Neuromuscular Electrical Stimulation and Dysphagia: A Clinical Update

Martin B. Brodsky, Ph.D., Sc.M., CCC-SLPAssistant ProfessorDepartment of Physical Medicine and Rehabilitation

October 1, 2015

Disclosures

Grant no.: 1K23DC013569-01Understanding and ImprovingDysphagia after Mechanical Ventilation

Royalties: MedBridge, Inc.

No affiliation with the devices and/or companies mentioned during this presentation.

Distribution of Research by Age

Roden & Altman (2013)

Prevalence of Dysphagia:Adults in the U.S.

• 1 in 25 adults affected annually• Estimated 9.44 0.33 million adults report a swallowing

problem.• Overall, 23% saw a health care professional for their

swallowing problem, and 37% were given a diagnosis.• Commonly reported etiologies

– Stroke: 422,000 77,000– Other neurologic causes: 269,000 57,000– Head and neck cancer: 185,000 40,000

• Mean days affected by a swallowing problem was 139 7• 12 lost workdays in the past year vs. 3.4 lost workdays for

those without a swallowing problem Bhattacharyya, 2014

Dysphagia Implications

• 3x increased risk of pneumonia in patients with dysphagia

• 12x increased risk of pneumonia in patients with aspiration

• 9x greater odds for death in patients who are aspirating thickened liquids.

Martino et al., 2005

Schmidt et al., 1994

Martino et al., 2005

History of NMES and Dysphagia:FDA Study Submission

1993-1995– Randomized 58 patients (thermal stimulation) and

109 electrical stimulation (sensory stimulation)

June 1995– Motor stimulation: 1 patient who failed sensory

stimulation– Continued randomization with 30 more patients to

determine number of treatments necessary

1995 - 1998– Non-randomized 725: 100% motor stimulation

History of NMES and Dysphagia:FDA Study Submission

Thermal(n = 58)

Sensory(n = 109)

Motor(n = 725)

Age in years, mean (range) 79 (47-98) 75 (36-101) 72 (<1-100)

Males, n (%) 33 (57) 55 (50) 373 (51)

Condition, n (%)

Stroke 36 (62) 63 (58) 347 (48)

Neurodegenerative disease 18 (31) 25 (23) 93 (13)

Neuromuscular (e.g., MG, myopathy) 0 ( 0) 0 ( 0) 10 ( 1)

Post-polio syndrome 0 ( 0) 0 ( 0) 2 (<1)

Respiratory 2 ( 3) 14 (13) 140 (19)

Cancer 2 ( 3) 3 ( 3) 56 (8)

Iatrogenic 0 ( 0) 1 ( 1) 16 ( 2)

Other 0 ( 0) 3 ( 3) 61 ( 8)

History of NMES and Dysphagia:FDA Study SubmissionSwallow Function

ScoreBest

PerformanceClinical

Implication

Level ofSwallow Deficit

0 Aspirates salivaNo solid or liquid is safe (aspiration highly likely or present)

Profound

1 Handles only salivaas above (candidate for PEG) Profound

2 Pudding, Paste, Ice, Slush

Liquids not tolerated unless pudding consistency

Significant

3 Honey Able to tolerate increasing levels of liquids

Moderate

4 Nectar Mild

5 Thin LiquidsNo coffee, tea, juice or water Minimal

6 Water Any viscosity is tolerated Normal

History of NMES and Dysphagia:FDA Study Submission

Results• BOTH sensory stimulation and motor stimulation were

more effective than thermal stimulation

• Sensory and Motor were “indistinguishable” after 2 treatments…and only to Level 4 (nectar)

• Sensory: 6 treatments; Motor: 5 treatments for similar improvements

• “For patients with severe dysphagia, electrical stimulation had a success rate of 97.5% of restoring swallowing patients past the point of requiring a PEG…”

History of NMES and Dysphagia:FDA Study Submission

And thus…2002: FDA 510(k) approval to market VitalStim (Chattanooga Group, Hixon TN) for external NMES in the laryngeal neck region.

Other devices on the market• eSWALLOW• Spectramed• Ampcare ESP• Phagenyx

LATEST EVIDENCE IN STROKE:CLINICAL TRIALS RESULTS

• 7 studies: quantifiable trials, including randomized and quasi-experimental trials that included a measureable variable.

• 20% INCREASE in swallowing score following treatment.

