RUNNING HEAD: Analysis of NG tube Insertion & Verification
PICO Analysis:
Nasogastric Tube Insertion and Verification
Nursing Best Practice
Albert Doyle
University of New Hampshire
NURS 612
Spring 2014
Doyle
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RUNNING HEAD: Analysis of NG tube Insertion & Verification
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Nursing 612 PICO Paper:
Title:
In comparing the different ways to confirm nasogastric (NG) tube placement and insertion technique in
patients requiring NG tubes, what is the best-practice for accuracy?
P: (Population) Patients requiring a NG tube.
I: (Intervention) Identifying proper insertion & placement of NG tube.
C: (Comparison) Different ways to insert & verify placement of NG tube.
O: (Outcome) Accurate verification of placement and best-practice for insertion.
Background and Rationale.
I thought this would be an interesting question to research from class discussions and my
own experiences from clinical. It seems that determining the best method for correct
placement of an NG tube is slightly vague when discussed in class and in the hospital
setting. In class, we have identified that the use of X-ray is the gold-standard in confirming
NG tube placement. However, there are also other ways that are used to assess the location
of the tube. Nurses may also test the pH of the aspirated contents, assess the color of the
aspirate, measure the tube specifically to patient before placement, and the old-school
method of pushing air down the NG tube while listening for the “swoosh” noise in the
stomach with stethoscope to check the location. Based off of my current knowledge, all of
these different methods are somewhat reliable, and still wanted to identify the best practice
RUNNING HEAD: Analysis of NG tube Insertion & Verification
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regarding the initial placement of an NG tube. Although I have never been able to be the
one performing the administration of the NG tube, I have been able to watch and assist
nurses and patients with NG tubes multiple times in clinical. Unfortunately, either the nurse
or the patient ended up feeling uncomfortable in letting a student being in control of the
procedure since I have never performed one. Which is completely understandable. I wanted
to analyze what the literature says regarding this topic to further enhance my confidence,
ability, and knowledge for when I am the nurse advancing the NG tube. In the hospital
setting, I saw feedings and medications be given without an X-ray confirmation. From what
I have seen, the nurses provide the patients with an quick, easy, and effective placement of
the tube after measurement before insertion. The placement is then double checked with the
use of pH testing or listening for the air bubble in the stomach.
As a nurse, there are several different skills and procedures that I have still not had the
chance to perform on real-life patients. Nurses on medical-surgical floors frequently start
IV access, obtain venipunctures, and place NG tubes. In comparison, nursing students
rarely have the chance to practice these skills until after graduation. Since I am slightly
unfamiliar and want to be better prepared for when I'm a first-year nurse, I want to have
the proper knowledge. “The NHS Purchasing and Supply Agency estimate that between
750,000 and 1,000,000 nasoenteric tubes are used per year [National Patient Safety
Agency (NPSA), 2005]. Between December 2002 and December 2004, at least 11
patients died from nasogastric tube (NGT) misplacement with a further non-fatal 13
incidents cited to the NPSA's National Reporting and Learning System (NRLS).” (Taylor,
p.372). Having an NG tube can have serious complications in an individual if the nurse is
to improperly place the tube and use it for feeding or suctioning while it is located
incorrectly. From the number of these tubes used each year, the preventable complications
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and deaths, I wanted to be informed for when I am the nurse for a patient requiring an NG
tube. To best prepare myself and provide optimum care for patients as a practicing nurse,
I reviewed the nursing care involved with NG tubes.
Search Methods.
For the purpose of this analysis on the insertion and confirmation of NG tube placement,
I utilized various search methods to obtain effective and relatable information. I first
accessed the UNH library website to connect to the EBSCO host. Using MEDLINE, I
was able to narrow down and specify information by searching key terms relating to my
question. I used various words to identify the five resources I used within this analysis.
These words include: NG tube, nasogastric tube, effective, best-practice, administer,
confirmation, placement, and pH. Limits I used with my searches include references
from 2004 to current time, English only, and specifically evidence-based guidelines and
other research articles/studies. Inclusion and exclusion criteria included information that
only pertained to either the act of placing and inserting an NG tube and how to best
confirm correct placement of the tube prior to use.
Critical Appraisal of the Evidence.
An nasogastric (NG) tube, is a plastic tube that is inserted into an individuals nostril,
advanced down the throat, and into the stomach. They are used for various reasons and
left in place for different durations depending on the specific patient and indicated use.
