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ASPIRATION:

RISKS,

RECOGNITION,

AND

PREVENTION

DANA BARTLETT, RN, BSN, MSN, MA

Dana Bartlett is a professional nurse and author. His clinical experience includes 16

years of ICU and ER experience and over 20 years of as a poison control center

information specialist. Dana has published numerous CE and journal articles, written

NCLEX material, written textbook chapters, and done editing and reviewing for

publishers such as Elsevire, Lippincott, and Thieme. He has written widely on the

subject of toxicology and was recently named a contributing editor, toxicology

section, for Critical Care Nurse journal. He is currently employed at the Connecticut

Poison Control Center and is actively involved in lecturing and mentoring nurses,

emergency medical residents and pharmacy students.

ABSTRACT

Both national safety and health facility protocol guide nursing practice

in the area of aspiration risk precaution and treatment. Multiple factors

influence the potential for aspiration risk and complications stemming

from silent and major aspiration episodes. Nursing interventions in

acute care and long-term settings involve recognizing the potential for

aspiration and implementing preventive and timely treatment

measures when an issue of aspiration occurs, such as aspiration

pneumonia and its sequela.


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Continuing Nursing Education Course Planners

William A. Cook, PhD, Director, Douglas Lawrence, MA, Webmaster,

Susan DePasquale, MSN, FPMHNP-BC, Lead Nurse Planner

Policy Statement

This activity has been planned and implemented in accordance with

the policies of NurseCe4Less.com and the continuing nursing education

requirements of the American Nurses Credentialing Center's

Commission on Accreditation for registered nurses. It is the policy of

NurseCe4Less.com to ensure objectivity, transparency, and best

practice in clinical education for all continuing nursing education (CNE)

activities.

Continuing Education Credit Designation

This educational activity is credited for 2.5 hours. Nurses may only

claim credit commensurate with the credit awarded for completion of

this course activity.

Statement of Learning Need

Risk factors for aspiration are a national safety concern in acute care

and long-term care facilities. Nurses provide the primary care for

patients at the bedside where the use of screening tools and protocol

to recognize patient risk and an aspiration event is most crucial.

Although aspiration can often be a benign event, the risk of aspiration

in elderly and acutely ill patients, such as those with mental status


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changes, poses a severe health concern with significant morbidity and

mortality if standards of care are not appropriately observed.

Course Purpose

To provide knowledge about aspiration risk, prevention and treatment

in acute care and long-term care settings.

Continuing Nursing Education (CNE) Target Audience

Advanced Practice Registered Nurses and Registered Nurses

(Interdisciplinary Health Team Members, including Vocational Nurses

and Medical Assistants may obtain a Certificate of Completion)

Course Author & Planning Team Conflict of Interest Disclosures

Dana Bartlett, RN, BSN, MSN, MA, William S. Cook, PhD,

Douglas Lawrence, MA, Susan DePasquale, MSN, FPMHNP-BC -all have

no disclosures

Acknowledgement of Commercial Support

There is no commercial support for this course.

Activity Review Information

Reviewed by Susan DePasquale, MSN, FPMHNP-BC

Release Date: 4/29/2016 Termination Date: 4/29/2019


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Please take time to complete a self-assessment of knowledge, on page 4, sample questions before reading the article.

Opportunity to complete a self-assessment of knowledge learned will be provided at the end of the course.

1. Aspiration is defined as

a. infection of the lungs from nasal secretions. b. movement of a foreign substance into the lungs.

c. abnormal or difficult swallowing. d. the absence of a gag reflex.

2. The most important protection against aspiration is the

a. epigastric reflex.

b. nasal reflex. c. gag reflex.

d. Babinski reflex.

3. Which of these prevents foreign objects from entering the

larynx?

a. The uvula b. The pharynx

c. The esophageal sphincter d. The epiglottis

4. True or False: Approximately 30% of people do NOT have a

functioning gag reflex.

a. True b. False

5. Which of the following are common causes of aspiration?

a. Myocardial infarction and hypertension

b. Diabetes and Alzheimer’s disease c. Stroke and dysphagia

d. Irritable bowel syndrome and general anesthesia


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Introduction

Aspiration is defined as the movement of a foreign substance into the

lungs. Aspiration is very common and it can cause significant and

serious complications. All nurses working in acute and long-term care

settings need to be able to recognize factors that increase the risk for

aspiration, know which patients are most likely to aspirate, and to

understand the signs and symptoms of aspiration. These are essential

aspects of safe and appropriate nursing care to avoid an adverse

patient event.

Swallowing And The Gag Reflex

Aspiration is intimately related to swallowing and the gag reflex so to

understand aspiration the nurse must be familiar with these normal

physiological functions. The cough reflex is also involved in aspiration

and that will be discussed briefly in another section of this learning

module.

Upper Gastrointestinal Tract and Associated Structures

Swallowing is the coordinated movement of food or liquids from the

mouth to the stomach. It will be explained here in terms of swallowing

solid food but the process is essentially the same for liquids.

Swallowing can best be understood by dividing it into two phases:

voluntary and involuntary. These will be discussed in context of the


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upper gastrointestinal tract structures known to be involved during the

process of swallowing.1 Finally, aspiration prevention will be reviewed.

