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AVEA Enhanced Pulmonary Mechanics. Advanced Settings User Interface Module. Advanced Settings Feature. Accessing Advanced Features. Press “Adv Settings” hard key on left side panel of the Avea monitor to access the Advanced Settings Window. Advanced Settings Window.
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Advanced SettingsUser Interface Module Advanced Settings Feature
Accessing Advanced Features Press “Adv Settings” hard key on left side panel of the Avea monitor to access the Advanced Settings Window
Advanced SettingsWindow Yellow triangle indicates this parameter has Advanced Settings
Activating an Advanced Setting Press the desired parameter. The parameter will then be high-lighted with a blue background. The Advanced Settings features will then appear in the window above for the parameter
Advanced Settings Universal Features: Sensitivity & Pressure Support
Sensitivity: Flow & Pressure Flow Trigger Advanced Settings Bias Flow Pressure Trigger Sensitivity
Sensitivity • “Bias Flow” • Bias Flow enables Flow Triggering • To have adequate Flow Triggering, the Bias Flow should be set 0.5 liters above the Flow Trigger setting • Example: Bias Flow set at 2.0 litres, Flow Trigger should be set no higher than 1.5 litres • “Pressure Trigger” • The Avea has both a pressure and a flow trigger active at the same time. Whichever signal (flow or pressure) is triggered first, the ventilator will then cycle into inspiration
Pressure Support Ventilation PSV Setting has 4 Advanced Settings Max Inspiratory Time Volume Limit Rise Time Flow Cycle %
Pressure Support Ventilation • “Volume Limit” • Every pressure type breath on the Avea has “Volume Limit” as an Advanced Setting feature • The clinician can enter a maximum volume limit. Once the ventilator has reached this limit during the delivery of the breath, it will then cycle the breath to exhalation using volume as the cycle criteria • When the volume limit is reached, a visual display appears in the alarm area. The display remains illuminated as long as the volume limit is active • “PSV Rise Time” • Setting range is from 1 to 9, 1 being fastest and 9 slowest. • Allows the clinician to adjust the speed at which flow is delivered to the patient during a Pressure Support breath
Pressure Support Ventilation • “PSV Flow Cycle %” • The Flow Cycle works as a percentage of the peak flow of the PSV breath • The Flow Cycle can be set in increments of 5% up to 45% • Example: If the flow cycle is set at 10% and the peak flow for the PSV breath is 60 lpm, the breath will cycle when the decelerating inspiratory flow curve decays to 6 lpm • “PSV Tmax” • The PSV Maximum Inspiratory Time setting allows for an adjustable back up inspiratory time setting in circumstances where flow cycling is unreliable (i.e. endotracheal tube leaks) • PSV Tmax should be set at 1.5-2 X the set Inspiratory Time for Control breaths • The PSV Tmax is adjustable from 0.2 to 5.0 seconds
Advanced Settings Pressure Control Ventilation - PCV
PCV - Pressure Control Inspiratory Pressure Inspiratory Time Flow Trigger
Machine Volume Volume Limit Inspiratory Rise Time Inspiratory Pressure in PCV Touch Insp Pres and these settings become available
Advanced Settings Inspiratory Pressure in PCV • “Mach Vol” (Machine Volume) • This feature allows the clinician to set a target tidal volume during a Pressure Control breath • When Machine Volume is active, the “Mach Vol” icon appears in the modes display window Machine Volume icon
Machine Volume • Is a Dual Control Mode; Ventilator delivers Volume Controlled Flow signal and Pressure Control signal to gas delivery system simultaneously. • Sets the minimum tidal volume delivered from the ventilator in a pressure control breath. • Always used with the time cycling criterion in pressure control ventilation. • Circuit compliance compensated in adult and pediatric applications.
