How to Improve Oxygenation and Patient Safety by
an Ineffective Nasal Cannula to
Technically Simple and Effective
Face Tent in 10 seconds.

Safe and Effectiveness Use of  Nasal TSE-PAP Mask Assembly  in  
Sedated Patients with Obstructive Sleep Apnea, Patients with
Difficult Airway for Awake Intubation or Patients with Poor
Face-Mask Fit for GA Induction.

9 Awards

What is this?      Just a plastic bag?!

"It is a Tse mask!" Charles Brandwein, MD, 2001

"It is Totally Simple and Easy!"
Jacqueline Gladdis, R.N., 2006

"So Easy! Anesthesiologists can do it!!"
James Tse, PhD, MD

"Why don't you call it 'TSE-Alloteh CPAP'?"
John Denny, MD, 2013

"Nasal Tse-PAP Mask Assembly" Jack (John A.) Pacey, MD,
FRCSc, GlideScope Inventor, 2015


The demand for off-site anesthesia care
has been increasing in the recent years
at the Robert Wood Johnson University
Hospital in New Brunswick, NJ.

The off-sites include
Endoscopy/Bronchoscopy Suite, Cardiac
Echo Lab, Cardiac Cath Lab,
Radiology/Special Procedure Suite, CT-
Scan/MRI Suite, Infertility Clinic, ER
and ICUs.

These off-sites pose many
challenges for anesthesia care
providers, such as less-than-ideal
anesthesia set-ups, small crowded
and dark rooms, help from
another anesthesiologist is far
away, production pressure for
rapid turnover, high expectation,
high-risk patients
, etc.

It is especially challenging during
bronchoscopy and TEE.  

An O2 reservoir is lost when the
patient’s mouth is kept open with a
bite block (Photo 1).
A nasal cannula
becomes ineffective and delivers only minimal
(<0.30 FiO2).

Furthermore, the airway is often
compromised by the endoscope.

Oxygen desaturation is a common
occurrence in patients receiving
moderate-to-deep sedation during
upper GI endoscopic procedures.

According to ASGE Guideline (2012),
large series report adverse event rates
of 1 in 200 to 1 in 10,000 and mortality
rates ranging from none to 1 in 2000.
Data collected from the Clinical
Outcomes Research Initiative
database show a cardiopulmonary
event rate of 1 in 170 and a mortality
rate of  1 in 10,000 from among  
140,000 UGI endoscopic procedures.
For more information, please go to

Guideline: Adverse Events of Upper GI
Endoscopy, BSG Guidelines in Gastroenterology:
Complications of GI Endoscopy and SGNA Risks
& Complications

We have used a simple plastic sheet
to convert an ineffective nasal
cannula to a face tent since 2001
(Photo 2-5

It takes 10 seconds to prepare at bedside
and provides FiO2 of 0.50-
0.70 with the nasal cannula O2 flow
of 4-5 L/min.

It improves patient’s oxygenation,
prevents severe desaturation,
decreases the need for assisted
ventilation and reduces the
interruptions of the procedures.

How to Make a TSE

We make a 12" x 12" or larger plastic
sheet utilizing any clean, clear plastic
bag (nasal cannula bags, specimen bags,
face mask bags, breathing circuit bags,
etc.) or the clear plastic shield of a fluid-
shield surgical mask .

After the patient assumes the lateral
decubitus, prone or supine position, we
put a nasal cannula on the patient and
then place a clear plastic sheet over the
patient’s head covering the eyes, the
nose and the mouth, and secure it with
(Photo 2-7)

In less than 10 seconds, a nasal cannula
is converted into a face tent that
provides FiO2 of 0.50-0.70 with O2
flows of 4-5 L/min.

Upper GI Endoscopy, FOB
or TEE
During manipulation of the endoscope,
we lift the plastic sheet slightly to avoid
dragging it into the mouth.

