Smart-e-Pants: Intermittent Electrical Stimulation for the Prevention of Pressure

UlcersChester Ho, MD

Head and Associate ProfessorDivision of Physical Medicine & Rehabilitation

Department of Clinical NeurosciencesUniversity of Calgary

Calgary, Canada

2

AIHS Team in Smart Neural Prostheses:

Neuroscientists, Engineers, Cell Biologists, Computer Scientists, Neurosurgeons, Physiatrists, Biostatisticians

Principal Investigators

Project SMART

Objectives

• To describe the scope of problems with pressure ulcers

• To review the use of intermittent electrical stimulation in the prevention of pressure ulcer

• To discuss the design of Smart-e-Pants and its feasibility testing

WHAT IS A PRESSURE ULCER?

Definition

• A pressure ulcer is localized injury to the skin and/or underlying tissue usually over a bony prominence, as a result of pressure, or pressure in combination with shear. A number of contributing or confounding factors are also associated with pressure ulcers; the significance of these factors is yet to be elucidated*.

*National Pressure Ulcer Advisory Panel/European Pressure Ulcer Advisory Panel

Stage IV Pressure Ulcer

Big problem? Yes!

• US prevalence data by hospital setting:– acute hospital: 3-11% (9.2% in a study of 148

acute care hospitals) (Meeham 1990)

– rehabilitation hospital: 6-40% – skilled nursing facility. 5-26%– home care: 20%– hospice: 13%

Expensive problem? Yes!

• Cost of care: $9.1 – 11.6 billions spent per year in US (ARHQ)

• CMS not paying for hospital-acquired stage III or IV pressure ulcers since Oct 2008

Are they avoidable?

• Incidence not decreasing in US• Expert consensus – most are avoidable but some are

not (Black 2011)

• Many risk factors are reversible – therefore important to explore reversible factors

• Current prevention techniques are passive and do not aim to actively reverse any underlying tissue health risks… so what can we do?

SMART-E-PANTSIntermittent Electrical Stimulation (IES)

• Proof-of-principle established in short-term experiments in animals (rats) and human volunteers (intact, spinal cord injured): Increasing tissue oxygenation Redistributing pressure around bony prominences Increasing muscle mass

Using Intermittent Electrical Stimulation as a Means of Prevention

How Smart-e-Pants Works

(b)

(a)

left

right

left

right

sustained train of pulses during stimulus ON

bursts of pulses during stimulus ON

simultaneous left-right activation

alternating left-right activation

left

right

left

right

sustained train of pulses during stimulus ON

bursts of pulses during stimulus ON

left

right

left

right

left

right

left

right

sustained train of pulses during stimulus ON

bursts of pulses during stimulus ON

simultaneous left-right activation

alternating left-right activation

Gluteus Maximus

Ischial tuberosity

Gluteus maximusmotor point

Gluteus Maximus

Ischial tuberosity

Gluteus maximusmotor point

(b)

(a)

left

right

left

right

sustained train of pulses during stimulus ON

bursts of pulses during stimulus ON

simultaneous left-right activation

alternating left-right activation

left

right

left

right

sustained train of pulses during stimulus ON

bursts of pulses during stimulus ON

left

right

left

right

left

right

left

right

sustained train of pulses during stimulus ON

bursts of pulses during stimulus ON

simultaneous left-right activation

alternating left-right activation

Gluteus Maximus

Ischial tuberosity

Gluteus maximusmotor point

Gluteus Maximus

Ischial tuberosity

Gluteus maximusmotor point

“ON”“OFF”

10 minutes10 sec

“ON”

Intermittent Electrical stimulation (IES) is delivered to muscles at risk (i.e. gluteus maximus) through surface electrodes Muscle contractions are elicited every 10 minutes for 10 seconds; 12 hours per day

Patent pending

Electrodes and Stimulator

Stimulator Belt

Electrodes

Application

Smart-e-pants

Patent pending

SMART-E-PANTS FEASIBILITY STUDY

Objectives of Smart-e-Pants Feasibility Study:

1. Test Smart-e-Pants safety, stability, ease of use and acceptability by both caregivers and end-users

2. Evaluate feasibility of implementing Smart-e-Pants in: Acute care setting (Foothills Medical Centre, Calgary, AB) Rehabilitation hospital (Glenrose Rehabilitation Hospital,

Edmonton, AB) Long-term care facility (Allen Gray Continuing Care,

Edmonton, AB)

Time to Apply and Remove Electrodes vs. Smart-e-Pants

LTCF - ERH - ERH - GANR - EANR - G

Care Facility

Stability of Muscle Contraction

Care Facility

Care Facility

Skin Response to Electrodes

Patient Response to Smart-e-Pants

• Intermittent electrical stimulation may prevent pressure ulcers.

• Smart-e-Pants are an acceptable intervention for the prevention of pressure ulcers (for both caregivers and patients).

• While on the Smart-e-Pants protocol we have not had any patient developing pressure ulcers or other significant adverse events.

Conclusions

Next Steps

• Further enhancement of stimulator• Clinical testing in at-risk populations

Smart-e-Pants Team Calgary Sean Dukelow, MD Chester Ho, MD Robyn Warwaruk Rogers, RN

Dukelow Lab Jennifer Semrau, PhD Sonja Findlater, BSc OT

Acknowledgment

Smart-e-Pants Team EdmontonVivian Mushahwar. PhD

Ming Chan, MD

Richard Stein, PhD

Su Ling Chong, BSc, PT

Alisa Ahmetovic, BEng.

Ryan Somer, BSc OT

Dana Schnepf, RN BN

Glen Isaacson

Thank you!