Pittsburgh EMS

Pre-Hospital Care
Monograph

COMBITUBE

Center for Emergency Medicine

OF WESTERN PENNSYLVANIA
 DEDICATION

This monograph is dedicated to the men and women of the City of Pittsburgh EMS
System who have provided outstanding prehospital care in the City of Pittsburgh for
over two decades.

This monograph was created by the Medical Directors of Pittsburgh EMS with the
assistance of the City of Pittsburgh, EMS Training Division.

Medical Direction Committee

City of Pittsburgh Bureau of EMS

Paul M. Paris, M.D., FACEP Ronald N. Roth, M.D., FACEP

Medical Director Associate Medical Director

Vincent N. Mosesso, Jr., M.D., FACEP Theodore R. Delbridge, M.D., M.P.H.

Assistant Medical Director Assistant Medical Director

John Cole, M.D. EMS Fellows

Assistant Medical Director Ritu Sahni, M.D.
Owen Traynor, M.D.
Guillermo Pierluisi, M.D.

A special thanks to John Cole, MD and Jeff Reim, EMT-P for developing and writing
this module. The Combitube represents an additional tool for securing the airway in an
unresponsive victim. The Combitube does NOT replace endotracheal intubation but
provides a new option for securing the airway when endotracheal intubation has been
unsuccessful or in a few unique situations where endotracheal intubation is not
possible.

As with all airway adjuncts, it is critical that paramedic “know where the tube is” and
confirm the tube placement by multiple methods. Make sure that you understand the
anatomy of the Combitube and the way to confirm it’s location in the esophagus or
trachea.
Ron Roth, MD-2
June 1998
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The Combitube - Overview

Introduction
Although endotracheal intubation is the preferred method of airway maintenance in
critically ill patients, it is not always possible to intubate every patient that requires
definitive airway control. The ideal adjunctive airway would provide adequate
ventilation and oxygenation of patients while preventing aspiration. The Esophageal
Obturator Airway (EOA) was plagued with problems of accidental tracheal placement,
poor mask seal, and poor ventilation and oxygenation in some studies.

The Esophageal Tracheal Combitube is a dual lumen tube with two balloon cuffs. The
tube is inserted blindly, and ventilation can be achieved with either tracheal or
esophageal placement. The Combitube is placed in the esophagus 85% of the time. A
large proximal balloon that seats itself behind the hard palate surrounds the dual lumen
tube. This balloon displaces the soft palate posteriorly and occludes the airway
proximal to the larynx. The smaller distal balloon provides a cuff for the distal end of
the tube.

Lumen #1 is sealed at the end but contains

fenestrations (holes) distal to the lumen 2
pharyngeal balloon. Lumen #1 is used to
ventilate the patient when the tube has balloon 2

been blindly inserted into the esophagus, esophagus balloon 1

100cc
approximately 85% of the time. Lumen #2 holes lumen 1

ends beyond the small cuff balloon similar trachea

to an endotracheal tube. Lumen #2 is used to ventilate the patient when the tube has
been blindly inserted into the trachea.

Ventilation studies have shown that the Combitube can be used for extended periods of
time while providing adequate oxygenation and ventilation as documented by arterial
blood gases. The Combitube provides adequate oxygenation and this has been
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documented in the ICU, operating room, and during CPR. In a prehospital study,
resistance on insertion was the most common reason for failed insertion. No major
complications have been reported as common occurrences. In a study of 1200
prehospital patients, only two esophageal lacerations occurred.

The Combitube can only be used in the unresponsive patient without a gag reflex or
patient’s in cardiac arrest. After checking the balloons and lubricating the tube, the
paramedic uses his/her non-dominant to lift the tongue and jaw. Release cricoid
pressure that may have been applied during BVM ventilation. The dominant hand is
used to slide the tube GENTLY along the roof of the mouth. Advance the tube until the
upper teeth or gums are aligned between the two black rings. The Combitube should
never be forced. If resistance is met, withdraw the tube, reposition the head and re-
attempt. If you are unable to place the tube within 30 seconds, hyperventilate patient for
1 - 2 minutes and re-attempt. If the tube will not pass on the second attempt, ventilate
with a BVM and notify Command. Limit to 2 attempts prior to contacting Command.