The zip-lock specimen and face mask
bags are easy to use because the rigid
edges can stand up like a tent with an
open door
(Photo 2-4)

The soft plastic sheet can also be re-
enforced with one-inch silk tape.
(Photo 5)
When we use a plastic shield from
a fluid-shield surgical mask, we
tape the plastic sharp edges to
avoid corneal abrasion.
(Photo 6)

After explaining to the patient that by
applying this plastic sheet we will be
increasing O2 supply and ask the patient
to close  the eyes, even the most anxious
patients are receptive.

Following pre-oxygenation using this
technique for 1-2 minutes, we titrate
propofol or other sedatives to achieve
moderate-to-deep sedation while
maintaining spontaneous respirations.

Keep a Patent Airway and
Monitor Respiration

We position patient’s head and neck to
maintain a patent airway.
For patients with upper airway
obstruction, serial dilation with well-
lubricated nasopharyngeal airways may
avoid causing nasal bleeding.
We monitor the patient’s respirations
using capnography, with or without a
pediatric precordial stethoscope placed
over the trachea.
This face tent also improves CO2
sampling and makes early detection of
respiratory depression possible.
If the patient becomes apneic because of
airway obstruction or over-sedation, we
have an average of
2-3 minutes to
manipulate the airway and/or to
decrease the level of sedation before
desaturation occurs.

Rebreathing of CO2?

One concern is that a plastic sheet could
increase "dead space" resulting in re-
breathing of CO2 and hypercarbia.
We routinely monitor CO2 using
capnography. By maintaining the plastic
sheet in
a tent-like position with an open door,
we can avoid re-breathing of CO2
(Photo 7).

Monitored Anesthesia Care   

The line between deep sedation and total
intravenous anesthesia is very fine.
Deep sedation often turns into general
Anesthesia providers should always be
ready to manage patients under general

If a nasal cannula is used for deep
sedation, a TSE "Mask" will improve
patient’s oxygenation.
We have used this face tent for short
(D & C, hysteroscopy, LEEP,cystoscopy).

If opioid analgesic is needed, titrating in
small increments of analgesic would
maintain spontaneous respiration.

Patient selection is important to
decrease the risk of pulmonary

Premedication of the patient with
metoclopramide may decrease the risk
of gastric reflux.

Mask/Circuit Assembly to
deliver CPAP, BiPAP, CF
(continuous flow) or
Assisted Nasal Ventilation
for Patients with or without  
OSA under MAC (EGD,
colonoscopy, bronchoscopy,
TEE, etc.), Awake
Intubation or GA.

(Provisional Patent filed on Oct 30,
2013 and Formal Patent Application
filed on Oct 29, 2014 by Rutgers
University for a similar assembly.
James Tse and co-inventors have
transferred the invention to RU for one

(Please see updated Practice
Guidelines for Perioperative
Management of Patients with
Obstructive Sleep Apnea.

Anesth 120: 268-86, 2014 or
Google search "2014 ASA
Guidelines OSA" for a pdf link)

Patients under monitored
anesthesia care (MAC) receive
intravenous sedation and O2 via
nasal cannula (NC). Over-sedation
and/or airway obstruction may
cause severe desaturation,
especially in obese patients with

Even with a face tent (TSE
"Mask"), obese OSA patients may
require frequent chin-lift, jaw-
thrust and/or insertion of nasal

Inserting nasal airways may cause
bleeding despite using small, well
lubricated nasal airways.

On January 24, 2013, a nasal TSE-
PAP mask/circuit was developed
using an infant face mask (Photo
11-13). It  was successfully used in
3 sedated patients with  and
without OSA the next day to
improve spontaneous ventilation
and oxygenation during EGD.

The effectiveness of nasal
ventilation in anesthetized
patients and unconscious apneic
adults has been shown by Liang
et. al. (Anesthesiology 108: 998-
1003, 2008
  Anesthesiology 108: 998-1003, 2008) and
Jiang et. al. (Anesthesiology 115:
129-35, 2011
 Anesthesiology 115: 129-, 2011)

The nasal TSE-PAP mask is
especially useful for EGD and TEE
under MAC. With the bite block in
place, CPAP is about 1-2 cm of
H2O even with the APL valve
completely closed.  