The Gastrointestinal Tract

The gastrointestinal tract starts with the mouth, which is also called

the oral cavity. It then descends into the pharynx, esophagus and into

the stomach as depicted in the following table.1

Table 1: The Upper Gastrointestinal Tract

Oral Cavity ↓

Pharynx ↓

Esophagus ↓

Stomach

The sections of the upper gastrointestinal tract are described in

greater detail in the following section.1

Oral Cavity

The oral cavity is the beginning of both the respiratory tract and the

gastrointestinal tract. In terms of swallowing the primary function of

the oral cavity is to begin the digestion of food and to break down food

into manageable sizes.

Pharynx


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The next section of the gastrointestinal tract is the pharynx, a

relatively short tube made of muscle and connective tissue that is

located behind the larynx. The pharynx connects the oral cavity to the

esophagus. The pharynx is further comprised of the nasopharynx, the

oropharynx, and the laryngopharynx. The primary functions of the

pharynx are to allow passage of food and liquid into the esophagus

and air into the trachea.

Esophagus

The esophagus is a thick-walled tube of muscle and cartilage that is

located behind the larynx and the trachea. The esophagus connects

the pharynx to the stomach and like the pharynx, its primary function

is to allow for the passage of food and liquids. The esophagus has two

sphincters, the upper and lower esophageal sphincters. A sphincter is

a ring of muscle that can open and close and there are many

sphincters throughout the body; the anal sphincter is an example.

The upper esophageal sphincter is located at the junction of the

pharynx, and the lower esophageal sphincter is located at the juncture

of the esophagus, where it meets the stomach to complete the

passage of food or fluids. The esophageal sphincters are not under

voluntary control and except during swallowing, they are normally

closed.

Gastrointestinal Tract and Associated Structures

The associated structures to the upper gastrointestinal tract are

described below in greater detail.

Epiglottis


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The epiglottis is a flap of cartilage that is attached to the upper part of

the larynx. One end of the epiglottis is attached to the larynx (this

attachment can be thought of as a hinge) and the other end projects

backwards up and behind the tongue. The epiglottis has a vital role in

normal swallowing and the prevention of aspiration, and this will be

discussed later on in this module. The epiglottis is above the glottis,

which is the opening between the vocal cords.

Larynx

The larynx is the initial section of the respiratory tract. It is a short

tube of muscle and cartilage that begins in the oral cavity and

connects to the trachea (commonly known as the windpipe). The

larynx is relevant to this module because the larynx is where coughing

is initiated and coughing is an important protective reflex that keeps

foreign bodies from entering the lungs.

Swallowing

As mentioned above, swallowing can best be understood by dividing it

into two phases: voluntary and involuntary, which are explained

further here.

Voluntary Phase

Swallowing is for the most part an automatic process; we do not have

to think about swallowing as it happens. However, the initial phase of

preparing the food for swallowing and the beginning of swallowing is

under voluntary control.


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The voluntary phase (also called the oropharyngeal phase) of

swallowing begins in the oral cavity by lubrication of the food with

saliva and digestive juices and chewing the food into small pieces that

can pass through the upper parts of the gastrointestinal tract; these

small pieces of food are called boluses.

Involuntary Phase

After food has been chewed and lubricated, the lips close to seal the

mouth and the tongue moves the bolus to the back of the oral cavity

and into the oropharynx. At this point the involuntary phase (also

called the esophageal phase) of swallowing begins.

As the food bolus or liquid reaches the oropharynx a series of

coordinated movements begin to push the food or liquid smoothly

through the upper gastrointestinal tract and into the stomach. When

examined closely, this process has many steps but it can be explained

quite simply. Although the swallowing process is presented here step-

by-step, all of these actions happen essentially at the same time.

Table 2: The Process of Swallowing

1. The pressure of the food bolus in the pharynx causes the

muscles of the pharynx to contract and to move the food away

from the mouth and into the pharynx.

2. The uvula contracts and covers the opening of the

nasopharynx, preventing food from entering the nasal

passages.


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3. Laryngeal movement: Once the food bolus or liquid reaches

the back of the oral cavity, the larynx moves upward. This

helps close the glottis and prevents food from passing

through the vocal cord and into the trachea.

4. Epiglottis movement: At the same time that the larynx is

moving upward to close the glottis, the epiglottis swings

down and covers the opening of the larynx, acting like a

cover. This prevents food or liquid from entering the trachea.

5. Sphincter relaxation: The esophageal sphincter relaxes,

providing access to the esophagus.

6. Peristaltic action: Once the food or liquid enters the

esophagus it is moved along by involuntary rhythmic muscles

actions called peristalsis.

Because the esophagus is essentially a closed tube, pressure

on any part of the esophagus will move food or liquid in the

direction of least resistance - in this case, towards the lower

esophageal sphincter and the stomach. A useful way to think

of this is to imagine squeezing an open tube of toothpaste;

when you do so the contents will be moved out through the

opening and peristaltic contractions in the esophagus function

in the same way.

7. The lower esophageal sphincter relaxes and allows for

passage of the food bolus or liquid into the stomach.


