Clinical Application of the Kay Elemetrics
Swallowing Workstation

This Application Note has a clinical focus and is a brief description of how Speech Pathologists at University of North Carolina Hospitals have integrated the Kay Swallowing Workstation into their practice of assessing and treating dysphagic patients.

Introduction

As a fairly new clinician, I was first introduced to the Kay Swallowing Workstation at the Dysphagia Research Society Meeting in 1995. I was greatly impressed with the clinical application of this equipment, even though I did not fully understand all of its capabilities. I was immediately interested in purchasing the Kay Swallowing Workstation; however, I did not believe it was possible.

As I became more immersed in evaluating and treating patients with swallowing disorders, I became increasingly aware of the impact of our decisions. We are making recommendations that greatly affect a patient’s medical management as well as their quality of life. I became convinced that our facility needed the most sophisticated instrumentation available that would facilitate the services we provide. In short, we did not just want the Swallowing Workstation; we needed it to provide the highest quality intervention possible.

A proposal for the Kay Swallowing Workstation was submitted to our capital equipment board that included the percentage of dysphagic patients being treated, consequence of error in working with dysphagic patients, and future directions for intervention. Two months later our proposal was accepted. As our staff integrated the Kay Swallowing Workstation into our practice and learned to use Fiberoptic Endoscopic Evaluation of Swallowing (FEES), Surface Electromyography (SEMG), Cervical Auscultation (CA), respiration and swallow coordination assessment, tongue bulb manometry, and pharyngeal manometry, we became better dysphagia clinicians. We were able to make more accurate diagnosis, integrate more specific treatment strategies, and provide visual feedback to assist the patient with progress. It has allowed us to quantify our evaluation and treatment data to provide to referring physicians as well as enable us to have a more accurate picture of progress.

The Swallowing Workstation is a mobile unit allowing us to diagnose and treat patients in our clinic, at bedside, or in the fluoroscopy suite. Because the workstation is mobile, our physicians, nurses, and family members are often exposed to the type of work we are now doing with our patients. It has eliminated the need to transfer fragile or obese patients as well as allowed us to work with these patients in a timely manner.

Prior to the Swallowing Workstation, all of our Modified Barium Swallow Studies (MODBASWs) were recorded and kept on tape in the fluoroscopy suite. With the Swallowing Workstation we are afforded the luxury of recording and archiving our own studies. We can then print out specific pictures of the swallow (e.g., aspiration, residue, etc.), annotate the picture with therapist’s remarks, and then place it in the medical chart or give it to the patient, nurse, nursing home, or family member (see Figure 1; all figures are placed at the end of this note).

The Swallowing Workstation is used throughout our day. Listed below is an example of our daily routine.

Example of Daily Schedule Using the Swallowing Workstation  

8:00            Arrive at work, get coffee.

8:30            Distribute new consults.

9:00            Inpatient Evaluation (Mr. J. – Swallowing Workstation) run FEES, SEMG, and respiration assessment simultaneously.

10:00          Outpatient MODBASW (Swallowing Workstation) record fluoro study, print pictures of study, and generate report for nursing home MD and SLP.

11:30          Consult on 6^th floor.

12:15          Lunch (If I’m lucky).

12:45          Meeting

1:00            Outpatient dysphagia therapy (Mr. H. – Swallowing Workstation) set-up SEMG, FEES, CA, tongue bulb manometry, and respiratory trace feedback.

2:00            Generate Mr. H’s report from Swallowing Workstation on SEMG and tongue bulb manometry.

2:15            Inpatient FEES from 11:30 consult (Swallowing Workstation – 6^th floor).

3:00            Inpatient FEES – add on (Swallowing Workstation – 3^rd floor) run respiration assessment simultaneously.

4:00            Outpatient dysphagia therapy (Mrs. C. – Swallowing Workstation) set up tongue bulb manometry.

4:30 –         Generate Mrs. C.’s therapy report on tongue bulb manometry (Swallowing Workstation).

4:45 –         Gripe with colleagues about aching feet.

5:00 –         Leave (Let Swallowing Workstation rest up for tomorrow).

Explanation of UNC Hospital Application of the Workstation Components

We use seven different components of the Workstation at UNC. They are briefly described on the following pages so that the case studies that follow can be better understood. However, for much greater detailed information on the specific components, please see the other Application Notes that lend themselves to much greater technical detail.

