Guidelines
FOR MEDICAL EXAMINERS, CORONERS AND PATHOLOGISTS: DETERMINING
INHALANT DEATHS
INTRODUCTION
Every year an untold number of individuals die as a result
of intentionally inhaling common, legal, everyday home, school
and office products. The National Inhalant Prevention Coalition
(NIPC) reports approximately 100 to 125 inhalant deaths per
year, based on contacts with families of victims and media
accounts. However this does not provide an accurate picture
of the full extent of this public health problem.
Inhalant abuse related fatalities are underreported
because they may not be recognized as such or because of a
perceived stigma. The National Inhalant Prevention Coalition
(NIPC) is providing background information and guidelines
to assist medical examiners, coroners, pathologists and toxicologists
to better understand, to recognize, to document and to accurately
report inhalant deaths.
Why is this needed?
* To better define the true scope of the problem;
* To track regional variations;
* To evaluate preventive interventions
* To evaluate treatment interventions
Background:
What are inhalants?
Inhalants are chemical vapors or gases that produce psychoactive
(mind-altering) effects when abused or misused by concentrating
and intentionally inhaling these fumes. These include volatile
organic solvents, fuel gases, nitrites, and anesthetic gases.
Inhalants are volatile organic chemicals. Volatility
is a measure of the tendency to vaporize or leave the liquid
state. The most common inhalant chemical groups are the aliphatic
and aromatic hydrocarbons, which are widely distributed in
nature, primarily in natural gas and petroleum. Examples include:
toluene, benzene, xylene and hexane. Another group of inhalants
is comprised of hydrocarbons with attached halogen ions. Examples
are trichloroethylene and the freons. Another group of inhalants
is anesthetic gases such as ether, nitrous oxide, chloroform
and halothane.
Once commonly referred to as "glue sniffing,"
inhalant abuse now includes a broad range of volatile solvents
and gas products (e.g. model airplane glue, paint thinner,
gasoline, and nail polish remover), aerosols (e.g. nonstick
cooking spray, computer keyboard cleaner and hair spray),
anesthetics (e.g., nitrous oxide or "laughing gas"
and ether), and nitrites (e.g. amyl, butyl, and isobutyl nitrites,
often marketed as "poppers" or room odorizers).
Other powdered drugs, such as heroin, cocaine, and methamphetamine,
can be inhaled but are not considered inhalants. Although
the chemicals involved and their effects vary, the route of
administration is the common factor
What Types of Products Can Be Abused?
* General Supplies—cements and glues; correction fluid;
magic markers;
solvent-based dry erase markers
* Cleaning Supplies—any product in an aerosol can; aerosol
air fresheners and deodorizers; computer air duster
* Wood Shop—paints; varnishes; stains; paint thinner;
contact cement
* Art Supplies—rubber cement; printing inks; spray paints
and clear finishes
* Auto—degreasers; spray lubricants; "Fix-a-Flat"
type products; solvents; Freon®; brake fluid; gasoline;
lacquers; lacquer; thinners
* Health and Beauty—nail polish and nail polish remover;
hair spray; deodorants
* Cooking Supplies—cooking spray; whipping cream in
aerosol cans; whipping cream cartridges (whippets)
What are the most common modes of administration?
Inhalants are abused either by "sniffing" though
the nose or inhaling fumes through the open mouth ("huffing")
much like a smoker inhales cigarette smoke. Usually the open
tube of glue, nail polish, or marker is placed close to the
nose and the fumes are inhaled.
People who abuse inhalants may also spray the
substance into a plastic or paper bag and huff that way ("bagging")
or even place the bag over their entire head.
Often a product will be poured or sprayed on
a piece of cloth, a rag, a towel, or a shirt sleeve or into
a soda can and inhaled in that manner.
Another method is to paint the fingernails with
a product like correction fluid and inhale the substance on
the nails.
Sometimes an aerosol substance is sprayed directly
into the mouth.