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During the process of swallowing, other physiological actions that

involve the oral cavity, the pharynx, the larynx, or the esophagus

cannot be done. When a person is swallowing he or she cannot inhale,

exhale, talk, vomit, or cough.

When the process of swallowing is reviewed, two things are prominent

and have particular relevance to the topic of aspiration.

1. The gastrointestinal tract and the respiratory tract are in close

proximity; at certain points there is very little that separates them.

2. Swallowing requires the coordinated action of many muscles,

nerves, and reflexes; it is a relatively complicated act.

Given these two points, it becomes apparent that there is considerable

potential for food or liquid to be aspirated, and that there are many

steps in the process of swallowing that can break down and put a

patient at risk of aspiration.

Gag Reflex And Cough Reflex

The gag reflex and the cough reflex protect the lungs from aspiration

and entry of foreign objects. The gag reflex involves the oral cavity

and the upper part of the gastrointestinal tract; the cough reflex

involves the upper part of the respiratory tract. The gag reflex, which

is more formally called the pharyngeal reflex, is the most important

protective mechanism for the prevention of aspiration and it will be

discussed in detail here.1

The gag reflex occurs when a foreign object touches the roof of the

mouth, the back of the tongue, the areas around the tonsils or the


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uvula, or the oropharynx. When a person swallows, food and liquids

contact these areas but the automatic closing of the epiglottis prevents

aspiration from occurring. This protective mechanism is absent during

a potential aspiration situation but the gag reflex takes over and stops

foreign objects from entering the lungs.

Nerve endings located in the roof of the mouth, the back of the

tongue, etc., are stimulated by the physical contact with food or fluid

and this stimulation initiates very strong, forceful contractions of the

pharynx, which expels the foreign object. The patient experiences the

gag reflex as coughing, choking, and gagging.

Learning Break:

An easy way to imagine the gag reflex is to think about an

experience we have all had, one that is commonly called “having

something go down the wrong way.” A piece of food or some liquid

reaches the back of your mouth and you begin to gag and cough.

An intact functioning gag reflex is essential to prevent aspiration.

However, it has been estimated that the gag reflex is absent in almost

30% of the population and some people may have a gag reflex but it is

not very strong. In addition, there are many diseases and medical

conditions that can temporarily or permanently damage the gag reflex,

making that person susceptible to aspiration. The cough reflex is also

important for preventing aspiration. The primary function of the larynx

and trachea is to move air into the lungs and the respiratory tract and

any foreign substance that enters the airways interferes with

respiration and is a potential cause of infection. Nerve endings located


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on the larynx and the trachea becomes stimulated when a foreign

body enters the larynx or trachea. A forceful cough is produced, which

aids the foreign object to be expelled.

Aspiration: Causes, Signs, Symptoms, Consequences

Aspiration occurs when the gag reflex and the cough reflex fail to

prevent a foreign substance from entering the lungs. The common

conception of aspiration is that it is an abnormal and dramatic

pathologic event that causes coughing, choking, and a serious

complication such as pneumonia. This is certainly true for some

aspiration events but aspiration is actually a common occurrence and

it may not result in harm.

Studies have shown that at least one-half of all adults aspirate during

sleep and the aspiration does not wake them up or cause signs or

symptoms. Aspiration happens to normal, healthy adults who have a

functioning gag reflex. They aspirate very small amounts of saliva,

mucous, and possibly gastric juices. The aspirations that result in

serious harm occur in a very different population, under very different

circumstances, and with potentially serious consequences. Why and

how these aspirations become harmful are highlighted below.3,4,7,8

Volume

In patients who may suffer a harmful aspiration there is often a large

volume that enters the lungs. An example of this would be the patient

who has aspirated tube feedings. A milliliter or two would be tolerated

but 30 ml or more, for example, would cause signs and symptoms.

However, serious aspiration can occur from a small volume or amount.


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Substance

If the aspirate contains infectious bacteria the patient may develop

aspiration pneumonia.

Frequency

Aspirations occurring repeatedly expose the respiratory tract/lungs to

more frequent stress and the patient has less time to recover.

Patient Issues

There are many individual factors that influence how often aspirations

occur and whether such events cause complications. For example,

patients with a decreased level of consciousness, compromised

immune system, or a respiratory illness, i.e., pneumonia or chronic

obstructive pulmonary disease (COPD) that decreases the blood

oxygen level. In all of these situations, aspiration and/or harm from

aspiration is more likely to occur. There are many causes of aspiration,

as shown in Table 3 below; however, this list is not all-inclusive.

Table 3: Causes of Aspiration

Cerebral vascular accident (Stroke)

Drug or alcohol overdose

Dysphagia

Excessive production of oral secretions

General anesthesia

Grand mal seizure

Mechanical ventilation

Nasogastric feedings


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Neurologic diseases

Prolonged vomiting

Sedative, hypnotic, or opioid medications

Tracheostomy

Traumatic brain injury

In addition to the above list of identified causes of aspiration being not

all-inclusive, there is also some overlap; for example, many people

who have a stroke develop dysphagia. This list can certainly be studied

and referred back to from time-to-time, however, it is more useful to

view these causes of aspiration as having similarities. Understanding

these similarities will help to identify patients who are at risk for

aspiration. These similarities are elucidated below.