Summary Evidence – 2007:Meta-Analysis of Clinical Trials

Carnaby-Mann & Crary, Arch Otolaryngol Head neck Surg, 2007

Laryngeal elevation, weight gainPAS, diet, patient perception

Functional Oral Intake Scale(FOIS): Crary, Mann, & Groher, 2005

LEVEL 7: Total oral diet with no restrictionsLEVEL 6: Oral diet, multiple consistencies, no special

preparation, specific food limitationsLEVEL 5: Oral diet, multiple consistencies, requiring

special preparation or compensationsLEVEL 4: Oral diet, single consistencyLEVEL 3: Tube dependent with consistent oral intake

of food or liquidLEVEL 2: Tube dependent, minimal attempts of food

or liquidLEVEL 1: NPO

Latest Evidence:Permsirivanich et al., J Med Assoc Thai, 2009

RCT: NMES alone (n = 12) vs. Traditional therapy alone (n = 26)

PatientsNew stroke; persistent dysphagia >2 weeks

Therapy60 minutes5 days/week4 weeks

Latest Evidence:Lee et al., Ann Rehabil Med, 2014

RCT: NMES with traditional therapy (n = 31) vs. Traditional therapy alone (n = 26)

PatientsNew stroke

Therapy30 minutes5 days/week3 weeks

Latest Evidence:Park et al., Dysphagia, 2012

RCT: Motor NMES + effortful swallow (n = 9) vs. Sensory NMES + effortful swallow (n = 9)

Patients>1 month post-stroke; dysphagia

Therapy20 minutes3 days/week4 weeks

Vertical movement of the larynx

8 studies: Randomized and quasi-randomized controlled trials

Goals of the systematic review with meta-analysis

To determine:

1. Superiority of traditional therapy with NMES vs. Traditional therapy without NMES

2. Superiority of NMES alone vs. Traditional therapy alone

Summary Evidence – 2015:Meta-Analysis of Clinical Trials

Chen et al., Clin Rehabil, 2015

Superiority of traditional therapy with NMES vs. Traditional therapy without NMES (n = 6 studies)

ConfirmedSMD 1.27 (95% CI: 0.51, 2.02), p = 0.001

Summary Evidence – 2015:Meta-Analysis of Clinical Trials

Chen et al., Clin Rehabil, 2015

Superiority of NMES alone vs. Traditional therapy alone (n = 3 studies)

Insufficient evidenceSMD 1.27 (95% CI: 0.51, 2.02), p = 0.001

Summary Evidence – 2015:Meta-Analysis of Clinical Trials

Chen et al., Clin Rehabil, 2015

Latest Evidence:Suntrup et al., Intensive Care Med, 2015

RCT: Electrical Pharyngeal Stimulation (n = 20) vs. Sham control (n = 10)

PatientsAcute stroke, weaned from vent/trached, chronic dysphagia

Therapy10 minutes3 days

ResultsSuccessful decannulation in 72 hours• EPS: 15/20 (75%)• Sham: 2/10 (20%)

Remaining 8 in control received EPS• 1/8 (13%) t/f’d to rehab/no tx• 5/7 (71%) decannulated

Latest Evidence:Suntrup et al., Intensive Care Med, 2015

RCT: Electrical Pharyngeal Stimulation (n = 20) vs. Sham control (n = 10)

PatientsAcute stroke, weaned from vent/trached, chronic dysphagia

Therapy10 minutes3 days

EPS Control p-value

Time in hospital (days)

LOS, mean (SD) 43 (17) 42 (21) 0.95

ICU LOS, mean (SD) 38 (15) 39 (20) 0.92

Time (tx–to–d/c), mean (SD) 16 (12) 10 ( 6) 0.55

FOIS at hospital discharge

Tube dependent (1-3), n (%) 8 (40) 6 (60)0.30

Total oral intake (4-7), n (5) 12 (60) 4 (40)

SUMMARY ANDFINAL COMMENTS

Summary

Reviews and RCTs…• Presented limited numbers of studies

• Studies had low numbers of subjects

• Most studies have methodological shortcomings– Masking assessors only– Lack of details for interventions used

• DO lend support for use of NMES with traditional therapy

Final Thoughts

Research for NMES/EPS and dysphagia treatment is in its infancy

First RCT was 6 years after FDA approval of VitalStim

Future studies MUST be…• Methodologically well-controlled• Adequately detailed for replication• Larger to improved adequacy of statistical power