Substances can also be placed into alternative
containers (e.g., balloon filled with nitrous oxide) or heated
first and then inhaled
Who is likely to abuse inhalants?
Contrary to popular perception, people who abuse inhalants
are found in many segments of the population and no one group
can be categorized as
"inhalant abusers." In 2002, more than 22.8 million
Americans reported ever having used an inhalant, and about
180,000 were estimated to need treatment because they were
dependent on or abused inhalants. according to Substance Abuse
and Mental Health Services Administration’s (SAMHSA)
2002 National Survey on Drug Use and Health (NSHUH).
People who abuse inhalants are seen in emergency
rooms. According to the SAMHSA’s 2002 Emergency Department
Trends from the Drug Abuse Warning Network (DAWN), Final Estimates
1995 - 2002 report, which reflects reports from hospital emergency
departments, there were 1,496 inhalant related mentions. This
is an increase from 522 mentions in 2001 – a 186.6%
increase (however, inhalant mentions tend to fluctuate from
year to year).
Frequency:
According to the University of Michigan’s 2003 National
Monitoring the Future Survey, 11.2% of US high-school seniors
reported previous inhalant use. The US Substance Abuse and
Mental Health Administration’s 2002 National Survey
on Drug Use and Health reported over 22.8 million persons
had used inhalants, of which more than 2.6 million were between
the ages of 12 and 17.
Some studies indicate that inhalant abuse precedes
tobacco or alcohol use. Although most teenagers outgrow inhalant
use, many may progress to "harder" drugs in their
teens or even use them concurrently with inhalants. Some inhalant
abusers continue use into adulthood.
Unique risk groups for adults include nurses,
dentists, anesthesiologists, air conditioning repairers, shoemakers,
hair stylists, painters, and dry-cleaning workers, because
of access to these chemicals or anesthetics in the workplace.
Adults seek both the "high" offered by these agents,
plus the reportedly aphrodisiac effects. Nitrite inhalant
use is prevalent among homosexual males, but use has decreased
with the AIDS epidemic.
Internationally, inhalant abuse is rampant among
"street" children in many urban centers, in both
developed and developing countries, and represents a global
health issue.
Race:
These drugs have no social or geographic boundaries, but young
children who abuse inhalants tend to be of lower socioeconomic
class, poor school
performers with high rates of absenteeism or suspension, and
from broken
families.
* Inhalant abuse among children has been associated with higher
rates of
parental alcoholism and drug use. Users typically have low
self-esteem and emotional problems (anxiety, depression, and
anger).
* Inhalant abusers also have been associated with criminal
activity and tend to have more family members in prison than
non abusing children.
Though Caucasian children and adults are the
predominant abusers of inhalants, other racial groups at increased
risk include Hispanics and Native Americans. Most chronic
inhalant abuse is associated with poverty and deprivation
rather than race. Inhaling is frequently a group activity,
occurring at school or at parties.
Gender:
In the past inhalant abuse tended to be more prevalent in
males. However, over the past decade, abuse has increased
in young females, and prevalence is nearly equal today in
the youth population. Additionally, according to the 2002
NSDUH, girls begin inhalant use far earlier than boys with
a mean age of first use at 15.0 years, as compared to 16.3
years for boys. Among adults, inhalant abuse is more a male
activity.
Age:
The typical abusers of inhalants are 10-to-15-year-olds, though
use in children as young as 7 and 8 years has been reported.
Some studies indicate that the average age of initial use
of these chemicals is about 12. Experimentation typically
occurs in late childhood and is short lived.
Chronic abuse is usually seen in older adolescents,
though it has also been reported in individuals as old as
50 or 60.
Why are inhalants popular?
Most inhalants are readily available, inexpensive or free,
and usually legal to purchase and possess. The high is achieved
within seconds and the effect dissipates within a half of
an hour. Because products are easy to conceal and are useful
everyday products (e.g., permanent markers, correction fluid)
that are found in homes, offices, and schools, it is difficult
to prevent access to them. And, because abusable products
are so common, many youth do not perceive them as harmful
and do not understand the consequences of using them.