The patient has a depressed level of consciousness. Someone who

has a depressed level of consciousness often has a weak or absent

gag reflex. Often, in such a scenario the patient is described as

someone not having the ability to “protect the airway.” This can

happen to a patient who has had a stroke, experienced a seizure,

or following a drug overdose.

Protective reflexes are absent or compromised. Examples of this

would include a patient who 1) has been endotracheally intubated

or who has a tracheostomy, 2) had placement of a nasogastric

feeding tube, or 3) has dysphagia. (Dysphagia will be discussed

later in the module).

Experienced nurses know that when patients have a depressed level of

consciousness there is also a loss of protective reflexes; the two


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frequently go together. For example, a patient who has had a stroke

may be comatose and have a damaged gag reflex.6

Learning Break:

Dysphagia is a medical term that means difficulty in swallowing.

Common neurological problems such as Alzheimer’s disease,

stroke, and traumatic brain injury frequently cause dysphagia and

dysphagia is a significant risk factor for aspiration. Dysphagia is

very common; the authors of a recent article in the medical journal

Chest noted that dysphagia is present in at least 30% of all

hospitalized patients. Unfortunately, dysphagia often goes

unrecognized.

Aspiration Signs And Symptoms

The signs and symptoms of aspiration can be subtle and very clear or

some patients can aspirate and initially be asymptomatic. The obvious

signs and symptoms of aspiration are coughing, choking, and difficulty

breathing and they often occur after a situation that puts the patient

at risk. For example, a patient who recently had a stroke and is taking

fluids by mouth for the first time begins to cough and gasp.

Experienced nurses recognize this as a situation with the potential for

aspiration risk and of course coughing and gasping cannot be missed.


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It is difficult to recognize aspiration when aspiration is slight, if the

signs and symptoms are minor, or if the patient is initially

asymptomatic.12 In these situations the nurse must remember who is

at risk for aspiration and be on the alert for clues that an aspiration

has happened. Signs and symptoms of aspiration are listed in Table 4

below.

Table 4: Signs and Symptoms of Aspiration

Change in consciousness, especially depressed consciousness

Decreased oxygen saturation as measured by pulse oximetry

Excessive drooling

Fatigue

Fever

Increased sputum production

Persistent, mild cough

Rapid breathing

Tachycardia

Vomiting soon after meals

Of course, signs and symptoms of aspiration listed above are non-

specific. There are many reasons why a patient may have a fever or a

rapid pulse. If these signs are present in a patient who has risk factors

for aspiration, then the possibility should be investigated.

Learning Break:

Asymptomatic aspiration is also called silent aspiration, and it is


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especially worrisome. It cannot be detected without specialized

testing, and patients who have silent aspirations are much more

likely to develop aspiration pneumonia. Silent aspirations are not

rare. One study found that 25% of all patients who had a confirmed,

documented aspiration had experienced a silent aspiration.

The Consequences Of Aspiration

Aspiration can cause airway obstruction and interfere with ventilation.

It can also cause an inflammation of the lungs called chemical

pneumonitis, aspiration pneumonia, or a combination of these

conditions. This section discusses known risks and complications of

aspiration.10,11,12

Aspiration pneumonia is perhaps the most common complication of

aspiration. It occurs when a patient aspirates bacteria or other

microorganisms from his or her oral cavity, nasal passages, or upper

stomach. These microorganisms are part of the normal flora of the

upper respiratory tract and the gastrointestinal tract, but if they enter

the lungs they can multiply and then are not benign. Aspiration

pneumonia can develop if these oral, nasal, or gastric nasal secretions

contain a large number of microorganisms, if the aspirations are

frequent, or if the patient is susceptible to a respiratory infection.

It is important to remember that the size of the aspiration is not

important. Aspiration pneumonia can occur even after a very small

aspiration, and aspirations can be silent. Just as importantly, nurses

should be aware that pneumonia occurs in approximately one-third of

all patients who aspirate. The exact incidence of aspiration pneumonia


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is not known but it is a relatively common problem. It is especially

prevalent in the elderly population; quite commonly in the elderly who

have dysphagia and in elderly people who are hospitalized. For elderly

who are hospitalized, aspiration pneumonia is also very dangerous.

One study found the mortality rate of hospital-associated aspiration

pneumonia to be almost thirty percent.

The signs and symptoms of aspiration pneumonia vary considerably

and depend on how recently the aspiration happened, the patient’s

basic state of health, and the virulence of the microorganism. Common

clinical problems that are seen are drowsiness, fever, rapid breathing,

and tachycardia. If the patient is elderly and dehydrated, he or she

may be hypotensive, as well. It is also possible for the patient to have

relatively mild signs and symptoms for a few days as the aspiration

pneumonia develops.

Aspiration pneumonia is diagnosed by examining the patient, by

recognizing risk factors for aspiration, and most definitively by chest

x-ray. Laboratory studies, including culture of sputum have limited

usefulness in diagnosing aspiration pneumonia. Aspiration pneumonia

is treated with antibiotics and fluids.

