Manual Resuscitators.txt

resuscitator bags, manually operated resuscitators, hand ventilators, hand operated emergency ventilators, and bag-valve mask units (and ambu-bag, which is a brand name)

portable, hand-held devices that provide a means of delivering positive pressure to a patient�s airway delivering oxygen, air, and air/oxygen mixtures

by the type of nonrebreathing valve used

spring loaded mechanism and those relying on diaphragm valves. The diaphragm valves are further subdivided into duckbill or fishmouth and leaf type of valves

• - have a disk or ball attached to a spring. When the bag is compressed a spring pushes a disk or ball against an exhalation port occluding it, and gas is directed to the patient�s airway
• - Once the flow from the bag stops, the exhalation port opens, and gas exhaled by the patient is vented to the atmosphere. At the same time, as gas enters the self-inflating bag through the one-way gas inlet valve

When the bag is compressed the positive pressure pushes up on the leaf valve allowing gas to the patient while blocking exhalation. During exhalation, as the bag reexpands, the negative pressure pulls the leaf away from the exhalation ports and the patient is allowed to exhale to atmospheric. Exhaled gas cannot enter the bag

• - Compression of the bag pushes a diaphragm against the exhalation ports. At the same time, the duckbill valve is pushed open and gas flows to the patient. Once the flow from the bag ceases, the duckbill valve closes, and the diaphragm is pushed away from the exhalation port. Exhaled gas can then exit through the exhalation ports.
• - The spontaneous breathing patient can pull open the duckbill to receive gas from the bag.

• 1. CPR, both in and out of the hospital
• 2. Manual hyperinflation with high concentrations of O2; such as before and after suctioning.
• 3. During transport of critically ill patients.
• 4. Ventilator patients; any time they need to be off the ventilator such as during transport, medical procedures, ventilator tubing change, etc.
• 5. Stand-by for any procedure that may lead to respiratory arrest.
• 6. Coughing patients

• 1. Have no pressure-relief valve for adults and children; infant devices must incorporate an in-line manometer.
• 2. Have a bag volume of approximately 1,600 ml for adults and children, and approximately 500 ml or less for infants.
• 3. Have minimal forward and back leak.
• 4. Have a standard patient valve connector of 15:22 mm (ID:OD).
• 5. Be impossible to misassemble.
• 6. Be easily sterilized or for single patient use.
• 7. Provide for measurement of exhaled tidal volume.
• 8. Be capable of providing an FDO2 of 1.0 even when large volumes are delivered.
• 9. Provide some indication that supplemental oxygen is being supplied (easily ascertained with bag reservoir but difficult with tube-type reservoir).
• 10. Be capable of being restored to proper function after being disabled with an obstruction (e.g. vomitus) within 20 sec.
• 11. Be able to be restored to proper function after being dropped from a height of 1 meter onto a concrete floor.
• 12. Be designed so that pressure generated at the patient connection port is less than 5 cm H2O during exhalation (at a flow of 5 L/min for patients weighing <10 kg and 50 L/min for all others).
• 13. Be designed so that pressure generated at the patient connection port does not exceed -5 cm H2O during inspiration (at a flow of 5 L/min for patients weighing <10 kg and 50 L/min for all others).
• 14. Be capable of providing a high FDO2 during spontaneous breathing with low inspiratory and expiratory resistance.

• 1. Allow for a tight seal.
• 2. Provide minimal internal dead space.
• 3. Have a clear mask body.
• 4. Be available in a variety of sizes.

• 1. Weight: it should be lightweight.
• 2. Dimensions: it should be easily held in one hand.
• 3. Positive end expiratory pressure (PEEP) capability: the device should allow a PEEP valve to be attached at the exhalation port.
• 4. Self reinflation time: the bag construction should allow for rapid refill so faster respiratory rates can be achieved as necessary.
• 5. Maximum cycling rate (see 4)
• 6. Number of parts: the device should be easy to disassemble, clean, and reassemble. This is easier to do with fewer parts.
• 7. It should be made of durable material, nondistorting.