Once the tube is in place, inflate large pharyngeal balloon (blue #1 cuff) with 100 cc air.
Then inflate distal balloon (white #2 cuff) with 15 cc. Begin ventilating through the
longer blue tube (#1).

Assess placement of the tube by:

• Observing the chest rise and fall.
• Listening for bilateral lung sounds.
• Listening over epigastrum for air gurgling in stomach.
• Watch for color change of CO2 detector. (*remember that the detector may not
change colors in cardiac arrest patients who are not generating CO2)

Do NOT use the Esophageal Detector Device (Bulb) with the Combitube.
Identifying the location of the tube is the most critical step in the use of the Combitube.
Remember that the tube may be in 1) the esophagus, 2) the trachea, 3) too far down
the esophagus, or 4) somewhere else. (See chart on the next page)
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Assessment Location Action

bilateral lung sounds - present esophageal placement Continue ventilating with
stomach sounds - absent 100% oxygen through the
*CO2 detector - changes #1 tube.
chest rise - good

lung sounds - absent tracheal placement Switch the bag valve to the
stomach sounds - present shorter tube (#2), and
(hear gurgling in the stomach) reassess placement as
*CO2 detector - no change above.
If there are bilateral lung
sounds, absent stomach
sounds, and good chest rise
while ventilating through the
#2 tube, this
indicates tracheal
placement. Continue using
#2 tube
lung sounds - absent too far down the Deflate balloon #1, pull back
stomach sounds - absent esophagus, or somewhere the tube 2-3 centimeters ,
*CO2 detector - no change else. re-inflate the balloon and
reassess placement as
above.
If there are bilateral lung
sounds present, absent
stomach sounds, and good
chest rise, *CO2 detector
change the tube is in place.
Continue ventilating with
*remember that the detector may 100% oxygen through the
not change colors in cardiac arrest #1 tube.
patients who are not generating If lung sounds are absent,
CO2 absent stomach sounds,
and no *CO2 detector
change remove the tube
and ventilate with a BVM
and oral airway.
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Once the position of the tube is confirmed, secure tube with a tube holder and monitor
the patient’s condition. Use pulse oximetry in the non-cardiac arrest patient. Low
readings may indicate ineffective ventilations. Falling readings may indicate that the
incorrect tube lumen is being used. Direct visualization with laryngoscope can be used
to confirm tube position, however the large balloon (#1) must be deflated to visualize
the posterior pharynx.

If the device is placed in the esophagus, the #2 tube can be used to relieve gastric
distention using the stomach catheter provided. If the tube is in the trachea, ventilation
will occur through tube #2. Drugs may be administered though this tube.

To prevent accidental use of the incorrect tube lumen once the tube position has been
identified, place a piece of tape over the lumen not being used. Make sure that all crew
members and the physician are aware of the location of the tube (esophagus vs.
trachea) and which tube lumen is in use (#1 vs #2).

Upon arrival at the medical facility, the large syringe should be brought into the ER to
facilitate deflation of the pharyngeal balloon (#1).

The Combitube should not be removed in the field unless:

• Patient regains consciousness and no longer tolerates the tube (begins to gag).
• Ventilation is inadequate.
• Tube placement cannot be determined.

Before removing the tube, have suction equipment ready. Log roll the patient to the
side. Then, deflate pharyngeal balloon #1 with the large syringe followed by distal
balloon #2. Make sure that both balloons are completely collapsed prior to removing the
tube. While suctioning the airway, gently remove the Combitube.
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Endotracheal intubation with a laryngoscope can be performed with the Combitube in

place.
If the Combitube is in the esophagus, completely deflate pharyngeal balloon #1
with the large syringe. Use the laryngoscope blade to sweep the tube and
tongue to the left. Visualize the cords and intubate the trachea. Confirm proper
positioning of the endotracheal tube. Deflate balloon # 2 and carefully remove
the Combitube while securing the endotracheal tube.

If the Combitube is in the trachea, hospital personnel may elect to change the
tube over a “tube changer” or remove the tube and intubate in standard fashion.

