Videofluoroscopic Swallow Study (VFSS) and Fiberoptic Endoscopic Evaluation of Swallowing (FEES). The instrumental assessments are not always available, accessible, or feasible.

For a patient who experiences dysphagia, the first and most important step is selecting the appropriate test to perform.

Patient History

When taking the patient's history, the following standardised tools can be helpful:

• Eating Assessment Tool 10 (EAT 10)
  • It is used to screen for dysphagia and aspiration risk
  • Can be completed by the patient, caregiver, or during an interview with a clinician
  • Each question is rated on a scale of 0 (no problem) to 4 (severe problem)
  • See Eating Assessment Tool 10 (EAT 10) here
• Dysphagia Handicap Index (DHI)
  • Completed by the patient
  • Self-assessment questionnaire
  • Includes 25 statements to assess functional, physical, and emotional aspects of life of the patients with dysphagia
  • See Dysphagia Handicap Index (DHI) form here

Observation

All rehabilitation professionals should become competent to perform this part of the dysphagia evaluation. Key observation points in the evaluation of the patient with dysphagia include (1) general health status, including body mass index, (2) posture, (3) oral-motor skills (rotatory chew movement including lateral chew, jaw jerk or suck and swallow as the patient chews), (4) inspection of oral cavity for oral cavity ulcerations, exophytic growths, abnormal motion of the palate, mucosal drying, tongue appearance and motion, and dental status, (5) nasal evaluation to rule out local tumours or postnasal drip.

Palpation

All rehabilitation professionals can complete palpation examination for the neck area. Look for any tenderness, masses or swelling which can obstruct the flow of the food.

Speech-language pathologists use palpation in clinical swallow evaluation. In the 4-finger method, one finger is placed behind the mandible, one on the hyoid bone and two on the upper and lower borders of the thyroid cartilage:

• It is used to assess submandibular, hyoid and laryngeal movements.
• It offers information about "when and how many times the patient has swallowed and a rough estimate of the timing and completeness of the swallow."

General Rules

• Determine the best seating position for a patient based on observing the person's postural strengths and needs.  Look at the trunk position, shoulder alignment, and head control. Example: A patient with extreme extensor spasticity may not do best in the upright sitting position with hip and knee flexion.  
• Perform oral hygiene before administering water. Proper hygiene consists of brushing the teeth with a toothbrush and appropriate toothpaste and rinsing the mouth with a solution based on hydrogen peroxide.

Clean water that can enter the respiratory tract while drinking is not a threat! The threat comes from food remains and bacteria that are left in the mouth due to poor or lack of oral hygiene.

Neurological Assessment

• Assess the state of arousal state and the cognitive performance of the patient.
• Perform sensory examinations:
  • Anterior two-thirds of the tongue
  • Posterior one-third of the tongue
  • Hard palate
  • Soft palate
  • Posterior pharyngeal wall
  • Laryngeal region.

• Complete a gross neurological examination, specifically cranial nerves, from 9th to 12th.

Non-instrumental Dysphagia Tests

Dry Swallowing Test

All rehabilitation professionals should become competent to perform a dry swallowing test. General steps are as follows:

• Positioned the patient in a comfortable position. It can be preferably sitting with a well-supported back and feet.
• The mouth of the patient can be moistened with cold water.
• Ask the patient to swallow repeatedly.
• Results: during a period of 30 seconds, three or more dry swallows are normal. The test will provide information about laryngeal elevation.

Water Swallowing Test (WST)

• Physicians, nurses, SLPs or qualified clinicians can perform water swallowing test
• It is a standardised test, but the amount of water given varies depending on the person performing it.
• The patient drinks 30 ml or 100 ml of water as quickly as possible without interruption

Results:

• The examiner observes the number of swallows
• The average bolus size is counted by dividing 100 mL by the number of swallows.
• The swallowing speed (mL/s) is calculated by dividing 100 mL with the drinking time measured in seconds.

Results:

• >20 mL (100 mL completed with less than five swallows) is considered normal.
• The patient passes the test if they do not cough during drinking, 1 minute after drinking, or during interrupted drinking. Removing the glass from the lips is considered interrupted drinking.
• The time measurement is stopped when a patient coughs during drinking. The swallowing speed is calculated using the amount of water the patient drank before coughing.
• Additional parameters recorded are (1) wet–hoarse voice after drinking and (2) average drinking bolus size.

Modified Water Swallowing Test (MWST)

• Speech language pathologists or qualified clinicians after competency training can perform this test.
• MWST contains the following steps:
  • The patient is given 3 ml of cold water on the oral floor and instructed to swallow the water
  • If possible, the patient is asked to perform 2 dry (saliva) swallows.
  • If the patient meets score 4, a maximum of 2 additional attempts (a total of 3 attempts) is made.
  • The worst assessment is recorded as the final result.