• 1. Using the highest acceptable oxygen flow rate to the bag.
• 2. Adding a reservoir for oxygen collection.
• 3. Utilizing the longest possible bag refill time.
• 4. By attaching an oxygen blender in-line with the gas source

• - Plastic bags: advantage can easily monitor the adequacy of the flow rate
• - Aerosol hose: 5-inch flex hose can only hold 50 mL of volume, so it is ok for infants to have at least 15 inches. The reservoir needs to be wider not longer for adults

• - Cardiac Arrest
• - Myocardial infarction, life-threatening arrhythmia, hypovolemic shock, severe infections such as septic shock.
• - Respiratory arrest
• - Spinal cord or head injuries, drug overdose, pulmonary edema, anaphylaxis, smoke inhalation & high risk delivery (usually leads to hypovolemic shock)

• Vital sign deterioration
• Loss of consciousness
• Arterial blood gas value deterioration
• Non-emergency use of the manual resuscitator:Increased breaths prior to invasive procedures such as suctioning the tube
• Backup ventilation in case of power failure
• Transporting a patient who is on mechanical ventilation
• Deep breaths to sigh a patient who is breathing shallowly on his own

• - The only contraindications to bagging is When it is known that the patient has a signed & witnessed DO NOT RESUSCITATE [DNR] on her chart.
• - CPR has been determined to be futile because of the terminal nature of the patient

• 1. Unrecognized equipment failure
• 2. Gastric distention with mask ventilation.
• 3. Pulmonary barotrauma/volutrauma

occlude the patient side of the nonrebreathing valve outlet and vigorously try to compress the bag. If the inlet and outlet valves are in place and properly working, you will encounter a strong resistance to compression and no gas will leak out of the bag

• 1. A rapid and dramatic decrease in the pressure required to compress the bag (usually signaling oxygen inlet valve failure)
• 2. An inability of the patient to fully exhale (indicating a jammed or malfunctioning nonrebreathing patient valve).

providing low to moderate inspiratory flows. With an adult, this means using a full 2 seconds to deliver the tidal volume. A cuffed endotracheal tube is the best method of avoiding this problem

• - It is with the small child and infant that barotrauma/volutrauma problem lies. An adult resuscitator should never be used on a small child or infant. Even pediatric units with larger volumes (500 ml or greater) should not be used on the small child or infant.
• - The best preventative to high pressures is to place a pressure manometer in line and read it.

• - Oxygen-powered resuscitators are manually triggered valves that are powered by compressed oxygen (50 psi)
• - The practitioner provides ventilation by pressing the actuator button or trigger while gauging its adequacy by observing chest movement. Some of these devices may also be activated by the patient generating negative pressure, demand valves. Exhalation is passive through a venting port.

• 1. Robert Shaw demand valve
• 2. Hudson Elder valve

• 1. Provide a constant flow of 100% oxygen at less than 40 L/min
• 2. Limit inspiratory pressure to 60 cm H2O via a relief valve
• 3. Allow inspiratory pressure limit up to 80 cm H2O (under medical direction)
• 4. Sound an audible alarm whenever the relief valve is activated
• 5. Operate under common environmental conditions
• 6. Provide demand flow without increasing work of breathing
• 7. Have a standard 15:22 coupling for airways and attachments
• 8. Rugged, break-resistant, compact, and easy to hold
• 9. Trigger positioned so that both hands of the rescuer can remain on the mask to hold it in position

• 1. Can deliver 100% oxygen
• 2. If device is a demand valve, then patient can breathe spontaneously at 100% oxygen.

• 1. If primary diaphragm ruptures, gas at 50 psig will be delivered to the patient (will not pressure limit)
• 2. Patient will not receive enough volume, if ventilating pressures needed exceed the pressure limit of the device

• - inflates only when air or oxygen from a compressed gas source is forced into them. It requires a well modulated flow of gas into the inlet port, correct adjustment of the flow control valve and careful attention to a tight seal at the face mask. A port with an attached pressure gauge must be present to monitor ventilatory pressures.
• - Oxygen flowing into the reservoir inflates it when the tail of the bag is pinched closed. When the bag is manually compressed, a breath is delivered to the patient. When it is released, the exhaled gas flows out through the tail of the bag.

