Download Bag Valve Mask (BVM) Ventilation

Clinical Skill Information Sheet
Bag Valve Mask (BVM) Ventilation
Aim
To safely and effectively ventilate patients using a bag-valve-mask
Indications
When a patient is unable to effectively self-ventilate and is at risk of hypoxia.
Background
When a patient is unable to breathe for him or herself and/or has inadequate
ventilation rate or effort, it is vital that they are ventilated with oxygen to ensure
hypoxia is avoided. A paramedic using a bag-valve-mask performs ventilations.
The Bag-Valve-Mask (BVM) is a piece of equipment that can either be reusable or
disposable. It can be used with a number of different sized masks to ensure an
adequate seal for all patients. There are a number of different sized bags to better
suit particular patients, such as adults, paediatrics and neonates. The BVM is initially
used with a basic airway: an oropharyngeal airway (OPA) but can also be attached
to advanced airway adjuncts, such as a laryngeal mask airway (LMA) or
endotracheal tube (ETT).
The BVM is often operated by one trained operator, but can also be operated by two
trained operators, which is the recommended method in all patients especially those
who are difficult to ventilate.
Bachelor of Paramedic Science
Clinical Skill Information Sheet
Objective
Manage
Safety
Prepare the
patient
Rationale
Safety is the first
priority when
managing any patient.
Action
1. Use universal precautions. Always
wear gloves and goggles when
attending to a patient.
Ensure the patient has
a clear airway and is
positioned
appropriately to be
ventilated.
2. You may also want to consider
wearing a facemask and gown.
1. Position yourself behind the head of
the patient. You may be kneeling if
they are lying on the ground or you
may be able to sit/stand behind them if
they are on furniture such as a bed,
stretcher or recliner chair. Ideally, you
want the patient’s head around waist
height.
The paramedic must
be positioned
appropriately to ensure
that the correct
technique is utilised
and ventilation is
effective.
Ensuring equipment is
in working order is
essential to providing
adequate ventilation to
a patient.
Prepare the
equipment
2. Ensure the patient’s airway is clear.
(See Basic Airway Management –
Information Sheet)
1. Ensure all parts of the BVM are
securely attached in the appropriate
manner. See relevant manufacturer’s
instructions for this.
Correct mask selection
is essential to ensure
an effective seal can
be gained and
maintained during
patient ventilation.
The amount of air in
the rim of the mask
can be adjusted using
a syringe to
accommodate different
face shapes.
2. Select the appropriate sized mask for
the patient. This will be determined by
the size of the patient’s face. Ensure
the mask can encapsulate the patient’s
mouth and nose.
Bachelor of Paramedic Science
Clinical Skill Information Sheet
Objective
Correct hand
positioning
(single
operator)
Rationale
The maximum oxygen
flow rate is required to
ensure adequate
inflation of the
reservoir bag and
appropriate oxygen
pressures.
Action
The maximum flow
setting for a particular
oxygen cylinder will be 3. Attach the oxygen tubing to the BVM
dependent on the flow
using the designated port.
gauge. Commonly, this
is 15 L/min for a C4. Dial the oxygen up to its maximum
sized cylinder, and
setting.
25L/min for a D-sized
cylinder.
5. Ensure the reservoir bag inflates
completely before applying assembled
unit to patient.
Using the “C-E” grip to 1. Position yourself at the head of the
hold the patient’s face
patient.
up and into the mask
will ensure that
2. With one hand, use your thumb and
occlusion of the airway
forefinger to make the shape of the
is avoided.
letter C. Your remaining three fingers
will naturally form the shape of the
letter E. Below is an effective C-grip.
It is essential to ensure
a patent airway at all
times so that
obstruction to airflow is
minimised.
There are a number of
hand positions that are
effective, due to the
size of the mask used
and the operator’s
hands. As long as a
good seal around the
face and an open
airway are maintained,
something comfortable
and sustainable for
you is ideal.
3. Use this grip to hold the back of the
facemask firmly.
Bachelor of Paramedic Science
Clinical Skill Information Sheet
Objective
Rationale
Action
4. Position the top of the mask at the top
of the patient’s nose.
5. Simultaneously lower the mask to the
patient’s face whilst using your three
fingers to pull their face up and into the
mask. Ensure your fingers are holding
on to the patient’s mandible and not
the soft underside of their chin. You
will need to continue applying an
upwards pressure everytime you
ventilate the patient.