What do inhalants do?
Inhalants provide an instant "rush" and, like alcohol,
cause euphoria followed by central nervous system depression.
Deep breathing of the toxic vapors may result in losing touch
with one’s surroundings, a loss of self-control, violent
behavior, nausea, unconsciousness, giddiness, loss of inhibition,
loss of appetite, and, at higher doses, hallucinations. Inhalants
can cause loss of motor skills, slurred speech, heart palpitations,
seizures, nausea and vomiting. Signs of inhalant abuse include
"huffer’s rash" or drying and redness around
the mouth and nose, spots or sores around the mouth and red
or runny eyes or nose. However, these findings are very uncommon
even in chronic inhalant abusers. More common ones are paint
or stains on the body or clothing; chemical breath odor; drunk,
dazed, or dizzy appearance; an unexplained collection of abusable
products; anxiety, excitability, and irritability.
The debilitating and potentially lethal effects
of inhalants can occur even with first use. Sudden sniffing
death syndrome is usually caused by the irregular heart rate
induced by inhalants; other cardiac effects are hypertension,
tachycardia, and bradycardia. Other significant effects include
command seizures. Brain damage can be a consequence of chronic
use.
Additional inhalant dangers are suffocation
(e.g., from bagging), fire-related injuries from inhalant
combustion (especially if the inhalant is heated or a cigarette
is lit in a closed area where the inhalant is being abused),
and accidents related to impaired judgment, lack of motor
skills, or high-risk behavior.
What are the long-term effects of inhalant abuse?
Solvents are easily absorbed from the blood into lipid-rich
tissues.
Chronic inhalant abuse can damage the brain, the heart, lungs,
kidney, liver, and peripheral nerves.
Continued, chronic inhalant abuse has been associated
with neurological
damage. People who abuse inhalants chronically have demonstrated
a range
of mental dysfunction, from mild cognitive impairment (e.g.,
lack of
concentration or attention, poor memory, and poor learning
skills) to
severe. In some instances these effects are permanent while
in others they resolve after a long period of abstinence.
Personality disorders, particularly antisocial personality,
violent behavior, and depression, have been associated with
inhalant abuse.
Pathophysiology:
Inhalants are highly lipid soluble. They easily cross both
alveolar membranes and the blood-brain barrier. Exposure via
the pulmonary route avoids first-pass hepatic metabolism.
Onset of effect is seen in seconds. Volatiles accumulate in
the brain (as well as other fatty tissues in the body). The
mechanism of their effects is not entirely clear; some authors
suggest that the mechanism is "fluidization" or
change in solubility of neuronal cell membranes. The potency
of these drugs seems to be related to their solubility in
water. Other actions proposed include specific molecular ion
channels, whereby these chemicals would potentiate the effects
of GABA on the GABA-A receptors.
Inhaled concentration depends on the mode of
administration. Sniffing
offers the lowest concentration, while bagging the highest.
Huffing these chemicals produces an inhaled concentration
between that of sniffing and bagging.
These agents have a high volume of distribution
and several modes of elimination. With only a few important
exceptions, elimination occurs primarily through the lungs.
These exceptions include the alkyl nitrites, aromatics (like
benzene), and methylene chloride, which undergo significant
hepatic metabolism. In some instances, their metabolites can
be toxic with examples including free nitrites and carbon
monoxide.
Mortality/Morbidity
Inhalant abuse is associated with significant morbidity and
mortality rates. Use of inhalants can result in death. Bowen
reported 39 deaths in Virginia between 1987 and 1996 from
acute voluntary exposure to inhalants. Median age was 19 years
with 46% of the cases involving butane or propane. Maxwell
reported 144 deaths in Texas between 1988 and 1998 in which
use or abuse of inhalants was mentioned on the death certificates.