• - blood backs up into the lung, the lung gets stiffer [compliance] and it takes more pressure to send in the same volume
• - RCP must apply more pressure to the bag to get the same volume into the patient�s lungs as the lung�s compliance with your efforts decreases
• - As the lung�s airway resistance [RAW] increases due to secretions, other obstructions or bronchospasm, again the pressure used to inflate the lung may have to be increased

• 1. Vary in size from 500 to 2,000 ml.
• 2. Inflated by a controlled gas source.
• 3. Variable flow outlet.
• 4. Conform to the same standards for self inflating resuscitators, where appropriate.
• 5. Monometer placed inline, especially for infants.

• 1. Can deliver precise FIO2 (can guarantee 100% oxygen when used with oxygen source).
• 2. Can deliver a wide range of PEEP.
• 3. Can control peak inspiratory pressure.

• 1. Can deliver dangerously high pressures to a patient.
• 2. Not enough flow, patient will rebreathe their own gas.
• 3. Not enough flow, patient will not get adequate ventilatory volume

• Flow inflated bags have the disadvantage of always needing an adequate flow rate of gas to work
• They have the advantage of being the easiest bag to feel changes inside the patient
• Excessively high flow rates through the flow-inflated bags can raise the PEEP inadvertently
• If the patient interface slips off the self-inflated bag, it will require a little time to re-inflate
• The flow-inflated bag can deliver drugs
• The self-inflated bag has less parts to malfunction or lose

• Flow inflated bags have the disadvantage of always needing an adequate flow rate of gas to work
• They have the advantage of being the easiest bag to feel changes inside the patient
• Excessively high flow rates through the flow-inflated bags can raise the PEEP inadvertently
• If the patient interface slips off the self-inflated bag, it will require a little time to re-inflate
• The flow-inflated bag can deliver drugs
• The self-inflated bag has less parts to malfunction or lose

pg. 315

• 1. No leftover parts
• 2. Air only exits through pt's valve on inspiration
• 3. Exhalation valve and tail valve close
• 4. Bag refills quickly on expiration

• - Use of oxygen source
• - Increased oxygen flow
• - Add reservoir
• - Allow slower refill

• - Use increased Vt
• - Increased rates
• - Inspiratory hold

• Adults: Gastric insufflation, barotrauma, facial necrosis, spinal cord injury, hypo/hyperventilation, vomiting/aspiration
• Neonates: Similar

Neonatal vent requires increased rates, decreased volumes, decreased pressures, head tilt not hyper extended but more in neutral position

• 1. adequate chest rise and fall
• 2. bilateral equal breath sounds
• 3. Colormetric capnography (CO2 monitor)
• 4. ABG

• Mask: Availability of proper size, ability to adequate seal, pressure increased above 25 cmH20 tend to cause gastric distension. Pressures and volumes one can achieve limited to size and design of bag short term use.
• Artificial Airway: ability maintain seal with airway cuff, resistance due to tube size, and skill of RCP.

- decreased compliance and increased resistance will both decrease volumes and increase pressures

• A. Normal compliance, normal resistance
• - drug overdose without aspiration
• - post-op with no pulmonary history
• B. Increased compliance, decreased resistance
• - COPD without airway obstruction
• C. Increased compliance, increased resistance
• - COPD with airway obstruction or small ET tube
• D. Decreased compliance, increased resistance
• - Atlectasis, pneumonia, ARDS, most restrictive disorders, CHF with bronchospasm, secretions in airway, mucosal edema and inflamation, small ET/trach tube
• E. Decreased compliance, decreased resistance
• - Atlectasis, pneumonia, ARDS, most restrictive disorders, CHF without airway involvement