However, it becomes CF mask with
fresh O2 flow of 4-5 L/min. Fresh
air can be added to keep FiO2
under 0.8 to avoid causing
absorption atelectasis (Photo 11-

Adjust the APL valve to deliver 4-8
cm H2O CPAP as needed and
avoid over-inflating the reservoir

If the patient becomes
apneic or the airway is
obstructed by the
endoscope, assisted
ventilation can be
immediately delivered
without interrupting the
procedure. It should be
done with small volume to
keep PIP under 20 cm of
H2O to avoid gastric

Should you have any
question for the safe
use of this technique,
please contact us via

or email (

It improves oxygenation
and can be used to pro-
actively  prevent
desaturation in obese
patients with OSA.
( Please see Publications #70 & 71,
81-85, 87-95)
(Patients consented for

This nasal mask assembly
has also been used for
awake FOB and/or video
laryngoscopy assisted
endotracheal intubation
(Photo 19a-c) and
preoxygenation and assisted
nasal ventilation for
patients with poor face-
mask fit during induction of
general anesthesia
(Please see Publication and Presentation).

A Modified TSE "Mask"
for Upper Body

Fire Hazard Precautions

Do not use a plastic bag or
a plastic sheet
for upper
body procedures, such as
breast biopsy or thyroidectomy
avoid high O2
concentration Pooling
under the surgical drapes.

Taping a fluid-shield surgical
mask firmly to the lower jaws will

the risk of  FIRE
(Photo 22-24)
It increases O2 supply to the
patient and avoids O2 pooling
under the surgical drapes close to
the surgical site.

Our preliminary data show that
O2 concentration under the
surgical drapes is close to 22% by
using this modified TSE "Mask".

It also keeps the surgical towels or
drapes from
covering the patient's face.

It is very important to
protect the eyes. Tape the
sharp edges of the plastic
shield to avoid corneal
(Photo  22-24)

Even though there are
commercially available devices for
endoscopies or for patients with
mouth breathing (Photo 20-24),
this technique utilizes plastic
sheets which are ubiquitous and
available at no additional cost.

We also use this technique for patients
undergoing rectal procedures in the
jack-knife position (Photo 25), pain
management procedures in the prone
position, retrobulbar block (Photo 28)
and pediatric procedures (endoscopy,
PICC, spinal tap, bone marrow biopsy,
MRI, CT Scan, etc.).

Prone Position: Use pillows to
support the upper body and head
to maintain a patent airway.
For patients with upper airway
obstruction, serial dilation with
well-lubricated nasopharyngeal
airways and chin lift may open the
airway. Use a large clear plastic
sheet to create a large O2 hood
(Photo 8 & 25).

If patient's oxygenation fails to
improve, attaching an anesthesia
breathing circuit to a
nasopharyngeal airway using an
ETT connector delivers high
concentration of O2 directly into
the oropharynx (Photo 26-27):

1. The connector from a 7.0 ETT
fits well with 30-34 Fr
nasopharyngeal airways (so does a
6.0 or 8.0 ETT connector with 26-
30 Fr and 32-34 Fr
nasopharyngeal airways,
respectively) (Photo 27).

2. O2 flow is usually set at 4-6
L/min and the circuit pressure
relief valve is opened.  

3. To avoid trauma to
nasopharyngeal tissue, a well-
lubricated small nasopharyngeal
way (26 or 28 Fr) is gently inserted
to make sure there is no resistance
in the airway. After replacing it
with an appropriate
nasopharyngeal airway, the ETT
connector is connected to the
nasopharyngeal airway and the
breathing circuit is then
connected to the ETT connector.

4. If the reservoir bag is over-
distended, we need to adjust the
pop-off valve to ensure that O2
flow is not excessive which may
force secretion into the trachea
and/or cause tissue injury.

5. The patient may breathe
through the breathing circuit if
the nasopharyngeal airway is the
only patent airway. By adjusting
the pressure relief valve, it
provides CPAP that may prevent
airway from collapsing.  

6. If the patient is apneic because
of over-sedation, this technique
allows low positive pressure
ventilation in order to gain time
for sedation to wear off or for
turning the patient supine to
perform assisted ventilation.  