Fluoroscopy Suite Application

The Workstation is rolled into the fluoroscopy suite and connected to the VCR. We can then run a basic fluoroscopy study or we can run other components simultaneously with the fluoroscopy study to obtain greater evaluation information. We record the studies on our Workstation, which archives them on the workstation’s computer. We pull up the studies by simply typing in the patient’s name and the computer finds the study on the designated tape. We review our studies frame-by-frame and in automated sequences. We freeze frame specific moments of the study (e.g., aspiration), write comments on the still, and then print out the color picture to place in charts or give to others. We can also record the studies simultaneously with other components of the workstation such as respiration, SEMG, or CA providing greater diagnostic information.

Fiberoptic Endoscopic Evaluation of Swallowing (FEES)

The Workstation is rolled into the patient’s room or into a clinic exam room. We can then perform and record our FEES with the same archiving ability as described in the Fluoroscopy Application as well as print annotated color pictures. We frequently use the FEES as our initial evaluation but it also can be used as a re-evaluation tool. FEES can be repeated without radiation exposure moving patients through the rehabilitative process and back to oral intake or to an upgraded diet more rapidly. We use FEES diagnostically and therapeutically to provide visual feedback. This feedback can help the patient learn how to effectively implement a supraglottic swallow or how to effectively clear one’s throat to eliminate penetration, etc. We frequently run the other components of SEMG and respiration tracing/assessment with FEES (see Figure 2). For more detailed information on FEES, please see Susan Langmore’s Application Note.

Surface Electromyography (SEMG)

SEMG is a way to provide visual feedback of muscle activity. We use SEMG primarily in dysphagia therapy. For our purposes, SEMG involves placing electrodes submentally. The patient can observe the waveforms created on the monitor to alter his or her own muscle activity. For example, if we are teaching an effortful swallow, we will encourage the patient to make a tracing with greater height as compared to his or her reflexive swallows (see Figure 3).  Throughout the session, particular swallows are tagged and saved. After the therapy session, all of the swallows tagged that have saved amplitude (microvolt) data are integrated into a report using the workstation software. SEMG has many other applications. For more detailed information on SEMG, please see Maggie Lee Huckabee’s Application Note. During our diagnostic sessions, we obtain information regarding muscle activity from SEMG, swallow function from FEES, and coordination of respiration simultaneously. The muscle activity demonstrated during the swallow assists us with recommendations regarding the length of the apneic period needed during the swallow.

Respiration Tracing

A nasal cannula is placed in the patient’s nose and then respiratory information (inhalation/exhalation) is displayed on the monitor. A green line indicates exhalation, a red line indicates inhalation, and a black line indicates apnea. Typically, an adult follows a respiration/swallow coordination pattern of exhale, swallow, exhale. The patient should experience an apneic period for the duration of the swallow. The duration of the swallow is apparent by reading the muscle activity waveform displayed from utilizing SEMG simultaneously (see Figure 4). A common problem seen with dysphagic patients is an inhalation following the swallow. The inhalation after the swallow poses a potential problem if there is penetrated material that might drop into the airway. We frequently work with patients on holding a sufficient apneic period for the swallow and then using the subglottic pressure in a marked exhalation after the swallow to assist with clearing the material. We also use the respiratory tracing as an incentive spirometer. The patient is encouraged to make “large red and green mountains and valleys” to increase respiratory support. The visual feedback provided on the workstation is often more helpful than the plastic hand-held spirometers. For more detailed information on coordination of respiration and swallowing, please see Bonnie Martin Harris’s Application Note.

Cervical Auscultation (CA)

A stethoscope diaphragm is placed on the patient’s neck over the thyroid lamina. The swallow sounds and subsequent breath sounds can then be heard through the workstation speaker. We use this auditory information to assess for maintenance of a clear airway during therapy when test boluses are being utilized. We also teach the patient to listen for clear airway sounds. We demonstrate clear breath sounds and also rhonchi breath sounds. If the patient hears rhonchi, she or he is instructed to cough and clear until clear breath sounds are heard. In addition, the acoustical information from the CA is displayed visually on the screen. Researchers in our field are currently investigating the duration of the acoustical swallowing signal to help determine which patients are in a high-risk category for aspiration. This information will not replace the objectivity of FEES or Fluoroscopic Swallow Studies; however, objective swallow studies are not readily available at all facilities and this type of information would assist clinicians with their decision making.

