Mechanical Ventilation for NursingMelissa Dearing, BS, RRT-NPS, RCPAssociate Professor of Respiratory Care

Curtis Shelley, BS, RRT-NPS, RCPRespiratory Educator Hermann Childrens Hospital

Indications for Mechanical Ventilation Airway Compromise airway patency is in doubt or patient may be at risk of losing patency

Indications for Mechanical VentilationRespiratory Failure 2 Types

Hypoxemic Respiratory Failure

Hypercapnic Respiratory Failure

Hypoxemic Respiratory Failure

PaO2 < 60 mmHg in an otherwise healthy individual

Hypercapnic Respiratory FailurePaCO2 > 50 mmHg in an otherwise healthy individualAKA Ventilatory FailureCaused by increased WOB, ventilatory drive, or muscle fatigue

Indications for Mechanical VentilationNeed to Protect the Airway

For some reason the patients ability to sneeze, gag or cough has been dulled and aspiration is possible.

Contraindications for an Artificial Airway

When a pts desire to not be resuscitated has been expressed and is documented in the pts chart

Establishing an Artificial Airway Adult female 8.0 Adult male 9.0

Miller vs. MacIntosh Blades

Intubation ProcedureCheck and Assemble Equipment:

Oxygen flowmeter and O2 tubingSuction apparatus and tubingSuction catheter or yankauerAmbu bag and maskLaryngoscope with assorted blades3 sizes of ET tubesStyletStethoscopeTapeSyringeMagill forcepsTowels for positioning

Intubation ProcedurePosition your patient into the sniffing position

Intubation ProcedurePreoxygenate with 100% oxygen to provide apneic or distressed patient with reserve while attempting to intubate.

Do not allow more than 30 seconds to any intubation attempt.If intubation is unsuccessful, ventilate with 100% oxygen for 3-5 minutes before a reattempt.

Intubation Procedure Insert Laryngoscope

Intubation Procedure

Intubation Procedure

After displacing the epiglottis insert the ETT.

The depth of the tube for a male patient on average is 21-23 cm at teethThe depth of the tube on average for a female patient is 19-21 at teeth.

Intubation Procedure

Confirm tube position:

By auscultation of the chestBilateral chest riseTube location at teethCO2 detector (esophageal detection device)

Intubation Procedure Stabilize the ETT

Intubation Procedure Video on Intubation:

http://youtube.com/watch?v=eRkleyIJi9U&feature=related

Mechanical Ventilators

Different Types of Ventilators Available:

Will depend on you place of employment

Mechanical Ventilators

Mechanical Ventilators

Mechanical Ventilators

Mechanical Ventilators

Mechanical Ventilators

High Frequency Mechanical Ventilator

Ventilator Settings Terminology

A/C: Assist-ControlIMV: Intermittent Mandatory VentilationSIMV: Synchronized Intermittent Mandatory VentilationBi-level/Biphasic: Non-inversed Pressure Ventilation with Pressure Support (consists of 2 levels of pressure)

Ventilator Settings Terminology (cont)

PRVC: Pressure Regulated Volume Control PEEP: Positive End Expiratory PressureCPAP: Continuous Positive Airway PressurePSV: Pressure Support VentilationNIPPV: Non-Invasive Positive Pressure Ventilation

VOLUME vs. PRESSURE VENTILATION

Volume ventilation: Volume is constant and pressure will vary with patients lung compliance.Pressure ventilation: Pressure is constant and volume will vary with patients lung compliance.

MODES of VENTILATION

Control Mode

Delivers pre-set volumes at a pre-set rate and a pre-set flow rate.The patient CANNOT generate spontaneous breaths, volumes, or flow rates in this mode.

Control Mode

Assist/Control Mode

Delivers pre-set volumes at a pre-set rate and a pre-set flow rate.The patient CANNOT generate spontaneous volumes, or flow rates in this mode. Each patient generated respiratory effort over and above the set rate are delivered at the set volume and flow rate.

A/C cont.Negative deflection, triggering assisted breath

Delivers a pre-set number of breaths at a set volume and flow rate.Allows the patient to generate spontaneous breaths, volumes, and flow rates between the set breaths.Detects a patients spontaneous breath attempt and doesnt initiate a ventilatory breath prevents breath stackingSYCHRONIZED INTERMITTENT MANDATORY VENTILATION (SIMV):

SIMV cont.Machine BreathsSpontaneous Breaths

PRESSURE REGULATED VOLUME CONTROL (PRVC):This is a volume targeted, pressure limited mode. (available in SIMV or AC)Each breath is delivered at a set volume with a variable flow rate and an absolute pressure limit.The vent delivers this pre-set volume at the LOWEST required peak pressure and adjust with each breath.

PRVC

POSITIVE END EXPIRATORY PRESSURE (PEEP):This is NOT a specific mode, but is rather an adjunct to any of the vent modes.PEEP is the amount of pressure remaining in the lung at the END of the expiratory phase.Utilized to keep otherwise collapsing lung units open while hopefully also improving oxygenation.

