|How to Improve Oxygenation and Patient Safety by
an Ineffective Nasal Cannula to
a 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 Reviews
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
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
EGD, EUS, ERCP, PEG,
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
O2 (<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
ASGE Guideline: Adverse Events of Upper GI
Endoscopy, BSG Guidelines in Gastroenterology:
Complications of GI Endoscopy and SGNA Risks
We have used a simple plastic sheet
to convert an ineffective nasal
cannula to a face tent since 2001
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
tape. (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
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.
When we use a plastic shield from
a fluid-shield surgical mask, we
tape the plastic sharp edges to
avoid corneal abrasion.
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
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
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
a tent-like position with an open door,
we can avoid re-breathing of CO2
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
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,
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
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
ventilation can be
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 (firstname.lastname@example.org)
It improves oxygenation
and can be used to pro-
desaturation in obese
patients with OSA.
( Please see Publications #70 & 71,
(Patients consented for
This nasal mask assembly
has also been used for
awake FOB and/or video
(Photo 19a-c) and
preoxygenation and assisted
nasal ventilation for
patients with poor face-
mask fit during induction of
general anesthesia (Photo
(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
to avoid high O2
under the surgical drapes.
Taping a fluid-shield surgical
mask firmly to the lower jaws will
decrease the risk of FIRE
HAZARDS. (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
covering the patient's face.
It is very important to
protect the eyes. Tape the
sharp edges of the plastic
shield to avoid corneal
abrasion. (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
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
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
Retrobulbar Block (Photo 28-
29): Tape the face tent over the
bridge of the nose and lower
pre-oxygenation, and remove it
before sterilization preparation to
avoid suffocating the
patient (Photo 29)!!
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
Since 2006, many
anesthesia attendings in the
contributed their time and
their own financial
resources to teach the use
of these simple techniques
at national and
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
demonstrate this technique
as Scientific and
Please see Anesthesia Patient
Safety Foundation 5 Reviews
(2007-2010, 2013, 2014) and
Anesthesiology News Review
(2009 & 2016)
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