With the risk of having the tube not correctly in the stomach and possible lung entry,
serious complications can occur. This is why correct verification of tube placement in
needed before use. NG tubes are usually “intended for short-term use – typically 48-72
hours – NG tubes serve both therapeutic and diagnostic purposes” (Dulak, p.36). NG
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tube uses include administration of nutrients through feedings (intermittent or
continuous), medication administration, suctioning of gastric contents, or gastric lavage.
They are indicated for patients with some sort of upper GI complication with function
remaining in the stomach and the rest of the digestive tract. The NG tube is helpful in
patients recovering from surgery or advancing nutritional status due to imbalanced
nutrition, risk of aspiration, or difficulty swallowing.
When looking at administering an NG tube, it is important for the nurse to understand
and to be able to correctly place the tube in the correct location before use. Ensuring
best-evidence based practice for the administration and verification of the tube
placement is crucial in order for the patient to achieve the effective and therapeutic use
of the device. There are many different types of tubes that can be placed in various parts
of the body to help with a wide variety of patients with gastric issues. As a nurse, one
must be able to properly understand and perform proper NG tube administration and
care.
There are two major types of NG tubes used in the hospital setting. However, the
various medical supplies companies of these products can vary in shape, size, and other accessories
depending on the manufacturer. The major difference between the two NG tubes relates to the
number of lumens the tube has. “The Levin, [is] a flexible, soft rubber or plastic tube with a single
lumen and holes at the tip and along the distal side, is typically used for decompression, lavage, or
feeding; its not to be used for suctioning because it could adhere to and irritate the stomach's
mocosal surface.” (Dulak, p.37). When suctioning is necessary for a patient, a double lumen NG
tube is needed. A single lumen tube can cause the stomach to decompress in pressure and eventually
the end of the tube will stick to the stomach lining causing the NG tube to not work properly and
potentially lead to other issues. The Salem NG tube has two lumens, where one is used for same
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functions as the single-lumen with the addition of suctioning. The second lumen is left open to the
outside air creating a vent between the stomach and atmospheric pressure. This allows the
stomach's pressure to remain at a adequate level during feedings and suctioning. The Salem NG
tube is more common and helps relieve abdominal discomfort even for patients who do not require
suctioning. “The vent allows atomospheric air to continually flow into the stomach,preventing the
tip of the NG tube from adhering to the gut wall, making this tube ideal for use with suction.”
(Dulak, p.37). It is important that nurses identify the different types of NG tubes to insure that they
are being used correctly. Nurses should also remain aware that the double-lumen vent should never
be used for suctioning or administering anything. The vent should be left open and both lumens
should be checked frequently to maintain proper functioning.
To ensure a proper administration of NG tube, a nurse must first know the
instructions on how to place one. Before attempting placement for the first time in practice, it is
recommended that an individual first watches or assists with the administration and reviews the
correct steps. Prior to inserting the NG tube, a nurse will need the correct NG tube kit, “an emesis
basin, towel, tissues, water-soluble lubricant, non-sterile gloves, and an irrigation set (if required),
safety pin, and ice chips or a cup of water with a straw.” (Dulak, p.37). The suction in the room
should be properly set up and working before placing the NG tube. Once the correct materials are
gathered, the procedure should be explained to the patient and be educated on why this tube is
indicated for them. At this time, they should be given instructions regarding the NG tube for a safe
and effective use. The thought of having a tube being put into one's nose, down the throat, and into
the stomach, can seem uncomfortable and scary for most individuals. Discomfort is expected with
the administration of an NG tube and each patient should be assessed on how they will feel once the
tube is inserted. If the patient is unconscious or sedated, the NG tube insertion may easier due to
lack of gag reflex and inability to sense the discomfort. However, patients that are alert and oriented
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to their surroundings, may have some anxiety and fear for the invasive procedure. It is important to
premedicate per provider orders or encourage and support the patient to be prepared for the
insertion phase. The individual must know what to expect before the nurse enters the room with the
materials. They should be instructed not to pull on the tube once in place and during the insertion.
Patients should know that they may experience coughing, gagging, tearing, feeling like they are
going to throw up, and other discomfort with the tube. To facilitate the right path for the tube to
travel and make the patient feel more comfortable, it is “essential that [the individual] swallow as
directed to ease tube insertion.” (Dulak, p.37). The use of sips of water during advancement of the
tube has been shown to be a helpful guideline to follow to aid in the correct placement in the
stomach and a less resistant and uncomfortable insertion for the individual.
