Electrical Stimulation Eases Asthma Attack
Electrical Stimulation May Be a Safe Option for Treating Severe Asthma Flare-Ups
Nov. 3, 2009 -- Here’s a shocking way to help asthma patients catch their
breath during a sudden and severe attack: Deliver tiny electrical impulses
under the skin in the neck.
Researchers from five U.S. institutions have found that electrical
stimulation can safely be used to open the airways during an acute asthma
attack when traditional medications do not work. According to the American Lung
Association, about 23 million Americans are living with asthma.
The small study involved four conscious and responsive adults aged 26 to 58
who visited a hospital emergency room during a moderate-to-severe asthma attack
and whose symptoms did not improve after using inhalers and powerful
anti-inflammatory (steroid) medications. Such treatments were considered a
failure if the patient scored 70% or less on a lung function test that measured
how much air could be forced out of the lungs after taking a deep breath. This
is called force expiratory volume, or FEV. The amount of air forced out in the
first second is known as FEV1.
The electrical stimulation technique is a minimally invasive procedure that
is done while the patient is awake. Anesthesia is applied to the neck, and then
the doctor inserts an electrode under the skin into the tissue surrounding the
carotid artery and vagus nerve. Live ultrasound images are used to help guide
The study participants received mild but continuous electrical pulses for
three hours, ranging from 1-12 volts. The voltage was increased until symptoms
improved or the stimulation triggered muscle twitching or discomfort.
Researchers compared breathing measurements taken before the stimulation to
those obtained every 30 minutes during the procedure and after the stimulation
A half-hour into the treatment, the patients could blow more air out of
their lungs after taking a deep breath. Their FEV1 scores remained increased
for 30 minutes after treatment.
The study team says electrical stimulation may provide a drug-free and
non-airflow-dependent method of opening the airways in critical asthma attack
situations. They will announce their findings in San Diego this week at CHEST
2009, a meeting of the American College of Chest Physicians.