PEEP cont.PEEP is the amount of pressure remaining in the lung at the END of the expiratory phase.Pressure above zero

Demonstration of PEEPhttp://youtube.com/watch?v=oKH7CtsEgHw

Continuous Positive Airway Pressure (CPAP):This IS a mode and simply means that a pre-set pressure is present in the circuit and lungs throughout both the inspiratory and expiratory phases of the breath.CPAP serves to keep alveoli from collapsing, resulting in better oxygenation and less WOB.The CPAP mode is very commonly used as a mode to evaluate the patients readiness for extubation.

HIGH FREQUENCY VENTILATION

Comparison of HFOV& Conventional VentilationDifferencesCMVHFOV

Rates0 - 150180 - 900Tidal Volume4 - 20 ml/kg0.1 - 3 ml/kgAlveolar Press0 - > 50 cmH2O0.1 - 5 cmH2OEnd Exp VolumeLowNormalizedGas FlowLowHigh

OxygenationOxygenation is primarily controlled by the Mean Airway Pressure (Paw) and the FiO2.Mean Airway Pressure is a constant pressure used to inflate the lung and hold the alveoli open.Since the Paw is constant, it reduces the injury that results from cycling the lung open for each breath

Video on HFOV

http://youtube.com/watch?v=jLroOPoPlig

Initial SettingsSelect your mode of ventilationSet sensitivity at Flow trigger modeSet Tidal VolumeSet RateSet Inspiratory Flow (if necessary)Set PEEPSet Pressure LimitHumidification

Post Initial SettingsObtain an ABG (arterial blood gas) about 30 minutes after you set your patient up on the ventilator.An ABG will give you information about any changes that may need to be made to keep the patients oxygenation and ventilation status within a physiological range.

ABGGoal:Keep patients acid/base balance within normal range:

pH 7.35 7.45PCO235-45 mmHgPO280-100 mmHg

TROUBLESHOOTING

TROUBLESHOOTINGAnxious Patient

Can be due to a malfunction of the ventilatorPatient may need to be suctionedFrequently the patient needs medication for anxiety or sedation to help them relax

Attempt to fix the problem Call your RT

Low Pressure AlarmUsually due to a leak in the circuit.

Attempt to quickly find the problemBag the patient and call your RT.

High Pressure AlarmUsually caused by: A blockage in the circuit (water condensation)Patient biting his ETTMucus plug in the ETT

You can attempt to quickly fix the problem Bag the patient and call for your RT.

Low Minute Volume AlarmUsually caused by:Apnea of your patient (CPAP)Disconnection of the patient from the ventilator

You can attempt to quickly fix the problem Bag the patient and call for your RT.

Accidental ExtubationRole of the Nurse:

Ensure the Ambu bag is attached to the oxygen flowmeter and it is on!Attach the face mask to the Ambu bag and after ensuring a good seal on the patients face; supply the patient with ventilation.

Bag the patient and call for your RT.

OTHERAnytime you have concerns, alarms, ventilator changes or any other problem with your ventilated patient.

Call for your RTNEVER hit the silence button!

***Once the need for an artificial airway has been established you must select the appropriate size ETT for the patient. The largest tube that will fit into the airway should be used. The smaller the tube the harder it is for the patient to breathe. Just a reduction of 16% of the radius of an ETT will double the WOB for the patient.Another thing to consider is what type of blade to use for the intubation.*Miller Blade is straight directly lifts the epiglottis to allow visualization of the vocal cords.MacIntosh blade is curved; inserted into the vallecula to indirectly lift the epiglottis.Infants are always intubated with the Miller die to the floppy airway.****Laryngoscope is always held in the left hand and is used to displace the tongue to the left so that the epiglottis may be seen.*Laryngoscope is always held in the left hand and is used to displace the tongue to the left so that the epiglottis may be seen.*An easy trick to use is tube size X 3 works almost all the time.*You must rule out an esophageal intubation with capnography or by BS. Always listen over the epigastrium after listening to the chest. These are bedside procedures that must be done immediately after intubation prior to an XRAY.*Can be done with tape or a commercially available ETT stabilizer.Always tape above the ETT and never to the chin.****************Notice how the patients breath reflects the ventilator breath. Not for conscious patients!**Please note that the patient has to be spontaneously breathing to use this mode! Often used in conjunction with weaning the patient from the ventilator.*Used for patients that cannot be oxygenated.*This is the primary reason for using a HFV.*9 minute video I just want to show how the oscillator sounds and what it looks like.*Flow Trigger allows the patient to pull a spontaneous breath from the vent whenever he wants.Tidal Volume is the amount of air the patient is given with each breath (10-12 ml/kg IBW)Rate is normally set at 10-12 bpm (adults) and then changed via ABGFlow most new vents set the flow to deliver a set I:E ratio. Flow of 40-80 L/min to achieve an I:E of approximately 1:2.PEEP 3-5 cmH20 is physiologic peepPressure Limit set at 10 20 cmH20 above pts own PIPHumidification heated to 35-37C to provide humidification due to bypassed upper airways**Any variance in these values will require a change made to this patients ventilator.