Tongue Bulb Manometry (TBM)

We use the TBM for patients with oral pressure deficits most commonly related to lingual weakness. The bulbs are placed on top of the posterior portion of the patient’s tongue. The patient is cued to either push his or her tongue to the roof of the mouth or to swallow and push the back of his or her tongue to the roof of the mouth during their swallow. The patient and clinician can gauge the amount of effort by referring to the visual feedback displayed on the screen (similar to SEMG feedback). The clinician can measure the amount of effort by tagging the highest pressure point. Subsequently, the workstation will give the pressure measurement in millimeters mercury (see Figure 5). Again, at the completion of therapy, the clinician can generate a report on the workstation from the saved tasks.

Manofluorography

Pharyngeal manometry is a newly developing area in our field. Pharyngeal manometry requires passing a catheter through the patient’s nose, pharynx, and upper esophagus. When the patient swallows, an increase in pharyngeal pressure occurs and the UES relaxes/opens. The changing pharyngeal and esophageal pressures created around the catheter is analyzed by the workstation. Thus, the clinician has access to objective information regarding the degree of pharyngeal weakness and/or the presence or absence of cricopharyngeal spasm, etc. This manometry is typically done in the fluoroscopy suite so that quick fluoro checks can assure the exact catheter placement. Some facilities may run the Modified Barium Swallow Study and pharyngeal manometry concurrently; however, this will differ among facilities. For more detailed information on manofluorography, please see John Salassa’s Application Note.

The following case studies illustrate our use of the workstation from evaluation through treatment.

Case Study #1

JB is an 84 year-old retiree. He was referred to our outpatient swallowing program six months status post CVA with a diagnosis of “severe pharyngeal weakness” and recurrent pneumonia. JB had a gastrostomy tube for total nutrition and had been in traditional dysphagia therapy for four months with no improvement.

Evaluation

A Fiberoptic Endoscopic Evaluation of Swallowing (FEES) was done during his initial visit and verified JB’s need for a gastrostomy tube secondary to significant aspiration of liquids, puree, and solids after the swallow.  Based on the FEES, it was our impression that JB exhibited decreased base of tongue retraction, decreased pharyngeal contraction, and decreased hyolaryngeal excursion.

During our initial evaluation, we also noticed that JB’s respiratory rate became increased and irregular with the introduction of a bolus. Thus, during the FEES, we simultaneously evaluated JB’s respiration and swallow coordination. JB frequently exhibited inspiration after the swallow that was problematic given his pharyngeal residue and penetration that had occurred during the swallow. In addition, JB exhibited an inability to hold an apneic period during the swallow as evidenced by the inspiration before the completion of the swallow.

Therapy

To target the pharyngeal weakness, we utilized Surface Electromyography (SEMG) with electrodes placed submentally. JB could then see a visual representation of the strength of his swallow. JB was encouraged to increase the strength of his swallow by increasing the amplitude of the waveform (“Make a taller mountain”). In addition, JB learned to perform a Mendelsohn maneuver employing the visual information from his efforts and from the therapist’s model. JB began exhibiting increased ability to swallow effortfully after three sessions, and his baseline swallow strength increased over the course of therapy.

To target respiration and swallow coordination, the nasal cannula was placed on JB, and utilizing the visual feedback of his respiratory phase, he was first cued to learn to hold his breath at the level of the glottis. This was displayed visually as a black straight line on the monitor. Then he was cued to swallow and hold the tension at the level of his voice box for the entire swallow in order to achieve a black straight line for the duration of his swallow. JB learned this quickly. Next, we focused on drawing JB’s attention to using the subglottic pressure built up during the swallow as an exhalation force after the swallow. To do this correctly, he should see a black straight line during the swallow followed by a green hill after the swallow (exhalation). Again, JB learned this quickly and this behavior generalized over the course of about 12 sessions.

After every 4-5 sessions, a simultaneous FEES, SEMG, and respiratory analysis was performed to assess for improvement. The frequent reassessments were done so that we could move through treatment aggressively and food could be initiated as soon as safely possible. After four weeks, JB was able to start consuming limited amounts of puree and honey-thick liquids. He was to alternate liquid and puree boluses and to double swallow after each sequence. During trial feeds of puree and honey thick liquids, JB implemented his strategies and we utilized CA to reassure clear airway maintenance.

After six weeks in the program he was able to consume puree and honey-thick liquids for nutrition. Tube feeds were weaned appropriately during this time. After nine weeks in the program, he was able to upgrade to soft solids and thin liquids still utilizing the above mentioned strategies.