Since some hospital personnel may not be familiar with the Combitube, please assist
them with it’s use.
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The Combitube
Advantages
· Effective ventilation and oxygenation with moderate protection against aspiration.
· Blind insertion without the need for light, laryngoscope, or direct visualization of
vocal cords.
· Posterior pharyngeal balloon solves the problem of poor mask seal often
encountered when using an EOA.
· Gastric contents can be aspirated through lumen #2 when the device is in the
esophagus (85% of the time).
· Pharyngeal balloon may be independently deflated to allow direct visualization for
endotracheal intubation.

Disadvantages
· Medications can not be administered through the Combitube when it is in the
esophageal position (85% of the time).
· The trachea cannot be suctioned when the Combitube is in the esophageal position.

Indications
· Unresponsive patients without a gag reflex
· Three (3) unsuccessful attempts at endotracheal intubation
· Limited access to patient’s head, i.e. entrapped patient
· Potential c-spine injury with inability to visualize vocal cords

Contraindications
· Conscious or unconscious patient with a gag reflex
· Known esophageal disease (cancer, varices, or stricture)
· Caustic oral ingestion
· Patent tracheotomy
· Patient height less than 5 feet
· Patient age less than 16 years (unless greater than 5 feet tall)
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Combitube Procedure
• Ensure adequate ventilation with high flow oxygen and cricoid
pressure if possible

• Check Combitube balloons and lubricate distal end of tube

• Lift patient’s jaw and tongue forward with non-dominant hand.

Discontinue any cricoid pressure.

• Gently insert Combitube in midline of mouth following natural

curvature of the pharynx

• Insert Combitube until the teeth or alveolar ridge are between the
black lines on the tube. Stop if resistance is felt during insertion.

• Inflate blue pilot balloon (#1) with 100cc of air using provided syringe.

• Inflate white balloon (#2) with 15cc of air using provided syringe.

• Attach end-tidal CO2 detector to Blue tube (#1) and ventilate with
Bag-valve.

• Confirm tube placement by auscultation over epigastrium and lungs

as well as end-tidal CO2 color change. If bilateral breath sounds are
present and epigastic sounds are absent, continue ventilating
through tube #1 (blue tube)

• If gastric sounds are heard or if no lung sounds are heard, or if no

color change is seen on the end-tidal CO2 detector, immediately
switch to ventilating the clear tube (#2) with the bag-valve.

• Repeat auscultation of epigastrium and lungs and attach end-tidal

CO2 detector. If bilateral breath sounds are present and epigastic
sounds are absent, continue ventilating through tube #2 (clear tube).

• If ventilation is not adequate and no breath sounds and no gastric

sounds are heard the Combitube may be advanced to far,
immediately deflate balloon #1 and move the Combitube out 2-3 cm
out of the patient’s mouth. Reinflate balloon #1 with 100cc of air and
attempt to ventilate. If auscultation of breath sounds is positive and
auscultation of gastric insufflation is negative, continue ventilation.

• If ventilation is not adequate then deflate both balloons and remove the tube.

• Ventilate patient with bag-valve mask until a definitive airway is established at the hospital.
 Combitube Airway
y C h e c k b o t h c u f f s f o r i n t eg r i t y
y Lubricate tube
y Insert tube until teeth are between black lines
y Inflate Balloon #1 with 100cc of air using the
140ml syringe
y I n f l a t e B a l l o o n # 2 w i t h 1 5 c c o f a i r u s i ng t h e
20ml syringe

Attach CO2 detector to BVM and begin

ventilation via tube #1 (Blue Tube)
y Auscaltate chest and gastric area

Good breath sounds Ventilation sounds over No sounds heard over

bilaterally the stomach chest or stomach

The tube may be too far

Continue ventilation Switch to tube #2 in the pharynx
via Blue Tube (Clear Tube) -Deflate Balloon #1, withdraw
-May use clear tube for -Begin ventilation and the tube aprox. 2-3cm.
suctioning stomach confirm good breath -Reinflate Balloon #1 and
-No drugs down the tube sounds bilaterally, CO2 ventilate via tube #1 (Blue
detector change and no Tube)
breath sounds over the -Reassess breath sounds over
s t o m a c h. chest and stomach
-May put drugs down the -If good breath sounds are
tube heard over chest, continue
ventilation via Blue Tube
-If breath sounds are not heard
over chest, remove tube and
ventilate with BVM