Prevention Of Aspiration

As with any medical problem, disease prevention is far better than

treatment. Aspiration prevention is considered to be a key component

of safe and appropriate healthcare, and it involves identifying patients

who are at risk and then using practical methods to ensure that

patients do not aspirate.10,11,12


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Identifying Risk for Aspiration: Screening Methods

Aspiration prevention is considered to be a key component of good

healthcare. The Agency for Healthcare Research and Quality (AHRQ) is

an agency of the National Institutes of Health, and the AHRQ

recommends as one of its 30 Safe Practices for Better Health Care that

all patients be screened for aspiration. To quote the AHRQ: “Upon

admission, and regularly thereafter, evaluate each patient for the risk

of aspiration.”2 Evaluating stroke patients within 24 hours of admission

for their risk of aspiration and the presence of dysphagia is also

typically recommended.

Prevention of aspiration begins with recognizing patients who are at

risk for this problem and this has been shown to be both simple and

difficult. The simple part is identifying which patients are likely to

suffer an aspiration (as covered earlier on in this learning module). If

the answer is Yes to any of the screening questions highlighted in the

table below then the patient is at risk for aspiration.

Table 5: Basic Screening for Aspiration Risk

Is the patient elderly?

Is she or he receiving any medications that can cause sedation?

Does the patient have a neurological disease or disorder?

Does the patient have excess secretions?

Was general anesthesia recently used?

Does the patient have obvious difficulty eating/swallowing?

Is he or she unable to sit upright?

Has the patient has a prior aspiration?

Does she or he have a history of dysphagia?

Does the patient have a depressed level of consciousness?


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This basic assessment should be done for all patients, and for patients

who are especially susceptible to aspiration it should be repeated from

time to time. Most healthcare facilities will have an aspiration

screening tool and a protocol for how and when to use it. There are

bedside and technical-based screening methods that can be used for

detecting aspiration, evaluating aspiration risk, and for detecting one

of its most common causes, dysphagia. Unfortunately, there is no

universal agreement as to which one is best and when they should be

used and that is the part of aspiration and dysphagia screening that is

difficult. Explaining all of these screening methods is beyond the scope

of this learning module but commonly used ones are listed in Table 6.

The EAT-10 can be done at the bedside without specialized equipment

and is briefly discussed here.

Table 6: Screening Methods for Detecting Aspiration/Dysphagia

Barium swallow test

EAT-10

Endoscopy

Video-fluoroscopic evaluation (VSE)

Water swallow test

All of the screening methods listed in Table 6 (except the EAT-10) are

technical tests while the EAT-10 is a questionnaire that can be used to

determine the need for more complicated screening. The EAT-10 asks

the patient to respond to these 10 statements.

Table 7: The EAT-10 Questionnaire

1. My swallowing problem has caused me to lose weight.


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2. My swallowing problem interferes with my ability to go out for meals.

3. Swallowing liquids takes extra effort.

4. Swallowing solids takes extra effort.

5. Swallowing pills takes extra effort.

6. Swallowing is painful.

7. The pleasure of eating is affected by my swallowing.

8. When I swallow food sticks in my throat.

9. I cough when I eat.

10. Swallowing is stressful.

The answers to the questions are scored on a scale from 0 – 4 (0 = no

problem to 4 = severe), and if the total score is 3 or higher the patient

may have a swallowing problem and more aggressive evaluation

should be considered.

Practical Methods For Aspiration Prevention

If a patient has been identified as being at risk for aspiration or if the

patient has aspirated, then practical methods designed to prevent this

from happening should be started. Basic steps to prevent aspiration

are reviewed are highlighted here.14,15 The first step nurses should

follow is to use the aspiration evaluation protocol that their healthcare

facility has adopted. Nurses should also keep in mind the screening

questions that are listed above. Specific measures for preventing

aspiration include: 1) patient positioning, 2) oral care; 3) assessment

of nasogastric tube placement; 4) tube feeding technique;

5) measuring residual gastric volume; and, 6) avoiding the use of

sedating drugs.

Each healthcare facility will use these preventive measures in a

different way and some of them may not be used at all, so it is not

possible to provide strict, definitive guidelines for their use. Nurses


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should follow the protocols established for their workplace and when in

doubt they should review facility protocols with a nursing supervisor.

Nurses are also key agents in their workplaces to advocate for best

practice protocols and improved standards of safe and appropriate

practice relative to aspiration risk precaution. The following patient

care interventions are recommended practice to prevent aspiration in

acute care and long-term care health facilities.