Allows for the maintenance of traditional Volume Control Ventilation while allowing the ventilator to vary peak flow to meet the patient’s inspiratory flow demands Incorporates a decelerating/ variable inspiratory flow waveform Can be thought of as a variable flow-volume ventilation Machine Volume
Ventilator calculates the decelerating inspiratory flow required to deliver the Machine Volume (Minimum Tidal Volume) in the set inspiratory time. When Peak Flow decelerates to this calculated peak inspiratory flow If Machine Volume has not been delivered transition to a continuous flow until the Machine Volume has been delivered Inspiratory Time will remain constant maximum Peak Inspiratory Pressure is determined by the High Peak Pressure alarm setting If the Machine Volume is met or exceeded during delivery of the pressure control breath, the ventilator will complete the breath as a normal Pressure Control breath. Machine Volume
Pressure Control- Volume Control Transition Pressure is increased within the breath The constant, square wave flow continues until the pre-set tidal volume is delivered
Pressure Control Decreased Compliance Lung Chest Wall Neuromuscular Blockers Increased AW Resistance Mucous Bonchospasm Pressure Control Increased Compliance Lung Chest Wall Spontaneous Breathing Decreased AW Resistance Post Suctioning Post Bronchodilators Pressure Control Adjustments with Machine Volume Guarantee
Machine Volume Note Inspiratory Pressure set at zero, breath is decelerating flow pressure controlled breath. (Set Mach Volume 350cc) Inspiratory time is constant
Machine Volume Note transitions in flow between Pressure Control and Volume Control flow waveforms
Machine Volume Vs. PRVC Machine Volume can respond to changes in compliance within 2-4 msec. PRVC will update on next breath. Compliance decreases ventilator responds within the breath Compliance increases ventilator responds within the breath
Inspiratory Pressure in PCV • “Vol Limit” (Volume Limit) • This feature allows the clinician to set a maximum volume limit that cannot be exceeded during a Pressure Control breath • When the volume limit is reached, a visual display appears in the alarm area. The display remains illuminated as long as the volume limit is active • “Insp Rise” (Inspiratory Rise Time) • Setting range from 1 to 9, 1 being fastest and 9 slowest. • Allows the clinician to adjust the speed at which flow is delivered to the patient during a Pressure Control breath
Active in: Pressure, PRVC Vsync TCPL PSV breaths only. Neonatal applications Volume LimitTM requires the use of a wye flow sensor. If a proximal flow sensor is used Volume Limit is activated by the inspiratory tidal volume measured by the wye flow sensor. If Volume Limit threshold has been reached: Alarm status indicator will change to yellow and display the words Volume Limit. Cannot be reset until the ventilator has delivered a breath, which does not meet the Volume Limit threshold. To reset the alarm status window use the alarm-reset button Do not use with leaky ET tube Volume Limit
Volume limit with Neonatal Flow Sensor 2 KG Inspiratory VT limit 16 ml = 8 cc/kg Volume limit can be used in conjunction with Machine volume to allow volume bracketing in Pressure Control. Machine volume is the minimum volume guarantee and Volume Limit will terminate the breath based on a maximum inspiratory tidal volume threshold. When used with only PCV, as compliance improves, so will volume. Patient will be protected from inadvertent volutrauma. Volume Limit may limit gas flow during hiccups or during increased flow demands of the patient.
Inspiratory Time in PCV “Flow Cycle” is the only Advanced Setting feature for Inspiratory Time.