Although it is often
necessary in the
prehospital setting for
a single operator to
ventilate a patient with
the BVM due to
limitations of
resources, it is best
practice to use a twohanded technique to
hold the mask. This
ensures an effective
seal is maintained.
Correct hand
positioning
(two
operator)
6. Ensure a good seal by listening for air
leaks.
1. Position yourself at the head of the
patient.
2. Either use a CE grip with both hands to
hold the back of the mask, as shown
below.
OR use a modified CE grip by placing
both of your thumbs either side of the
back of the mask, as shown below.
3. Position the top of the mask at the top
of the patient’s nose.
Bachelor of Paramedic Science
Clinical Skill Information Sheet
Objective
Rationale
Action
4. Simultaneously lower the mask to the
patient’s face whilst using your fingers
to pull their face up and into the mask.
Ensure your fingers are holding along
the patient’s jaw and not the soft
underside of their chin. You will need
to continue applying an upwards
pressure everytime you ventilate the
patient.
5. Ensure a good seal by listening for air
leaks.
It is imperative that the
1. Using your spare hand (or getting
correct technique is
someone else if you are using the 2utilised as the delicate
operator technique) hold the selfairways and lungs can
inflating bag and gently and smoothly
be damaged if lung
squeeze it in one fluid motion until your
volumes are exceeded or
fingers touch. Ensure this process
ventilations are too
occurs over about 1 -1.5 seconds. This
forceful.
will mean the bag has been fully
compressed.
Some of the BVM’s have
pressure relief (blow-off)
valves to protect from
overzealous ventilation,
however these devices
should not be relied upon
and correct technique
should always be the
clinician’s main aim.
Correct
ventilation
technique
The bag should be easy
to squeeze, with minimal
effort required.
Sometimes the patient’s
physiological state will be
the cause of the
difficulty, e.g.
bronchoconstriction. In
this instance, extra care
must be taken to not
over-ventilate the patient
and allow for a prolonged
expiratory phase.
Most adult self-inflating
bags come in volumes from
1200-1600mL. They should
only need compression of
approx.1/3 to achieve
adequate ventilation for an
adult tidal volume
(~500mL).
2. Release your grip completely and
allow the bag to self-inflate fully.
3. If you find it very difficult or hard to
squeeze the bag, then there may be
an obstruction in the airway. Ensure
you are performing the correct grip and
holding the patient’s face up and into
the mask. If this does not solve the
problem then check the airway again
for obstructions, you may need to use
an advanced assessment tool for this,
e.g. laryngoscopy.
4. If the bag does not self-inflate after
delivering a ventilation ensure that the
equipment is attached correctly and that
the oxygen is freely flowing through the
device at an appropriate rate.
Bachelor of Paramedic Science
Clinical Skill Information Sheet
Objective
Correct
ventilation
rate
Measure
effectiveness
Rationale
The rate of ventilation
will be dependent on
the patient’s condition.
In most instances
returning the patient to
within normal oxygen
saturation levels is the
aim.
Action
1. Cardiac Arrest – follow the
resuscitation algorithm dependent on
the airway adjunct device in use (i.e.
OPA, LMA, ETT). With a basic airway
in situ, and a compression: ventilation
ratio of 30:2, you should be providing
two ventilations about every 18
seconds.
A normal healthy
person will breathe
between 12-20
respirations per
minute.
2. Assisted ventilations – when assisting
with ventilations using the BVM, you
may need to fully ventilate the patient
as explained above. In this case, aim
to provide one ventilation every 5
seconds. Sometimes the patient may
be breathing at a sufficient rate, but the
depth is inadequate. In which case you
need to squeeze the bag a little to
provide extra oxygen with each breath
they take. Time it so that you squeeze
the bag as they inhale. You will feel
that it is relatively easy to push the air
into their airways. If you attempt to do
it as they are exhaling, you will feel
significant resistance and you will hear
air escaping through the sides of the
mask, or the relief valve.
1. If the patient is apnoeic and you are
ventilating by squeezing the bag,
watch for rise and fall of the patient’s
chest. This will give you a clear
indication of whether the oxygen is
getting into their lungs. Sometimes it is
difficult to see rise and fall of the
patient’s chest due to their anatomy.
It is important to
periodically confirm
that air is entering the
lungs and not the
stomach by having a
colleague listen with a
stethoscope.
The patient’s skin
colour and oxygen
saturation
measurements are
also indicators for the
effectiveness of the
ventilation.
2. Have a colleague use a stethoscope to
auscultate the patient’s chest to ensure
adequate air entry.
Bachelor of Paramedic Science