Once the nurse and patient are ready for the bedside insertion of an NG tube, the
nurse should use a pen light to assess the patency of both nares. The nurse should also identify a
deviated septum or other nasal deformities that may cause a potential obstacle when advancing
tube. If the both nostrils are congested, the patient should blow their nose before selecting which
nostril to be used. It is suggested that the patient removes any dentures or retainers to prevent
choking during the procedure. The patient must then be brought into high fowlers positioning, with
the head and back supported by either a pillow or another person to help encourage the patient
during the insertion. This provides an optimal anatomical position to best direct the tube into the
individual's stomach and decreases the risk of aspirating fluid into the lungs. A towel should be
draped around the patients chest with the tissues and emesis basin within patient or assistant reach.
Although this procedure is non-sterile, it is essential for the nurse to ensure standard precautions
and best clean technique is used with the risk of the tube accidentally entering the respiratory tract.
Correct measurement of the tube prior to the procedure aids in a more effective placement. The
length required to reach the patients stomach is performed by “extend[ing] the end of the tube from
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the tip of [the] nose to [the] earlobe, then down to the xiphoid process. Mark the distance with a
piece of tape. The average length for an adult is 22 - 26 inches.” (Dulak, p.38). After identifying
which nostril to use, gloves applied, the tip of the tube is lubricated, and the patient is ready, the
nurse can attempt insertion. “With the curve pointing downward, carefully insert the tube along the
floor of the nostril, on the lateral side” (Dulak, p.38). As the tube passes the nasal cavity, it may get
coiled up at the back of the throat. If this occurs, the tube should be pulled out until there is no more
coil and reinserted until it advances down the throat. As the tube is being advanced, there may be
some resistance once the nasopharynx reached. This is a likely spot that may cause the patient to
cough, gag, or vomit. If this occurs, the patient should be instructed to tilt their head forward. This
positioning will close the trachea and make it easier for the tube to pass through the esophagus.”
(Dulak, p.38). Sips of water should be used with each advancement of the tube past the oropharynx.
If the individual continues to cough, starts to choke, or is unable to talk, the tube should be brought
slightly back out since it may have entered the trachea. If this doesn't help, the nurse should check
the “mouth to see if the tube has become coiled at the back of the throat. If so, slowly withdraw the
tube until it is straight and allow the patient to rest briefly before [attempting] again.” (Dulak, p.38).
After the tube has reached where it was marked during measurement and the patient's cough or gag
has subsided, the nurse must secure the tubing.
The NG tube must be properly secured in order to prevent dislodging the current
location and prevention of skin breakdown. The part of the tube that extends from the patient's nose
should be pinned to the johnny to prevent the NG tube from hanging freely. If the NG tube does not
come with a dressing or strap for the nose, the split tape method can be utilized. To do this, the
nurse should tear off about four inches of tape and split “it lengthwise to about the halfay point.
After creating tabs on the split ends, tape the unsplit end to the end of the nose and crisscross the
split ends around the tube.” (Dulak, p.39). This helps protect the skin around the nostril from the
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pressure of the tube. Over the time the tube is in place, health-care workers and nurses must
continue to assess the location of the NG tube and the skin surrounding the tube.
After the tube has been administered, the tube must be accurately confirmed in the
correct location prior to its indicated use. Guidelines recommend using “the AAA system to
remember the steps to ensure correct NG tube placement and prevent aspiration.” (Sweeney, p.25).
The first A, stands for assess, which should also be done prior to administration. It is important to
inspect the abdomen, auscultate for bowel sounds, percuss, and palpate for any distention or
tenderness. When in place over time, it is crucial nurses assess the rate of feedings and/or
suctioning per physicians orders while identifying how well the equipment and individual is
responding to the functions of the NG tube. In the case of tube malfunction, patient complaint, or
other reason suspecting something isn't working correctly, nurses should ensure that the
measurement of the tube at the end of the nostril is at the same length from when placement was
confirmed. The tube could have been disrupted and misplaced out of the stomach if the length is
less than what it was originally. Nurses should instruct the individual not to tug at the tube and alert
the nurse regarding any issues or discomfort. After assessing the patients status and tube, the
administration of air can be used to help identify NG tube placement. However, this way is not
recommended alone to ensure proper placement of the tube. Putting in air and listening for a
“whoosh” sound, frequently used to be performed by nurses in the past. Research over time has
proven that this is not best practice because the same “whoosh” noise can be heard when the tube
has entered the respiratory tract. Since “tube misplacement in the tracheobronchial tree is
potentially fatal,” (Taylor, p.372), other methods must be used to verify placement. Although “an
NG tube in the respiratory tract can transmit a similar sound,”(Dulak, p.39), this is still performed
by “older” nurses with previous NG tube experience. Even though it is still seen in practice, nurses
must be aware that confirmation by this method alone is contraindicated.