Positioning

Elevating the head of the bed is a very effective method for preventing

aspiration. Lying flat or with the head slightly elevated increases the

possibility of aspirating, especially so if a patient has an absent or

weak gag reflex or is receiving feedings by a nasogastric tube. Keep in

mind that one of the first things people do when food or liquid “goes

down the wrong way” is to stand up. Elevating the head of the bed at

30°-45° for patient safety is typically recommended, however the

exact degree to which the head of the bed should be elevated is also

generally determined by health facility protocol.10

Oral Care

Entry of oral, nasal, and gastric secretions into the lungs cause

aspiration pneumonia. Rigorous attention to oral care and possibly the

use of antiseptic mouth rinses that contain chlorhexidine are often

used as ways to reduce the number of microorganisms in the oral

cavity and prevent aspiration pneumonia. Chlorhexidine is an

antibacterial agent and a 0.12%-0.2% solution can be applied to a

sponge to swab the patient’s mouth four times a day. The frequency of


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chlorhexidine use and the protocol may vary from hospital to

hospital.13,16

Assessment of Nasogastric Tube Placement

Nasogastric tubes can easily become misplaced, putting the patient at

risk for aspiration. Frequent assessment of the proper position of

nasogastric tube placement is a responsibility of the nurses in terms of

preventative technique and long-term management. The management

of tube feeding and aspects of the nursing assessment to prevent

aspiration are reviewed below.5,6,9

Tube Feeding Technique

If a patient is receiving tube feedings and is at risk for aspiration, tube

feedings should be given at the prescribed rate. The nurse should not

increase the tube-feeding rate unless there is a specific order to do so

and should never administer a tube feeding as a bolus. Bolus feeding

increases the risk for aspiration.

Measuring Residual Gastric Volume

A technique that has traditionally been used to prevent aspiration in

patients who are receiving nasogastric feedings is measuring residual

gastric volume. After a tube feeding, the amount of enteral nutrition

liquid that is still in the stomach is measured. If the residual is above a

certain amount then it is assumed that the patient’s gastrointestinal

tract is not properly absorbing the liquid nutrition and the excess

volume puts the patient at risk for aspirating. This technique may be

helpful for certain patients but recent research has questioned its

usefulness.


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Avoid Sedating Drugs

The use of sedating drugs increases the risk of aspiration.

Administering these medications is a nursing responsibility.

Additionally, the nurse should be assessing patients for excessive

drowsiness caused by sedatives, analgesics, and other drugs that can

cause central nervous system depression and reporting these adverse

effects if they occur to the patient’s primary medical provider.

Case Scenario: Aspiration Pneumonia

Mrs. B is an 86-year-old female who has just been discharged from the

hospital and admitted to a long-term care facility. She recently suffered a

stroke that left her with significant weakness of her left arm and leg. She is

unable to walk but with some assistance she can perform some simple

activities of daily living and her mental status and speech are completely

intact.

The patient has been depressed and occasionally mildly agitated as she

tries to adjust to her limitations. In addition her appetite has been poor

and for the past two days she has refused to eat, telling the staff that food

“makes me sick.” She also complains of persistent pain in her left side.

Because of these developments the physician ordered the patient to be

given a low dose of fluoxetine, a commonly used anti-depressant.

The physician also requested an orthopedic and physical therapy consult

and while awaiting the results of those evaluations, she prescribed a non-

narcotic analgesic, tramadol.

Finally, after extensive discussions with the patient and with her

acceptance, a small nasogastric tube was inserted and enteral tube

feedings were begun. It was understood that the feeding tube would be in


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place for only a short period of time. Several days after the fluoxetine,

tramadol, and tube feedings were started the patient’s condition was

improved. Her mood was brighter, her pain was decreased, and she

seemed to have more energy. Mrs. B’s pain was diagnosed as

osteoarthritis, she was able to start physical therapy.

Plans were made for to move Mrs. B (within a few weeks) to a relative’s

house, albeit with the support of visiting nurses. However, after a week of

clinical gains the staff began to notice some mild regressions.

The patient was sleeping more and had less energy during the day,

although there were periods of time in which she seemed normal. She also

had a fever of 100.1° F, but this only occurred once and the fever

responded to fluids and a dose of acetaminophen.

On the seventh day of her tube feedings, Mrs. B was noted to have a fever

of 102.7° F and her respiratory rate was 24. Shortly after being assisted

from her bed to a chair, Mrs. B had several forceful, productive coughs and

the nurse saw undigested tube feeding residue in the patient’s sputum. The

physician was notified, a chest x-ray was done, and it was clear that Mrs. B

had aspirated and had pneumonia.

In the above scenario, the patient had obvious risk factors for an

aspiration. She had recently had a stroke, was prescribed several

medications that are known to cause central nervous system

depression, a nasogastric tube was in place, and she was receiving

enteral tube feedings. The clinical course the patient experienced was

fairly typical, with some subtle signs of silent aspiration being present

before it became clear that some of the tube feeding and gastric juices

had entered her lungs.


27

Summary

Episodes of aspiration can be sudden and dramatic, but aspirations can

also be very minor and the patient may remain asymptomatic, the so-

called silent aspiration. The causes of aspiration are many, and some

of the common ones have been reviewed here. Although the causes of

aspiration are all distinct, separate problems they share two common

characteristics: the patient is likely to have a depressed level of

consciousness and the protective mechanisms that prevent aspiration

are absent or compromised. Dysphagia in particular is very common

and a significant cause of aspiration.