JB was discharged from treatment after 12 weeks and encouraged to continue his exercises in his previously established home program. After 16 weeks, JB's lungs were still clear and his gastrostomy tube was removed. Six months after the gastrostomy tube had been removed, JB had not experienced pneumonia, his lungs were clear, and he reported much pleasure in being able to eat again.

Case Study #2

KT is a 51 year-old female who has a diagnosis of Chronic Obstructive Pulmonary Disease (COPD). She had been admitted to the hospital five times with lower lobe pneumonia. The Speech Pathology Department had been consulted to rule out prandial aspiration. A Modified Barium Swallow Study (MODBASW) was done during admission three and four. Both Modified Barium Swallow Studies were fully challenging studies and revealed no aspiration or patterns of oropharyngeal dysphagia. During the fifth admission, Speech Pathology was asked again to assess KT’s swallowing because nursing had observed choking during lunch. Given the past two normal MODBASWs, we were more suspicious of possible esophageal regurgitation (reflux); however, we agreed to assess one last time. This time, the Kay Workstation was taken to bedside. FEES, SEMG, and respiration assessment were run simultaneously while KT ate an early dinner.

Evaluation

The evaluation revealed a slightly increased respiratory rate during the first five minutes of her meal. As she continued to eat, her respiratory rate continued to increase. After about ten minutes of eating, she began to present a delay in swallow initiation to the level of the pyriform sinuses with thin liquids. Then KT began to silently (contrary to the coughing seen at lunch?) aspirate thin liquids during the swallow. The respiratory trace exhibited a decrease in the duration of the apnea as compared to the apneic duration of the initial swallows.

Our impression is that KT’s swallow initiation was inhibited secondary to her increased physiologic load of maintaining adequate oxygen and carbon dioxide exchange. In addition, the increase in respiratory rate and subsequent decrease in apneic duration (vocal fold adduction) resulted in aspiration.

Treatment

To target KT’s aspiration problem, we implemented four things. First, we taught KT to focus on a volitional swallow as opposed to relying on her reflexive swallow. Second, we helped KT increase her awareness of holding an apneic period during the entire swallow (at the level of the glottis). Third, we started her on a schedule of smaller more frequent meals. Fourth, she was asked to pace her eating so that her respiratory rate could be better regulated.

Teaching a volitional swallow involves instructing the patient to use visual feedback obtained from the FEES in order to maintain oral control of the bolus preventing spill into the pharynx before the swallow. In other words, the patient is instructed to think about holding the liquid in the front of her mouth and then swallow. While looking at the monitor, she should not see the green liquid falling back in her throat before “white-out”. We had to fatigue KT before we could demonstrate the delay problem; however, KT learned the volitional swallow quickly and successfully.

To increase KT’s awareness of holding an apneic period for the swallow, we used the visual feedback from the respiratory trace and the SEMG concurrently. Similar to JB, we encouraged KT to hold a straight black line to achieve apnea for the entire time there was swallowing activity as seen on the SEMG display. In conclusion, after about two sessions of coaching on volitional swallow, holding an apneic for the swallow, and pacing oral intake; KT exhibited no aspiration on her follow-up FEES.

Summary

Both cases presented are cases where traditional therapy and traditional diagnostics failed to appropriately serve these patients. Instrumentation that could provide FEES, SEMG, respiration tracings, CA, and oral pressure biofeedback was necessary.

There is a lot to be said for clinical judgement, but instrumentation can make us much better clinicians. The Kay Workstation has afforded us the ability to optimally serve the needs of our dysphagic patients by decreasing our consequence of error and most importantly helping our patients achieve their highest level of quality of life.

On a personal note, I would like to add that our profession has evolved into this specialty of evaluating and treating patients with dysphagia. Thus, the impact we have on our patient’s health and quality of life has increased dramatically. We should not be intimidated by using instrumentation or asking our employers for instrumentation. Physical Therapists have been using instrumentation/equipment for a long time, and I would pose that we also deserve instrumentation given the important role eating and nutrition plays in our patient’s lives.    

References

The above Application Note was intended to offer suggestions for the clinical application of the Kay Workstation. For references on specific components of the Kay Workstation, please see the other Application Notes.

	Figure 2: Dysphagia evaluation in which a FEES procedure was performed concurrently with sEMG and respiration traces. All data are time-linked.

 

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*Ms. Hiss is currently a doctoral student at East Carolina University, Greenville, NC. She was at UNC Hospitals when the Application Note was written.