7. We are always prepared to
ventilate and oxygenate the
patient using a bag-mask or ETT if
this approach fails to improve
oxygenation quickly.

Retrobulbar Block (Photo 28-
: Tape the face tent over the
bridge of the nose and lower
cheeks for
pre-oxygenation, and
remove it
before sterilization preparation to
avoid suffocating the
patient (Photo 29)!!

Flexible Fibro-optic
Bronchoscopy (FOB)

Tape the specimen plastic sheet
on the forehead and both
cheeks. Cut a hole near the
nose or the mouth or tear the
plastic sheet to middle to allow
bronchoscope for oral (Photo
30) or nasal (Photo 31)
insertion of  bronchoscope.
Overlap and tape plastic sheets
together  to avoid O2 from

Modified TSE "Mask" to
of Combative Trauma
Patients for Emergency
Endotracheal Intubation
(Photo 32)

Since 2006, many
anesthesia attendings in the
Department of
Anesthesiology have
contributed their time and
their own financial
resources to teach the use
of these simple techniques
national and
anesthesiology meetings.
Our main goals are to
improve patient safety and
reduce healthcare costs.

Special thanks to all the
anesthesia attendings (Dept.
Anesthesiology, Rutgers (formerly
UMDNJ)RWJMS) who have
supported us with extra
time to present our clinical
findings as poster
presentations and
demonstrate this technique
as Scientific and
Educational Exhibits.  
Publications/Poster Presentations     

Please see Anesthesia Patient
Safety Foundation 5 Reviews
(2007-2010, 2013, 2014) and
Anesthesiology News Review
& 2016)
Welcome to
TSE "Mask" (Face Tent) & Nasal TSE-PAP Mask
Assembly to Improve Oxygenation & Patient
Safety in Patients during Monitored Anesthesia
Care, Awake Endotracheal Intubation and
General Anesthesia Induction
Photo 1.        Upper GI Endoscopy, FOB or TEE. With the
mouth kept open by a bite-block, a patient receives only
minimal O2 via a nasal cannula. Airway obstruction,
respiratory depression or over-sedation easily leads to
severe O2 desaturation.     
Photo 2.        Secure  the plastic sheet  with taping along the
forehead and the cheek. Tape the clear plastic sheet above
the eye and make sure eyes are closed and protected.
Photo 3.        Tape along the lower jaw.
Photo 5.        Double taping  the edge of a soft plastic sheet
to  strengthen
the face tent to avoid interfering with the scope.
Photo 4.        The rigid edges of  a zip-lock bag stand up like a
with an open door.
Photo 7.        ERCP in lateral decubitus position with pulse
oximetry, O2 and
ETCO2 tracings.
Photo 8.        ERCP in prone position.
Photo 9.        TEE, PEG or FOB in
supine position.
Photo  20.  With mouth breathing, a nasal
cannula delivers minimal O2  a
nd produces a
poor ETCO2 tracing.         
Photo 21.   Lower Body Procedures, Cardioversion or AICD
: Tape the plastic sheet  to the bridge of the nose and
cheeks or tape it  to the forehead to cover eyes, the nose and the
.  Keep the lower portion open to avoid re-breathing
Do not use a soft plastic sheet to avoid it from
collapsing and being sucked into the mouth.
Photo 22.   Upper body procedures: Tape a fluid-shield surgical
mask firmly  to the lower jaw.
Tape the sharp edges of the plastic
shield to  
"Take my picture. I want to be
famous!"  The first patient posted to
demonstrate the use of  TSE "Mask" for
upper GI endoscopy.     
Photo 23.        This modified TSE "Mask" for upper body
procedures increases FiO2 , prevents O2 pooling under the
surgical drape
and reduces the risk of FIRE HAZARDS.
Photo 28.        Pre-oxygenation for retrobulbar block.
Photo 25.        Jack-Knife or Prone Position. Use pillows
to support the upper body and head to maintain a patent
airway. Tape a large clear plastic sheet like a drape over the
head. Keep the bottom open to avoid rebreathing CO2.
Photo 6.        A plastic shield from  a fluid-shield surgical mask
Photo 10.        A plastic shield
from  a fluid-shield surgical mask
Photo 26.       A simple and quick rescue technique: An
anesthesia breathing circuit connected to a nasopharyngeal
airway using an ETT connetor in a deeply-sedated patient with
upper airway obstruction in jackknife position.
Photo 27.        An anesthesia breathing circuit is connected to a
30 Fr. Nasopharyngeal airway using a 7.0 ETT connector.
Photo 24.        This modified TSE " Mask" keeps the
surgical drapes from covering the face and O2 from
pooling under the surgical drapes.
Photo 22. FOB nasal approach
Photo 30. FOB oral approach
Photo 29. Remove it before eye
sterilization preparation to AVOID
Photo 32. Secure nasal cannula with tape, turn
O2 flow to 10 L/min and put the head in a large,
clean, clear plastic bag. Pre-oxygenate for a few
min, RSI of general anesthesia and remove the
bag before intubation.
Photo 11.         How to assemble a nasal TSE-PAP mask/circuit:
Inflate the air cushion of an infant face mask with about 10
cc  of air and secure a hook ring from a toddler mask or an
adult face mask with tape.
Photo 12. Secure the mask with head straps to
obtain a  good seal and to avoid compressing the
eyes. Connect it to the adult anesthesia breathing
circuit. Tape the nasal cannula to the lower rim of
the bite block for capnography.  
Photo 13. Pad under the straps to avoid excessive
compression pressure on the facial nerves. Cover
the mouth with a clear, clean plastic sheet (TSE
"Mask") to improve the quality of capnography.
Photo 14. A patient with OSA under deep propofol
sedation during EGD.
A nasal TSE-PAP mask is connected to an adult
breathing circuit and an anesthesia machine. The
pop-off valve is closed. Fresh O2 flow is set at 6-8
L/min. Fresh air can be added to keep FiO2 under 0.8.
Photo 15. The patient is breathing spontaneously as
indicated by the capnography obtained with an air
sampling line of  a nasal cannula.
Photo 19.       TEE at the Echocardiology Lab (no anesthesia
machine). A Nasal TSE-PAP mask connected to a mask-bag (+
PEEP valve) with a flexible extension and a wall O2 outlet (8-10
L/min O2 flow).
Photo 16. EGD with Dilation
Photo 17.   Nasal TSE-PAP
Mask/Circuit for an OSA Patient
under MAC during Colonoscopy
Photo 18. Nasal TSE-PAP mask/Circuit for an
OSA patient under MAC during Hysteroscopy and