Aspirations can cause serious medical problems, especially if there is a

large volume that has been aspirated and when the aspirate contains a

large number of infectious bacteria. When aspirations occur repeatedly

the patient is more predisposed to pulmonary complications. Nurses

need to be informed of the most common complication of aspiration -

aspiration pneumonia - as well as protocol to prevent its occurrence,

common signs and symptoms, and treatment. Screening for aspiration

is a vital part of care that every nurse working in acute and long-term

care facilities should implement in their work settings. Both national

standards of safe and appropriate practice and health facility protocol

to prevent, recognize and treat aspiration should guide nursing actions

during the course of patient care.


28

Please take time to help NurseCe4Less.com course planners evaluate the nursing knowledge needs met by completing the

self-assessment of Knowledge Questions after reading the article, and providing feedback in the online course evaluation.

Completing the study questions is optional and is NOT a course

requirement.

1. Aspiration is defined as

a. infection of the lungs from nasal secretions.

b. movement of a foreign substance into the lungs.

c. abnormal or difficult swallowing. d. the absence of a gag reflex.

2. The most important protection against aspiration is the

a. epigastric reflex.

b. nasal reflex. c. gag reflex.

d. Babinski reflex.

3. Which of these prevents foreign objects from entering the larynx?

a. The uvula

b. The pharynx

c. The esophageal sphincter d. The epiglottis

4. True or False: Approximately 30% of people do NOT have a

functioning gag reflex.

a. True b. False

5. Which of the following are common causes of aspiration?

a. Myocardial infarction and hypertension

b. Diabetes and Alzheimer’s disease


29

c. Stroke and dysphagia

d. Irritable bowel syndrome and general anesthesia

6. An aspiration that does not cause obvious signs or symptoms is known as a

a. silent aspiration.

b. benign aspiration. c. minor aspiration.

d. simple aspiration.

7. Which of the following is a common complication of

aspiration?

a. Hyperglycemia

b. Pulmonary edema c. Fever

d. Pneumonia

8. Common signs and symptoms of aspiration may include:

a. Bradycardia and drowsiness. b. Fever and rapid breathing.

c. Hypertension and hypoglycemia. d. Hypotension and agitation.

9. Patients should be screened for aspiration risk

a. on admission and the as needed.

b. when they are being discharged.

c. if they have signs and symptoms of aspiration. d. if they are elderly females (elderly males don’t need screening).

10. Which of the following is a recommended method for

preventing aspiration?

a. Keeping the head of the bed level b. Administering tube feedings as a bolus

c. Keeping the head of the bed elevated d. Deep breathing exercises

11. In addition to the gag reflex, the __________ is also

important for preventing aspiration.


30

a. cough reflex b. nasal reflex

c. pharyngeal reflex d. Babinski reflex

12. Swallowing is the voluntary coordinated movement of food

or liquids from the mouth to the stomach.

a. True b. False

13. The oral cavity is the beginning of

a. the gastrointestinal tract.

b. the respiratory tract.

c. the respiratory tract and gastrointestinal tract. d. None of the above

14. The _____________ is a thick-walled tube of muscle and

cartilage that is located behind the larynx and the trachea.

a. gastrointestinal tract. b. esophagus

c. epiglottis d. duodenum

15. The ________________ is located at the juncture of the

esophagus, where it meets the stomach to complete the passage of food or fluids.

a. lower esophageal sphincter b. trachea

c. upper esophageal sphincter d. uvula

16. The voluntary phase of swallowing is also known as the

a. oral phase

b. esophageal phase c. automatic phase

d. oro-pharyngeal phase

17. During the swallowing process, the uvula contracts and


31

covers the opening of the nasopharynx, preventing food

from entering

a. the lungs. b. the trachea.

c. the larynx. d. the nasal passages.

18. At the same time that the larynx moves upward to close the

glottis, the __________ swings down and covers the opening of the larynx, acting like a cover.

a. esophageal sphincter b. trachea

c. epiglottis d. uvula

19. Once the food or liquid enters the esophagus it is moved

along by the action of involuntary rhythmic muscles, which is called

a. involuntary swallowing.

b. peristalsis. c. pharyngeal reflex.

d. esophageal reflex.

20. A person cannot inhale, exhale, talk, vomit, or cough when

he or she is swallowing.

a. True b. False

21. The gag reflex occurs when a foreign object touches the

a. roof of the mouth or the back of the tongue.

b. oropharynx. c. areas around the tonsils or the uvula.

d. All of the above

22. Aspiration occurs when the gag reflex and the cough reflex


32

fail to prevent a foreign substance from entering

a. the nasal passages.

b. the uvula. c. the lungs.

d. the glottis.

23. If the aspirate contains _________________ the patient

may develop aspiration pneumonia.

a. bolus

b. fluids c. infectious bacteria

d. saliva

24. Dysphagia is a medical term that means

a. difficulty in swallowing.

b. decreased level of consciousness. c. excessive production of oral secretions.

d. prolonged vomiting.

25. A serious aspiration can only occur from a large volume or

amount of a foreign substance entering the lungs.

a. True b. False

26. Which of the following screening methods is a questionnaire, not a technical test for detecting aspiration

or dysphagia?

a. Barium swallow test b. EAT-10

c. Water swallow test d. Video-fluoroscopic evaluation (VSE)

27. Specific measures for preventing aspiration include:


33

a. use of sedative drugs to relax the patient.

b. avoiding the use of antibacterial medications. c. eliminating liquids from diet.

d. measuring residual gastric volume.