Median age was 24, and 35% of the cases involved chlorofluorocarbons
or Freon®.
CAUSES OF DEATH:
* Sudden Sniffing Death:
* Suffocation
* Trauma:
* Choking:
* Asphyxia:
INHALANT DEATH CONSIDERATIONS:
Inhalants should be considered as a cause of death where there
is a high index of suspicion of inhalant use from clinical
history and thorough scene investigation. This is especially
true if there is no apparent cause of death at the scene.
As this process continues it is very important that there
be proper specimen (autopsy) selection and collection for
analysis (provide toxicology laboratory with decedent’s
history to facilitate analysis). Ensure that there is a consistency
in reporting, at least within the same office and/or geographical
area.
A systematic approach is required to determine
that inhalants were a cause of death. Specifically:
* Investigation of circumstances;
* Death scene evaluation; and
* Sophisticated analytical toxicology.
SCENE INVESTIGATION:
The purpose of this is to ensure that all information pertinent
to determining the cause, manner and circumstances of a potential
inhalant fatality are considered in all investigations.
The death scene investigation is an essential
and critical component of a thorough investigation of a suspected
inhalant death. Information gathered during a thorough scene
investigation augments that obtained from an autopsy and a
clinical history review. The collection of specific products
at the death scene will help narrow and focus the toxicological
investigation and assist the pathologist, medical examiner
or coroner in ruling in or ruling out illicit inhalant use
as a cause of death.
The death scene investigation must include thorough
and systematic search of the area to determine whether there
were chemical or aerosol containers or canisters present or
in the vicinity of the incident. Likewise, a thorough investigation
should be made to determine if inhalant paraphernalia are
present (e.g. plastic bags, balloons, towels, soda cans with
paint stains, etc.). The victim’s face should be checked
for paint stains as well as their fingernails to determine
if a typewriter correction fluid type of substance is present.
CLINICAL CONSIDERATIONS:
History:
Inhalant abuse should be a consideration in any child, adolescent
or young adult who dies of inexplicable aspiration of his
or her gastric contents. It should also be a consideration
for traumatic deaths in this age group. Inhalants can be associated
with virtually any type of trauma including motor vehicle
crashes, falls, fire, suicide and violence.
However the commonest cause of inhalant abuse
death presents the greatest challenge. This is the sudden
sniffing death syndrome. The typical scenario is the victim,
while under the influence of an inhalant, is suddenly threatened,
(such as being discovered by an individual of authority) or
by a particularly frightening hallucination. The individual
begins to flee and suddenly collapses and dies at the scene.
The pathophysiology has been determined in experimental animals.
All inhalants are cardiac depressants. Inhalant induced bradycardia
predisposes to dysrhythmiae and the adrenalin surge associated
with the fight or flight response of a threatening situation
is the trigger for a fatal ventricular rhythm disturbance.
Autopsy findings are completely unremarkable and establishing
this diagnosis is dependent upon finding evidence of inhalants
in post-mortem blood specimens.