Inspiratory Time in PCV • “Flow Cycle” • In addition to time cycling in PCV, the Avea allows the clinician the ability to add flow cycling to the inspiratory cycle criteria of the PCV breath • The Flow Cycle works as a percentage of the peak flow of the PCV breath (mimicking a Pressure Support Breath) • When a Flow Cycle percentage is set, the PCV breath can either be cycled into expiration by the percentage of Flow Cycle or Inspiratory Time depending on which criteria is met first
Breath termination at 45% 100 50 Breath termination at 5% Flow Cycle • The default setting is 0 (off) • Can be set in increments of 5% to 45% • Flow cycle can be more comfortable for spontaneously breathing patients • It can reduce mean airway pressure and VT
Flow Cycle • Allows patient to determine their own I- time by terminating the breath once a certain percentage of the peak inspiratory flow is met • May improve preload and eliminate V/Q mismatching • Improves patient/ventilator dsy-synchrony • May tremendously improve oxygenation and ventilation in spontaneously breathing patients
Peak Inspiratory Flow 40% 20% 5% Expiratory Flow Cycling V T
Fixed Inspiratory Time No Flow Cycle Flow Cycle On Flow Cycled Breath
Flow Cycle Volume Cycled Breath Flow Cycled Breath If Flow Cycle is set with Machine Volume the breath will not Flow Cycle unless the Machine Volume (Minimum Tidal Volume) has been delivered
Patient Comfort • Dial in a Flow Cycle % • May apply Flow Cycle transiently to measure pt’s true I time and set IT accordingly • Flow Cycling can only occur if target tidal volume has been reached in PRVC and Machine Volume • Should only be used with patients that have low FiO2 requirements because by limiting IT Mean Airway Pressure may be affected
Breath Termination Hierarchy • Alarm • Supercedes all other criteria • Volume Limit • If set, supercedes all lesser criteria • Flow Cycle • *In volume targeted and controlled modes only after set volume is achieved Time / Volume Cycled If no other criteria intercede
Advanced Settings Volume Control Ventilation - VCV
VCV - Volume Control Volume Peak Flow PSV Flow Trigger
Vsync On/Off Vsync Rise Time Sigh Select Volume Parameter in VCV
Volume Parameter in VCV When Vsync is selected, Volume Limit becomes apparent and the Vsync icon appears on screen. 0=Off 1=On
Advanced SettingsVsync • Vsync operates similar to PRVC • Flow is only difference • Set in Vsync • Automatic in PRVC • The maximum step change between two consecutive breaths is 3 cm H2O.
Volume Limit • This feature allows the clinician to set a maximum volume limit that cannot be exceeded during a Vsync breath. • When the volume limit is reached, a visual display appears in the alarm area. The display remains illuminated as long as the volume limit is active
Advanced SettingsVolume Parameter in VCV • “Vsync Rise Time” • Setting range from 1 to 9, 1 being fastest and 9 slowest. • With Vsync active, this controlallows the clinician to adjust the speed at which flow is delivered to the patient. • “Sigh” • A sigh volume breath is delivered every 100th breath in place of the next normal volume breath. • The sigh volume breath is 1.5 times the set tidal volume
Advanced SettingsPeak Flow in VCV Demand Flow On/Off Waveform Type 0 = Square 1 = Ramp
Intra-Breath Demand Flow • Peak Inspiratory Pressure (Ppeak) every 2 milliseconds throughout the breath cycle • “Virtual” Pressure Support Target of the greater of: • PEEP + 2 cmH2O or • Ppeak – 2 cmH2O • Maximum PEEP x 2 • Ppeak decrease by 2 cmH2O • “switch over” to Pressure Support at virtual PSV Target. • Once Tidal volume has been delivered • “looks” at the inspiratory flow • Inspiratory Flow > set peak flow • flow cycled at 25% of peak inspiratory flow • Inspiratory Flow = set flow • ends as Volume Control breath
Intra-Breath Demand Flow in VCV Note augmented flow to meet patients inspiratory demand. Demand ends before set volume has been delivered. Demand continues through end of breath. Breath is FLOW CYCLED at 25% of PIFR.
Intra-Breath Demand Flow ON / OFF Double cycling in periods of high demand
PSV & Flow Trigger in VCV These Advanced Settings are the same for all modes and types of ventilation
Advanced Settings Pressure Regulated Volume Control - PRVC
PRVC – Pressure Regulated Volume Control Flow Trigger Inspiratory Time Volume
Volume Parameter in PRVC Similar settings to PCV since PRVC is a hybrid of PCV