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Testing the pH of the gastric contents once the tube has been placed is shown to be
reliable in determining proper location. Based on the evidence regarding pH testing, there is a grayarea in determining the exact pH values aspirated contents in the stomach have. This is mostly
because of the multiple factors that can influence an individuals pH. The pH of NG tube aspirate
can change depending on age, medications, diet, or where the tube is located. “Gastric contents will
always be acidic (<5.6pH), while fluid from the pulmonary tract will be alkaline (>6pH).” (Dulak,
p.39). Another source stated that “gastric tube aspirate has a pH of 5.5 or less.” (Sweeney, p.25). If
the individual aspirated gastric fluid into the trachea and lungs, the pH may reveal an acidic pH
level. When assessing the pH of the aspirated contents, the nurse should also inspect the color of the
aspirate. Stomach aspirate is “grassy green, while intestinal fluid tends to be golden and
translucent.” (Dulak, p.39). Fluid from the tracheobronchial tree is usually clear or white and
mucous-like. Aspirated contents can also be collected and sent to lab for analysis for cause of
certain GI problems such as a bleed and/or drug overdose via medications or chemicals.
Evidence Synthesis.
Based on the literature and evidence reviewed, there are no real major differences in
the instructions on how to best insert an NG tube. All sources emphasize patient teaching and
cooperation throughout the use of an NG tube. They also focus on positioning, use of sips of water,
patient specific measuring of the tube length, and other techniques to facilitate an efficient and
adequate placement of the device. Prior to administering an NG tube, the nurse must verify that the
patient understands the procedure. The nurse should always verify that the use of an NG tube is
indicated for the patient and will be beneficial for their health. The primary risk a nurse should be
aware of is introducing foreign objects into the patients respiratory tract with the risk of infection.
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Various precautions and steps are used to reduce the chance of complications. For example, oil
soluble lubricant, like petrolleum jelly is contraindicated for NG tubes because “they can't be
absorbed by the pulmonary mucosa and may cause pneumonia if accidentally introduced into the
trachea.” (Dulak, p.38). Preventative measures to not use the tube until placement is confirmed also
helps reduce the risk of respiratory problems.
When looking at confirming the placement of an NG tube, various sources
rationalize and explain through evidence the different pros and cons of various techniques and
methods. NG tube verification can vary depending on hospital protocol. The risk of confirming a
correct placement when it is incorrectly located causes “many facilities [to] require radiologic
confirmation before using the NG tube for feeding or medication administration.” (Dulak, p.39).
Before advancing the tube, proper measurement is shown to aid in a successful placement.
Following correct steps and instructions during the procedure is also important to assist a proper
placement. Although there is no harm in assessing the abdomen and listening for the air “swoosh”
sound, these techniques should not be practiced and are not reliable ways to confirm placement.
Testing pH of gastric contents is the second best way to check the tubes placement.
Many patients in the hospital are on proton-pump inhibitors and H2 blockers. These medications
alter the individuals pH, “potentially giving a false negative result and making differentiation of
position impossible” (Taylor, p.372) when testing the aspirate from the NG tube. The pH of the
stomach can also vary depending on the individuals recent intake. Acidic drinks like orange juice or
foods such as squash can alter the individuals pH. Nurses should “establish the fluid pH prior to
drinking and minimize use of other fluids during intubation to avoid dilution and raising the pH”
(Taylor, p.374). The pH can differ depending on the age of the individual. One study analyzed pH
testing on the pediatric population. “Studies indicate that pH ≤ 4 confirms gastric aspirate, but in
pediatrics, a pH of gastric aspirate is often >4.” (Gilbertson, p.540). It was concluded that a pH of ≤ 5 is
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a better measurement of pH in the pediatric population. Overall, pH testing is effective and can be
used to identify correct placement. The nurse must be aware of the patient they are caring for as to
any reason for an abnormal pH. If the nurse is have a gut feeling the tube is misplaced or the pH
reading continues to be abnormal, they should resort to the gold standard of checking placement.