Results:

1. Inability to swallow with choking and/or breathing changes
2. Swallow occurred, but with breathing changes
3. Swallow occurred, but with choking and/or wet hoarseness
4. Swallow successfully
5. Swallow successfully with the ability of additional dry swallowing twice in the 30s

Bedside Swallowing Evaluation (BSE)

• Completed by the speech-language pathologists (SLPs)
• Assess swallowing function and airway safety during swallowing
• Helps to identify the risk of aspiration
• Used by SLPs to provide feeding recommendations
• According to Moss et al., "BSEs are relatively inaccurate for the detection of aspiration"

Standardised Protocol for BSE evaluation includes the following elements:

• review of the patient’s medical record
• physical examination:
  • Lip movement and seal
  • Tongue movement and strength
  • Volitional cough strength
  • Dentition
  • Voice quality
  • Amount of assistance required with feeding
• The patient is positioned as upright as possible
• The SLP administered five standard consistencies: (1) ice chips, (2) nectar thin liquids, (3) pureed solids, (4) thin liquids, and (5) solids in successive boluses that increased in size
• The SLP administers all boluses unless they consider it unsafe based on the patient's response
• The SLP observes five clinical signs of aspiration after each bolus: cough, throat clearing, change in vocal quality, wet breath sounds, or stridor.

Cough Reflex Test (CRT)

• Administered by the speech-language pathologists (SLPs)
• It is a screening tool to evaluate the integrity of the cough response to airway invasion.
• Evaluates the risk of silent aspiration because it provides information about the integrity of upper airway sensation, which is one of the factors contributing to patients’ risk of silent aspiration.
• Patient inhales a cough-evoking mist of citric acid–physiological saline via a nebulizer to induce coughing.
• Clinicians record the presence, absence and number of coughs elicited and self-reported ratings of the perceived intensity of airway irritation (the urge to cough).
• CRT's methodology and protocols lack consensus in the literature.

This optional video demonstrates elements of the clinical swallowing exam:

Instrumental

Videofluoroscopic Swallow Study (VFSS)

A videofluoroscopic swallow study is also known as the modified barium swallowing test (MBST) and is considered the gold standard in diagnosing oropharyngeal dysphagia.

• Performed by experienced SLPs with radiologist or medical radiological technologist.
• May require advanced competency certification in Videofluoroscopic Assessment of Adult Swallowing Disorders.
• It is a radiographic assessment of swallowing.
• It should be a custom-tailored technique designed by radiologists and swallowing therapists based on the patient’s clinical history and symptoms."
• A physician’s order is required to initiate a VFSS.
• A clinical swallow assessment must be completed before a VFSS is administered.

Fiberoptic Endoscopic Evaluation of Swallowing (FEES)

• Administered by SLPs trained in FEES examination.
• Because it requires professionals to perform the test, the test might not be feasible for community screening.
• Fiber-optic or distal chip endoscopes are used for the evaluation.
• The endoscope is inserted through the nose to observe the pharynx and larynx when the individual is swallowing saliva with and without food of varying consistencies.
• May induce pain and discomfort.
• Every institution must develop a protocol for FEES administration.
• Video and sound are recorded and used to determine a penetration-aspiration scale (PAS) score for each of the boluses administered:
  • PAS is an 8-point, equal-appearing interval scale describing penetration and aspiration events:
    • A score of 6 or more indicates aspiration
    • A score of 6 or 7 indicates nonsilent aspiration
    • A score of 8 represents silent aspiration

High-Resolution Pharyngneal Manometry (HRPM)

• Performed by Speech-Language Pathologists (SLPs) with proper training in HRPM

• It helps to understand the mechanism of oropharyngeal dysphagia.
• It identifies individuals at risk for dysphagia in a neurological disorder like Parkison’s disease.
• It defines pharyngeal lumen occlusive pressures, hypopharyngeal intrabolus pressures, and upper oesophagal sphincter (UES) function.
• Can be performed without ingesting any barium bolus.
• It is a safe assessment for dysphagia patients at high risk of aspiration.
• It detects changes in swallowing-related pressures in patients with early Parkinson's disease before the onset of dysphagia's signs and symptoms.

Barium Swallow

• The examination is performed by a radiologist
• Barium swallow or oesophagogram is the gold standard test in assessing the anatomical characteristics of the oesophagus.
• Evaluates oesophagal dysphagia using real-time fluoroscopy and barium.
• Can help to identify any morphologic and motility abnormalities in the pharynx and oesophagus.
• Rarely used as a stand-alone investigation

Ultrasound

• Can be performed by highly skilled SLPs, who completed competency to achieve independent practitioner status.
• Allows visualisation of soft tissue structures of the mouth (tongue and floor of the mouth).
• Assess swallowing kinematics of the tongue, hyoid, larynx, and lateral pharyngeal wall.
• Assess the hyoid bone displacement during swallowing.
• Allows morphometric assessment (measurements of muscle thickness or cross-sectional area) of muscle groups related to swallowing, such as the tongue, masseter, and submental muscles.
• Less invasive than VFSS or FEES

Real-Time Magnetic Resonance Imaging (RT-MRI)

• RT-MRI is performed by a radiologist or a radiology technologist
• No radiation exposure.
• Assess symmetry and amplitude of movements of velum, faucial pillars, tongue, epiglottis and cricopharyngeous.
• Provides images from the sagittal, coronal and axial planes:
  • Sagittal plane: posterior movement of the tongue and its compression on the soft palate, the elevation of the hyoid bone, the elevation of the larynx and lid action of the epiglottis
  • Coronal plane: the symmetrical movements of the faucial pillars and pharyngeal constrictor muscles
  • Axial plane: assessing three anatomical landmarks based on their role in swallowing: soft palate, epiglottis and cricopharyngeous muscle.

Resources

• Dysphagia Ramblings
• Dysphagia Resource Collection
• 9 free swallow assessment tools
• EAT-10 swallowing screening tool in 36 languages