28. If a patient is receiving tube feedings and she or he is at risk for aspiration, tube feedings should be

a. administered as a bolus.

b. increased based on the CNA’s observations. c. given at the prescribed rate.

d. given with sedative medication. 29. Typical signs or symptoms of aspiration include:

a. persistent, mild cough.

b. increased oxygen saturation.

c. decreased sputum production. d. All of the above.

30. Which of the following questions is useful for performing a

basic aspiration risk assessment?

a. Is patient unable to sit upright? b. Is the patient elderly?

c. Was general anesthesia recently used? d. All of the above.

Correct Answers:

1. b

2. c

3. d

4. a

5. c

11. a

12. b

13. c

14. b

15. a

21. d

22. c

23. c

24. a

25. b


34

6. a

7. d

8. b

9. a

10. c

16. d

17. d

18. c

19. b

20. a

26. b

27. d

28. c

29. a

30. d

References Section

The reference section of in-text citations include published works

intended as helpful material for further reading. Unpublished works

and personal communications are not included in this section, although

may appear within the study text.

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safety/30safe/30-safe-practices.html. 3. Blaser AR, Starkopf J, Kirsimägi Ü, Deane AM. Definition,

prevalence, and outcome of feeding intolerance in intensive care: a systematic review and meta-analysis. Acta Anaesthesiol Scand.

2014;58(8):914-22. 4. Chen S, Xian W, Cheng S, et al. Risk of regurgitation and

aspiration in patients infused with different volumes of enteral nutrition. Asia Pac J Clin Nutr. 2015;24(2):212-218.

5. Chen W, Cao Q, Li S, Li H, Zhang W. Impact of daily bathing with chlorhexidine gluconate on ventilator associated pneumonia in

intensive care units: a meta-analysis. J Thorac Dis. 2015;7(4):746-753.

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35

6. Elke G, Felbinger TW, Heyland DK. Gastric residual volume in

critically ill patients: a dead marker or still alive? Nutr Clin Pract. 2015;30(1):59-71.

7. Eom CS, Jeon CY, Lim JW, Cho EG, Park SM, Lee KS. Use of acid-suppressive drugs and risk of pneumonia: a systematic review

and meta-analysis. CMAJ. 2011;183(3):310-319. 8. Khorvash F, Abbasi S, Meidani M, Dehdashti F, Ataei B. The

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patients. Adv Biomed Res. 2014 Jan 27;3:52. doi: 10.4103/2277-9175.125789. eCollection 2014.

9. Kuppinger DD, Rittler P, Hartl WH, Rüttinger D. Use of gastric residual volume to guide enteral nutrition in critically ill patients:

a brief systematic review of clinical studies. Nutrition. 2013;29(9):1075-9.

10. Li Bassi G, Torres A. Ventilator-associated pneumonia: role of

positioning. Curr Opin Crit Care. 2011;17(1):57-63. 11. McClave SA, Lukan JK, Stefater JA, Lowen CC, Looney SW,

Matheson PJ. Poor validity of residual volumes as a marker for risk of aspiration in critically ill patients. Crit Care Med.

2005;33(2):324-330. 12. Metheny NA, Clouse RE, Chang YH, Stewart BJ, Oliver DA, Kollef

MH. Tracheobronchial aspiration of gastric contents in critically ill tube-fed patients: frequency, outcomes, and risk factors. Crit

Care Med. 2006;34(4):1007-1015. 13. Noto MJ, Domenico HJ, Byrne DW, et al. Chlorhexidine bathing

and health care-associated infections: a randomized clinical trial. JAMA. 2015;313(4):369-378.

14. Reignier J, Mercier E, Le Gouge A, http://www-ncbi-nlm-nih-gov.online.uchc.edu/pubmed/?term=Boulain

T%5BAuthor%5D&cauthor=true&cauthor_uid=23321763et al. Effect of

not monitoring residual gastric volume on risk of ventilator-

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15. Scolapio JS. Decreasing aspiration risk with enteral feeding. Gastrointest Endosc Clin N Am. 2007;17(4):711-6.

16. Shi Z, Xie H, Wang P, et al. Oral hygiene care for critically ill patients to prevent ventilator-associated pneumonia. Cochrane

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http://www.ncbi.nlm.nih.gov/pubmed/?term=Heyland%20DK%5BAuthor%5D&cauthor=true&cauthor_uid=25524884


http://www.ncbi.nlm.nih.gov/pubmed/?term=Eom%20CS%5BAuthor%5D&cauthor=true&cauthor_uid=21173070

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http://www.ncbi.nlm.nih.gov/pubmed/?term=Dehdashti%20F%5BAuthor%5D&cauthor=true&cauthor_uid=24627860

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http://www.ncbi.nlm.nih.gov/pubmed/?term=The+comparison+between+proton+pump+inhibitors+and+sucralfate+in+incidence+of+ventilator+associated+pneumonia+in+critically+ill+patients.

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36

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