Taking an Xray to confirm placement is the most accurate way in identifying NG
tube location. The Xray image will be able to produce and determine the exact location of the tube.
However, it usually takes some patience and time while waiting for a Xray confirmation. “Weighing
the balance of risks between having to move the patient to radiology, malnutrition incurred by delay
and the risk of irradiation itself when checking position by X-ray, bedside pH testing has been
recommended as the first-line method for confirming NG tube position.” (Taylor, p.372). Testing
the patient's pH is an adequate way of determining position if the nurse can correctly identify the
placement by taking all of the various factors into consideration. In conclusion, nurses should await
for Xray confirmation prior to NG tube use if they are unable to verify correct placement via pH
testing.
Clinical and Research Recommendations.
Based on what I have reviewed, I have been able to establish a strong knowledge
base and foundation regarding the proper steps and instructions to best insert an NG tube. Nursing
students and nurses should be familiar with this process in order to effectively and efficiently
administer an NG tube. This is also true with confirming the placement of the tube. The various
methods analyzed are all useful in determining the location of the tube. Assessing and testing the
pH of aspirate can be accurate in identifying location as well. More studies could be performed to
best understand how to prevent pH testing mistakes to adequately measure and test the contents.
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Xrays are the most reliable indicator of NG tube placement. However, they require patience,
transportation, and the harmful exposure to radiation waves.
I stumbled upon a study which revolved around a new approach in confirming NG
tube placement. “A small permanent magnet was attached at the end of an NG tube and it's position
was monitored using an external sensor array connected to a computer. NG tube trajectory, spontaneous
movements of the magnet, and its position relative to the lower esophageal sphincter (LES) and
xiphisternum were assessed in 22 healthy subjects and compared with esophageal manometry.” (Bercik,
p.305). This method results in quick confirmation of the tube during insertion and also has no risk in
exposure to radiation. More research could be done regarding this type of NG tube to determine
effectiveness across a wider population and making it cost effective. “T he magnet-tracking technique
is easy, safe, and accurate, offering a number of potential applications relevant to clinical nutrition
and gastroenterology. It can be used to monitor tube placement, providing a pseudo-3D display of
the magnet’s position in real time, and it can verify the position of the magnet by sensing GI tract
motor patterns.” (Berick, p.310). In the future, I predict that NG tubes will come with detectors like
this to allow a one step, universal way of verifying and monitoring the position nasogastric tubes.
In conclusion, this analysis and review of NG tube nursing care has provided me with a
foundation to bring with me into the hospital setting. I feel more confident in my ability to perform the
insertion and prevent any complications by using the NG tube correctly and accurately verifying the
location before use. Although this has been educational, I have deeply enjoyed understanding the
evidence and rationale behind NG tubes. Based on this analysis and most of all, the two semesters of
Med-Surg, I feel much more prepared, eager, and confident in my ability to provide optimal nursing
care to various individuals in need.
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References Cited:
Bercik, P., Schlageter, V., Mauro, M., Rawlinson, J., Kucera, P., & Armstrong, D. (2005). Techniques.
materials, devices. Noninvasive verification of nasogastric tube placement using a magnettracking system: a pilot study in healthy subjects. JPEN Journal Of Parenteral & Enteral
Nutrition, 29(4), 305-310.
Dulak, S. (2006). Hands-on help: practical tips for the bedside. Inserting an NG tube. Healthcare
Traveler, 14(2), 36-41.
Gilbertson, H., Rogers, E., & Ukoumunne, O. (2011). Determination of a Practical pH Cutoff Level for
Reliable Confirmation of Nasogastric Tube Placement. JPEN Journal Of Parenteral &
Enteral Nutrition, 35(4), 540-544. doi:10.1177/0148607110383285
Sweeney, J. (2005). Clinical queries. How do I verify NG tube placement?. Nursing, 35(8), 25.
Taylor, S., & Clemente, R. (2005). Confirmation of nasogastric tube position by pH testing. Journal Of
Human Nutrition & Dietetics, 18(5), 371-375.