* The following tables are provided as additional
resources. Table 1
lists the chemicals commonly found in several commercial products
that
often are abused. Table 2 lists unique clinical effects of
several of
the major substances abused. (* Adapted from Miller and Gold,
1991)
Table 1. Chemicals Found in Specific Products
Product
|
Chemicals Found
|
| Balsa wood cement |
Ethyl acetate |
| Contact adhesives |
Toluene, hexane, esters |
| Cryoquick spray |
1,1,1 Tetrafluoroethane |
| Bicycle tire adhesive |
Toluene, xylenes |
| PVC cement |
Trichloroethylene |
| Air freshener, deodorants, fly spray, hair lacquer,
spray paints |
Halons, butane, dimethyl ether |
| Anesthetics/analgesics |
Nitrous oxide, ether, chloroform |
| Commercial dry cleaning |
1,1,1-Trichloroethane,
tetrachloroethylene, trichloroethylene |
| Fire extinguishers |
Bromochlorodifluoromethane,
halons 11 & 12 |
| Cigarette lighters/butane |
n-Butane, isobutane, propane |
| Propane |
Propane and butanes |
| Nail/varnish remover |
Acetone and esters |
| Paints/paint thinners |
Butanone, esters, hexane, toluene, xylene |
| Paint stripper |
Dichloromethane, toluene |
| Surgical plaster/chewing gum removers |
Trichloroethylene |
| Typewriter correction fluid/ paint thinners |
1,1,1-Trichloroethane |
Table 2. Unique Clinical Effects of Several
Volatile Substances
| Chemical |
Unique Effects |
| Benzene |
Hepatorenal toxicity, leukemia |
| Toluene |
Muscle weakness, GI symptoms,
renal tubular acidosis |
| Hexane |
Stocking-glove peripheral neuropathy |
| Xylene |
Encephalopathy, hepatorenal toxicity |
| Carbon tetrachloride |
Sudden death, arrhythmias |
| Gasoline |
Organic lead encephalopathy |
| Nitrites |
Methemoglobinemia, hypotension |
| Nitrous oxide |
Vitamin B-12 deficiency, neuropathy |
POSTMORTUM EXAMINATION:
EXTERNAL:
Skin
* Paint or stains on the face, hands, or clothing
* "Huffer rash" - Erythematous “frost bite”
eruption on the face and
oral mucosa
* Thermal or chemical burns on face or hands
* Conjunctival injection
* Cyanosis (suspect methemoglobinemia)
INTERNAL:
* Oral/airway burns
* Frostbite injury of the airway is associated with chlorofluorocarbons
found
in air conditioners
COLLECTION OF TOXICOLOGIC SAMPLES:
Laboratory:
* Serum chemistry: Analyses may include a standard panel including
sodium, potassium, chloride, bicarbonate, BUN, and creatinine.
Some of the inhalants, toluene in particular, cause a syndrome
of distal renal tubular acidosis, with a resultant elevated
anion gap, hyperchloremia, hypokalemia, and hypophosphatemia.
Hypoglycemia may be noted.
* Serum levels: Serum drug levels may be helpful if the specific
chemical involved is known and if the laboratory has the ability
to measure these levels
Specific lab tests may be indicated for the
following volatiles:
* Methylene chloride: Check carboxyhemoglobin level, use 100%
nonrebreather oxygen
* Alkyl nitrites: Check serum methemoglobin levels. effect.
* Carbon tetrachloride: Consider hepatic injury and necrosis.
TISSUE AND FLUID SPECIMAN SAMPLING:
| TISSUE OR FLUID |
SAMPLE |
| Brain |
500 g. or whole organ after histologic sampling: frontal
lobes usually least import for neuropathologist |
| Liver |
500 g. or whole organ after histologic sampling |
| Lung |
One lung or each lung separately after histologic
sampling |
| Kidneys |
Each kidney separately after histolgic sampling |
| Stomach |
Entire with contents or contents separately; vomitus
if available |
| Intestine |
Separately tied portions of intestinal tract with contents |
| Cerebrospinal fluid |
As much as can be withdrawn |
| Heart blood |
100 ml with preservative and 100 ml without
preservative |
| Peripheral blood |
30 ml. using anaerobic technique to avoid evaporation
of volatile substances |
| Bile |
All |
| Urine |
All |
| Muscle |
200 g aliquots |
| Fat |
200 g aliquots |
| Hair |
10 g |
| Fingernails |
10 g |
| Vitreous humor |
2 to 3 ml from each eye |
Note: Specimens should be refrigerated or frozen.
Specific toxicologic analysis for inhalants typically requires
a specialized reference laboratory.
CONCLUSION:
The determination of the extent and the scope of inhalant
abuse will remain problematic without appropriate procedures
and protocols to determine whether or not an inhalant death
has occurred. These guidelines provide a framework for this
to be done.