Videos:  How to use Nasal TSE-PAP Mask/Circuit to improve oxygenation in an OSA patient under
propofol sedation during SVT Ablation  in Cath Lab
How to use Nasal TSE-PAP Mask/Circuit to improve oxygenation in an OSA patient under
remifentanil infusion during Atrial Fibrillation/Flutter Ablation  in Cath Lab
Video: How to Improve Oxygenation using
a TSE "Mask" during EGD
9 Awards including the
2008, 2013
, 2015 & 2016
PGA "Best Exhibit for
Clinical Application"
Photo 19a. Video Laryngoscopy
assisted endotracheal intubation
Photo 19b. FOB assisted endotracheal
Photo 19c. Combined video Laryngoscopy and FOB assisted
endotracheal intubation
Photo 19d. Pre-oxygenation and assisted nasal ventilation during
induction of general anesthesia in a patient with full beard.
Photo 19e. Pre-oxygenation and assisted nasal ventilation during
induction of general anesthesia in an edentulous patient .
Photo 19f-g. Pre-oxygenation and assisted nasal ventilation during
induction of general anesthesia in obese patients with poor face-mask fit.
2014 3rd Place Award for Scientific/Educational Exhibit at the ASA Annual
Meeting, New Orleans, LA, Oct 2014, (Feb 2015 ASA Newsletter, page 40-41)
& Anesthesia Patient Safety Foundation E.C. Pierce, Jr., MD, Award for "Best
Scientific Exhibit" (APSF Newsletter February 2015, page 48).